Children's perception and understanding of ambiguous figures

Abstract Background Research has shown that people need to be pre-informed about the ambiguity in order to perceive both interpretations (reverse) of an ambiguous figure. Children younger than 4 years mostly do not experience reversal even when informed. This suggests that the processes involved in reversal develop at this age. Aim The aim of the studies reported here was to disentangle the cognitive processes (metarepresentation, executive function, mental imagery) and the role of eye-movements involved in reversal. Method Four studies (7 experiments), each involving around sixty 3-, 4- and 5-year-old children, using multiple tasks, were conducted. The primary tasks used were the Ambiguous Figures Production and Reversal tasks. The secondary tasks used were metacognitive, executive function and mental imagery tasks. New tasks were also implemented in order to assess reversal abilities. Results Between the ages of 3 and 4 children develop the basic conceptual understanding for reversal (Study 1), that an ambiguous figure can have two interpretations. This is associated with the understanding of false belief, synonymy and homonymy. Between the ages of 4 and 5 children develop inhibitory (Study 3) and image generation abilities (Study 4). These are key cognitive processes necessary for reversal. Contrary to previous research, when task demands were changed (Reversal Task Revised) children’s reversal is at ceiling by the age of 5 (Studies 3 and 4). Eye-tracking data suggests that appropriate eye-movements, focusing on particular parts of the ambiguous figure, are not a primary causal factor in the development of reversal abilities (Study 4). Conclusion The ability to reverse develops in two stages. During stage 1 (between 3 and 4 years) children develop the necessary conceptual understanding that an ambiguous figure can have two interpretations (top-down knowledge). During stage 2 (between 4 and 5 years) children develop the necessary cognitive processes for reversal to occur (inhibition and image generation)

Ein Molekülion-Atom-Stoß als Doppelspaltexperiment

Das im Rahmen dieser Arbeit durchgeführte Experiment hatte zum Ziel Interferenzeffekte beim dissoziativen Ladungstransfer bei Molekülion-Atomstößen zu beobachten. Interferenzeffekte in Molekül-Atomstößen wurden von McGuire hervorgesagt und berechnet [4]. Diese Arbeit betrachtet ein ähnlichen Reaktionssystem. Die von ihm vorausgesagten Effekte wurden bestätigt. Das Experiment hat es ermöglicht, Interferenzen für alle Molekülorientierungen zu betrachten, womit man leicht Analogien zu zwei speziellen Fällen herstellen kann: mit der Molekülachse senkrecht zur Strahlrichtung entsteht eine Situation ähnlich einem Doppelspalt, bei dem die Kerne des Moleküls als Reaktionszentrum an Stelle der Spalte treten; mit der Molekülachse in Strahlrichtung entsteht eine Situation bei der Streuung an einem einzelnen Atom. In allem Molekülorientierungen erkennt man ein ringförmiges Minimum bei 1.6 a.u., wie es insbesondere bei der Beugung einem einzelnen Atom zu beobachten ist. Bei senkrechter Stellung der Molekülachse zur z-Achse überlagert durch die Streifen eines Doppelspaltes. Es war außerdem möglich den Endzustand der Teilchen zu bestimmen, so daß man sagen konnte, ob eine Teilchen angeregt aus der Reaktion hervorgegangen ist oder ob es über metastabile Zwischenzustände zerfallen ist. So ließ sich für den Impulsübertrag von 1.6 au eine Besonderheit feststellen: ein Minimum läßt sich nur im direkten Kanal ohne Anregung beobachten. Findet der Zerfall hingegen über metastabile Zwischenzustände ohne Anregung statt, so weist dieser Kanal bei etwa 1.6 au ein Maximum auf. Parallel zur Durchführung dieser Arbeit wurden erste Tests mit einem digitalen Oszillographen von Aquiris gemacht. Dieser speichert den Spannungsverlauf der Spannung an den Delaylineanoden. Peaks müssen dann schnell genug erkannt und ausgewertet werden. In der Offlineanalyse wären dann eng nebeneinander oder übereinanderliegende Peaks besser als solche zu erkennen. Diese würde die Totzeitproblematik, die sie durch die Dissoziation eines Moleküls senkrecht zur z-Achse entsteht, erheblich entschärfen

Diagnostic challenges in a child with early onset desmoplastic medulloblastoma and homozygous variants in MSH2 and MSH6

International audienceConstitutional mismatch repair deficiency (CMMRD) is an autosomal recessively inherited childhood cancer susceptibility syndrome caused by biallelic germline mutations in one of the mismatch repair (MMR

Constitutional mismatch repair deficiency–associated brain tumors: report from the European C4CMMRD consortium

