Eye movements in response to different cognitive activities measured by eyetracking: a prospective study on some of the neurolinguistics programming theories

The eyes are in constant movement to optimize the interpretation of the visual scene by the brain. Eye movements are controlled by complex neural networks that interact with the rest of the brain. The direction of our eye movements could thus be influenced by our cognitive activity (imagination, internal dialogue, memory, etc.). A given cognitive activity could then cause the gaze to move in a specific direction (a brief movement that would be instinctive and unconscious). Neuro Linguistic Programming (NLP), which was developed in the 1970s by Richard Bandler and John Grinder (psychologist and linguist respectively), issued a comprehensive theory associating gaze directions with specific mental tasks. According to this theory, depending on the visual path observed, one could go back to the participant's thoughts and cognitive processes. Although NLP is widely used in many disciplines (communication, psychology, psychotherapy, marketing, etc), to date, few scientific studies have examined the validity of this theory. Using eye tracking, this study explores one of the hypotheses of this theory, which is one of the pillars of NLP on visual language. We created a protocol based on a series of questions of different types (supposed to engage different brain areas) and we recorded by eye tracking the gaze movements at the end of each question while the participants were thinking and elaborating on the answer. Our results show that 1) complex questions elicit significantly more eye movements than control questions that necessitate little reflection, 2) the movements are not random but are oriented in selected directions, according to the different question types, 3) the orientations observed are not those predicted by the NLP theory. This pilot experiment paves the way for further investigations to decipher the close links between eye movements and neural network activities in the brain

Using the R Package Spatstat to Assess Inhibitory Effects of Microregional Hypoxia on the Infiltration of Cancers of the Head and Neck Region by Cytotoxic T Lymphocytes

(1) Background: The immune system has physiological antitumor activity, which is partially mediated by cytotoxic T lymphocytes (CTL). Tumor hypoxia, which is highly prevalent in cancers of the head and neck region, has been hypothesized to inhibit the infiltration of tumors by CTL. In situ data validating this concept have so far been based solely upon the visual assessment of the distribution of CTL. Here, we have established a set of spatial statistical tools to address this problem mathematically and tested their performance. (2) Patients and Methods: We have analyzed regions of interest (ROI) of 22 specimens of cancers of the head and neck region after 4-plex immunofluorescence staining and whole-slide scanning. Single cell-based segmentation was carried out in QuPath. Specimens were analyzed with the endpoints clustering and interactions between CTL, normoxic, and hypoxic tumor areas, both visually and using spatial statistical tools implemented in the R package Spatstat. (3) Results: Visual assessment suggested clustering of CTL in all instances. The visual analysis also suggested an inhibitory effect between hypoxic tumor areas and CTL in a minority of the whole-slide scans (9 of 22, 41%). Conversely, the objective mathematical analysis in Spatstat demonstrated statistically significant inhibitory interactions between hypoxia and CTL accumulation in a substantially higher number of specimens (16 of 22, 73%). It showed a similar trend in all but one of the remaining samples. (4) Conclusion: Our findings provide non-obvious but statistically rigorous evidence of inhibition of CTL infiltration into hypoxic tumor subregions of cancers of the head and neck. Importantly, these shielded sites may be the origin of tumor recurrences. We provide the methodology for the transfer of our statistical approach to similar questions. We discuss why versions of the Kcross and pcf.cross functions may be the methods of choice among the repertoire of statistical tests in Spatstat for this type of analysis

Utilisation de l'analyse automatisée de la parole et des mesures des émotions faciales sur des vidéos pour évaluer les effets des dispositifs de relaxation: une étude pilote

