44 research outputs found
Dynamic Microscopy Study of Ultrafast Charge Transfer in a Hybrid P3HT/Hyperbranched CdSe Nanoparticle Blend for Photovoltaics
No full textWe present a spectroscopic investigation on a new hyperbranched cadmium selenide nanocrystals (CdSe NC)/poly(3-hexylthiophene) (P3HT) blend, a potentially good active component in hybrid photovoltaics. Combined ultrafast transient absorption spectroscopy and morphological investigations by means of an ultrafast confocal microscope reveal a strong influence of the complex local structure on the photogenerated carrier dynamics. In particular, we map the electron-transfer process across the hybrid NC/polymer interface, and we reveal that charge separation occurs through a preferential pathway from the CdSe nanobranches to the P3HT chains. Efficient charge generation at the distributed heterojunction is also confirmed by scanning kelvin probe force microscopy measurements
Understanding natural scenes: Contributions of image statistics
No full textVisual processing of natural scenes is carried out in a hierarchical sequence of stages that involve the analysis of progressively more complex features of the visual input. Recent studies have suggested that the semantic content of natural stimuli (e.g., real world photos) can be categorized based on statistical regularities in their appearance, which can be detected early in the visual processing stream. Here we review the studies which have investigated the role of scene statistics in the perception of natural scenes, focusing on both basic visual processing and specific tasks (visual search, expert categorization, emotional picture viewing). Visual processing seems to be adapted to visual regularities in the visual input, such as the amplitude-frequency relationship. Moreover, scene statistics can aid performance in specific tasks such as distinguishing animals from artifactual scenes, possibly by modulating early visual processing stages
Creativity in NT1 patients: clinical aspects and mental state in the prediction of creative success
No full textObjectives/Introduction: Narcolepsy type 1 (NT1) is a chronic neu-
rological disorder characterised by excessive daytime sleepiness
(EDS), with rapid access into rapid eye movement (REM) sleep at
sleep onset. Clinical phenomena related to state of wakefulness and
REM sleep dissociation, including cataplexy, sleep paralysis, hypna-
gogic/hypnopompic hallucinations, REM sleep behaviour disorder
and lucid dreaming complete the clinical picture.
Given the relationship highlighted by several studies between sleep
and creative thinking and considering the features of abnormal
REM sleep phases in narcolepsy, with privileged access to sleep and
dream, a recent study hypothesized and reported higher creative po-
tential in narcoleptic patients compared to a control group.
With this study we aimed at investigating if creativity in narcolepsy
could be associated with certain symptoms and with mental dimen-
sions (such as mind wandering and daydreaming) that could predict
creative behaviour.
Methods: Sixty-six NT1 patients (mean age 38.62 ± 17.05, 31 fe-
males), took part in this study. Several measures of creativity have
been performed: creativity achievement, explored in different life
domains by a self-reported questionnaire; creative beliefs, assessed
with a scale measuring the creative self; creative performance, eval-
uated through a test assessing divergent thinking skills (generation
of alternative original solutions to an open problem).
Results: In a mediation analysis we found that sleep paralysis and
hypnagogic hallucinations indirectly influence, through creative
identity, both creative achievement (ß = 0.091, SE = 0.054, 95%
CI = 0.005, 0.211) and creative performance (ß = 0.140, SE = 0.060,
95% CI = 0.034, 0.269). In a moderation analysis mind wandering
spontaneous (R 2 = 0.169, F(3,61) = 4.15, p = 0.009) influences crea-
tive achievement through a moderation effect of sleep paralysis
and hypnagogic hallucinations. The same moderation effect was
found with mind wandering deliberate (R 2 = 0.133, F(3,61) = 3.116,
p = 0.032).
Conclusions: In conclusion, our results highlight the role of sleep pa-
ralysis and hypnagogic hallucinations in defining both creative suc-
cess and creative performance of narcoleptic patients influencing
their creative identity. Probably hypnagogic hallucinations trigger
the process of mind wandering that leads to greater creative success.