Abstract Background Malignant brain tumors (BT) are among the cancers most frequently associated with constitutional mismatch repair deficiency (CMMRD), a rare childhood cancer predisposition syndrome resulting from biallelic germline mutations in mismatch repair genes. This study analyzed data from the European "Care for CMMRD" (C4CMMRD) database to describe their clinical characteristics, treatments, and outcome with the aim of improving its diagnosis/treatment. Methods Retrospective analysis of data on patients with CMMRD and malignant BT from the C4CMMRD database up to July 2017. Results Among the 87 registered patients, 49 developed 56 malignant BTs: 50 high-grade gliomas (HGG) (with giant multinucleated cells in 16/21 histologically reviewed tumors) and 6 embryonal tumors. The median age at first BT was 9.2 years [1.1–40.6], with nine patients older than 18. Twenty-seven patients developed multiple malignancies (including16 before the BT). Most patients received standard treatment, and eight patients immunotherapy for relapsed HGG. The 3- and 5-year overall survival (OS) rates were 30% (95% CI: 19–45) and 22% (95% CI: 12–37) after the first BT, with worse prognosis for HGG (3-year OS = 20.5%). Six patients were alive (median follow-up 2.5 years) and 43 dead (38 deaths, 88%, were BT-related). Other CMMRD-specific features were café-au-lait macules (40/41), multiple BTs (5/15), developmental brain anomalies (11/15), and consanguinity (20/38 families). Conclusions Several characteristics could help suspecting CMMRD in pediatric malignant BTs: giant cells on histology, previous malignancies, parental consanguinity, café-au-lait macules, multiple BTs, and developmental brain anomalies. The prognosis of CMMRD-associated BT treated with standard therapies is poor requiring new therapeutic up-front approaches

Biological Contamination Prevention for Outer Solar System Moons of Astrobiological Interest: What Do We Need to Know?

To ensure that scientific investments in space exploration are not compromised by terrestrial contamination of celestial bodies, special care needs to be taken to preserve planetary conditions for future astrobiological exploration. Significant effort has been made and is being taken to address planetary protection in the context of inner Solar System exploration. In particular for missions to Mars, detailed internationally accepted guidelines have been established. For missions to the icy moons in the outer Solar System, Europa and Enceladus, the planetary protection requirements are so far based on a probabilistic approach and a conservative estimate of poorly known parameters. One objective of the European Commission-funded project, Planetary Protection of Outer Solar System, was to assess the existing planetary protection approach, to identify inherent knowledge gaps, and to recommend scientific investigations necessary to update the requirements for missions to the icy moons

The Future of Heliophysics Research through Targeted use of Constellations

This white paper seeks to outline the benefits and challenges of constellations, ranging from the Heliophysics System Observatory, to constellations consisting of a small number of spacecraft, to large-number constellations. In moving toward this constellation era, investments are required by our sponsors to best enable our continued scientific advancement in Solar and Space Physics

The Lunar Lander Neutron and Dosimetry (LND) Experiment on Chang'E 4

Chang'E 4 is the first mission to the far side of the Moon and consists of a lander, a rover, and a relay spacecraft. Lander and rover were launched at 18:23 UTC on December 7, 2018 and landed in the von K\'arm\'an crater at 02:26 UTC on January 3, 2019. Here we describe the Lunar Lander Neutron \& Dosimetry experiment (LND) which is part of the Chang'E 4 Lander scientific payload. Its chief scientific goal is to obtain first active dosimetric measurements on the surface of the Moon. LND also provides observations of fast neutrons which are a result of the interaction of high-energy particle radiation with the lunar regolith and of their thermalized counterpart, thermal neutrons, which are a sensitive indicator of subsurface water content.Comment: 38 pages, submitted to Space Science Review

High prevalence of BRCA1 stop mutation c.4183C>T in the Tyrolean population: implications for genetic testing

Screening for founder mutations in BRCA1 and BRCA2 has been discussed as a cost-effective testing strategy in certain populations. In this study, comprehensive BRCA1 and BRCA2 testing was performed in a routine diagnostic setting. The prevalence of the BRCA1 stop mutation c.4183C>T, p.(Gln1395Ter), was determined in unselected breast and ovarian cancer patients from different regions in the Tyrol. Cancer registry data were used to evaluate the impact of this mutation on regional cancer incidence. The mutation c.4183C>T was detected in 30.4% of hereditary BRCA1-associated breast and ovarian cancer patients in our cohort. It was also identified in 4.1% of unselected (26% of unselected triple negative) Tyrolean breast cancer patients and 6.8% of unselected ovarian cancer patients from the Lower Inn Valley (LIV) region. Cancer incidences showed a region-specific increase in age-stratified breast and ovarian cancer risk with standardized incidence ratios of 1.23 and 2.13, respectively. We, thus, report a Tyrolean BRCA1 founder mutation that correlates to a local increase in the breast and ovarian cancer risks. On the basis of its high prevalence, we suggest that targeted genetic analysis should be offered to all women with breast or ovarian cancer and ancestry from the LIV region