International audienceRapid relaxation installations in order to reduce stress appear more and more in public or work places. However, the effects of such devices on physiological and psychological parameters have not been scientifically tested yet. This pilot study (N=40) evaluates the variations of vocal speech and facial emotions parameters in 3-minute videos of participant recorded just before and after relaxation, on four different groups, three of them using a different rapid (15 minutes) sensorial immersion relaxation devices and a control group using no device. Vocal speech parameters included sound duration, pause mean duration, sound duration ratio, mean vocal frequency (F0), standard deviation of F0, minimum and maximum of F0, jitter and shimmer. Facial emotion analysis included neutral, happy, sad, surprised, angry, disgusted, scared, contempt, valence and arousal. The objective of this study is to evaluate different parameters of the automated vocal and facial emotions analysis that could be of use to evaluate the relaxation effect of different devices and to measure their variations in the different experimental groups. We identified significant parameters that can be of use for evaluating rapid relaxation devices, particularly voice prosody and minimum vocal frequency, and some facial emotion such as happy, sad, the valence and arousal. Those parameters allowed us to discriminate distinct effects of the different devices used: in G1 (control) and G2 (spatialized sounds), we observed a slowdown in voice prosody; in G3 (Be-Breathe) a decrease in minimum vocal frequency and an increase of arousal; while in G4 (3D-video) we found an increase in facial emotion valence (happy increasing and sad decreasing). Other parameters tested were not affected by relaxation.Les installations de relaxation rapide afin de réduire le stress apparaissent de plus en plus dans les lieux publics ou de travail. Cependant, les effets de ces dispositifs sur les paramètres physiologiques et psychologiques n'ont pas encore été testés scientifiquement. Cette étude pilote (N = 40) évalue les variations des paramètres de la parole vocale et des émotions faciales dans des vidéos de 3 minutes de participant enregistrées juste avant et après la relaxation, sur quatre groupes différents, trois d'entre eux utilisant une immersion sensorielle rapide (15 minutes) différente. des appareils de relaxation et un groupe témoin n'utilisant aucun appareil. Les paramètres de la parole vocale comprenaient la durée du son, la durée moyenne de la pause, le rapport de durée du son, la fréquence vocale moyenne (F0), l'écart type de F0, le minimum et le maximum de F0, la gigue et le miroitement. L'analyse des émotions faciales comprenait la neutralité, la joie, la tristesse, la surprise, la colère, le dégoût, la peur, le mépris, la valence et l'excitation. L'objectif de cette étude est d'évaluer différents paramètres de l'analyse automatisée des émotions vocales et faciales qui pourraient être utiles pour évaluer l'effet de relaxation de différents appareils et mesurer leurs variations dans les différents groupes expérimentaux. Nous avons identifié des paramètres significatifs qui peuvent être utiles pour évaluer les dispositifs de relaxation rapide, en particulier la prosodie de la voix et la fréquence vocale minimale, et certaines émotions faciales telles que le bonheur, la tristesse, la valence et l'excitation. Ces paramètres nous ont permis de discriminer des effets distincts des différents appareils utilisés: pour G1 (contrôle) et G2 (sons spatialisés), nous avons observé un ralentissement de la prosodie vocale; dans le groupe G3 (Be-Breathe) une diminution de la fréquence vocale minimale et une augmentation de l'éveil; enfin, pour G4 (vidéo 3D), nous avons trouvé une augmentation de la valence des émotions faciales (augmentation de la joie et diminution de la tristesse). Les autres paramètres testés n'ont pas été affectés par la relaxation

Almost one year of TROPOMI/S5P total ozone column data: global ground-based validation

Póster presentado en: ATMOS 2018, celebrado en Salzburgo (Austria) del 26 al 29 de noviembre de 2018.In this work we present the validation results of almost one year of TROPOMI Near Real Time (NRTI) and OFFLine (OFFL) data against ground-based quality-assured Brewer and Dobson total ozone column (TOC) measurements deposited in the World Ozone and Ultraviolet Radiation Data Center (WOUDC). Additionally, comparisons to Brewer measurements from the European Brewer Network (EUBREWNET) and the Canadian Network are performed, as well as to twilight zenith-sky measurements obtained with ZSL-DOAS (Zenith Scattered Light Differential Optical Absorption Spectroscopy) instruments, that form part of the SAOZ network (Système d'Analyse par Observation Zénitale) of the Network for the Detection of Atmospheric Composition Change (NDACC). Through the comparison of the TROPOMI measurements to the total ozone ground-based measurements from stations that are distributed globally, as the background truth, the dependence of the new instrument on latitude, cloud properties, solar zenith and viewing angles, among others, is examined. Validation results show that the mean bias and the standard deviation of the percentage difference between TROPOMI and QA ground TOC meet the product requirements