Disclosure: Anita D ́Anselmo: no conflict of interest Sergio Agnoli:
no conflict of interest Fabio Pizza: no conflict of interest Marco
Filardi: no conflict of interest Serena Mastria: no conflict of interest
Giovanni Emanuele Corazza: no conflict of interest Giuseppe Plazzi:
advisory board for UCB Pharma, Bioprojet, Idorsi
Individual differences and creative ideation: neuromodulatory signatures of mindset and response inhibition
No full textThis study addresses the modulatory role of individual mindset in explaining the relationship between response inhibition (RI) and divergent thinking (DT) using transcranial direct current stimulation (tDCS). Forty undergraduate students (22 male and 18 female), aged between 18 and 23 years (average age = 19 years, SD = 1.48), were recruited. Participants received either anodal tDCS of the right IFG coupled with cathodal tDCS of the left IFG (R + L-; N = 19) or the opposite coupling (R-L+; N = 21). We tested DT performance using the alternative uses task (AUT), measuring participants' fluency, originality, and flexibility in the response production, as well as participants' mindsets. Furthermore, we applied a go-no-go task to examine the role of RI before and after stimulating the inferior frontal gyrus (IFG) using tDCS. The results showed that the mindset levels acted as moderators on stimulation conditions and enhanced RI on AUT fluency and flexibility but not originality. Intriguingly, growth mindsets have opposite moderating effects on the change in DT, resulting from the tDCS stimulation of the left and the right IFG, with reduced fluency but enhanced flexibility. Our findings imply that understanding neural modulatory signatures of ideational processes with tDCS strongly benefits from evaluating cognitive status and control functions
Elucidating the Effect of Lead Iodide Complexation Degree behind Morphology and Performance of Perovskite Solar Cells
No full textThe inclusion of iodide additives in hybrid perovskite precursor solutions has been successfully exploited to improve the solar cell efficiency but their impact on perovskite formation, morphology and photovoltaic performance is still not clear. Here an extensive analysis of the effect of iodide additives in the solution-phase and during the perovskite film formation, as well as their effect on device performance is provided. The results demonstrate that in the solution-phase the additives promote the formation of lead poly-iodide species resulting in the disaggregation of the inorganic lead iodide framework and in the formation of smaller nuclei inducing the growth of uniform and smooth perovskite films. Most importantly, the complexation capability of different iodide additives does not only directly affect film morphology but also influences the density of defect states by varying the stoichiometry of precursors. These findings demonstrate that the fine control of the interactions of the chemical species in the solution-phase is essential for the precise control of the morphology at the nanoscale and the growth of the perovskite films with a reduced density of defect states. Therefore, the in-depth understanding of all the processes involved in the solution-phase is the first step for the development of a facile and reproducible approach for the fabrication of hybrid perovskite solar cells with enhanced photovoltaic performance
SUTURA MONOFILAMENTO DI POLIBUTESTERE PER IL CONFEZIONAMENTO DI FISTOLE ARTEROVENOSE PER EMODIALISI CON UTILIZZAZIONE DEL FATTORE DI CRESCITA
No full textIndividual differences and creative ideation: neuromodulatory signatures of mindset and response inhibition
No full textThis study addresses the modulatory role of individual mindset in explaining the relationship between response inhibition (RI) and divergent thinking (DT) using transcranial direct current stimulation (tDCS). Forty undergraduate students (22 male and 18 female), aged between 18 and 23 years (average age = 19 years, SD = 1.48), were recruited. Participants received either anodal tDCS of the right IFG coupled with cathodal tDCS of the left IFG (R + L−; N = 19) or the opposite coupling (R−L+; N = 21). We tested DT performance using the alternative uses task (AUT), measuring participants’ fluency, originality, and flexibility in the response production, as well as participants’ mindsets. Furthermore, we applied a go-no-go task to examine the role of RI before and after stimulating the inferior frontal gyrus (IFG) using tDCS. The results showed that the mindset levels acted as moderators on stimulation conditions and enhanced RI on AUT fluency and flexibility but not originality. Intriguingly, growth mindsets have opposite moderating effects on the change in DT, resulting from the tDCS stimulation of the left and the right IFG, with reduced fluency but enhanced flexibility. Our findings imply that understanding neural modulatory signatures of ideational processes with tDCS strongly benefits from evaluating cognitive status and control functions
CdSe/CdS Semiconductor Quantum Rods as Robust Fluorescent Probes for Paraffin-Embedded Tissue Imaging
No full text