TROPOMI/S5P total ozone column data: global ground-based validation and consistency with other satellite missions

In this work, the TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are presented and compared to daily ground-based quality-assured Brewer and Dobson TOC measurements deposited in the World Ozone and Ultraviolet Radiation Data Centre (WOUDC). Additional comparisons to individual Brewer measurements from the Canadian Brewer Network and the European Brewer Network (Eubrewnet) are performed. Furthermore, twilight zenith-sky measurements obtained with ZSL-DOAS (Zenith Scattered Light Differential Optical Absorption Spectroscopy) instruments, which form part of the SAOZ network (Système d'Analyse par Observation Zénitale), are used for the validation. The quality of the TROPOMI TOC data is evaluated in terms of the influence of location, solar zenith angle, viewing angle, season, effective temperature, surface albedo and clouds. For this purpose, globally distributed ground-based measurements have been utilized as the background truth. The overall statistical analysis of the global comparison shows that the mean bias and the mean standard deviation of the percentage difference between TROPOMI and ground-based TOC is within 0 –1.5 % and 2.5 %–4.5 %, respectively. The mean bias that results from the comparisons is well within the S5P product requirements, while the mean standard deviation is very close to those limits, especially considering that the statistics shown here originate both from the satellite and the ground-based measurements.This research has been supported by the European Space Agency “Preparation and Operations of the Mission Performance Centre (MPC) for the Copernicus Sentinel-5 Precursor Satellite” (contract no. 4000117151/16/1-LG)

Global patterns in genomic diversity underpinning the evolution of insecticide resistance in the aphid crop pest Myzus persicae

Abstract: The aphid Myzus persicae is a destructive agricultural pest that displays an exceptional ability to develop resistance to both natural and synthetic insecticides. To investigate the evolution of resistance in this species we generated a chromosome-scale genome assembly and living panel of >110 fully sequenced globally sampled clonal lines. Our analyses reveal a remarkable diversity of resistance mutations segregating in global populations of M. persicae. We show that the emergence and spread of these mechanisms is influenced by host–plant associations, uncovering the widespread co‐option of a host-plant adaptation that also offers resistance against synthetic insecticides. We identify both the repeated evolution of independent resistance mutations at the same locus, and multiple instances of the evolution of novel resistance mechanisms against key insecticides. Our findings provide fundamental insights into the genomic responses of global insect populations to strong selective forces, and hold practical relevance for the control of pests and parasites.Peer reviewedFinal Published versio

Super-Resolution Dynamic Imaging of Dendritic Spines Using a Low-Affinity Photoconvertible Actin Probe

The actin cytoskeleton of dendritic spines plays a key role in morphological aspects of synaptic plasticity. The detailed analysis of the spine structure and dynamics in live neurons, however, has been hampered by the diffraction-limited resolution of conventional fluorescence microscopy. The advent of nanoscopic imaging techniques thus holds great promise for the study of these processes. We implemented a strategy for the visualization of morphological changes of dendritic spines over tens of minutes at a lateral resolution of 25 to 65 nm. We have generated a low-affinity photoconvertible probe, capable of reversibly binding to actin and thus allowing long-term photoactivated localization microscopy of the spine cytoskeleton. Using this approach, we resolve structural parameters of spines and record their long-term dynamics at a temporal resolution below one minute. Furthermore, we have determined changes in the spine morphology in response to pharmacologically induced synaptic activity and quantified the actin redistribution underlying these changes. By combining PALM imaging with quantum dot tracking, we could also simultaneously visualize the cytoskeleton and the spine membrane, allowing us to record complementary information on the morphological changes of the spines at super-resolution

Transmission Characteristics of the 2009 H1N1 Influenza Pandemic: Comparison of 8 Southern Hemisphere Countries

While in Northern hemisphere countries, the pandemic H1N1 virus (H1N1pdm) was introduced outside of the typical influenza season, Southern hemisphere countries experienced a single wave of transmission during their 2009 winter season. This provides a unique opportunity to compare the spread of a single virus in different countries and study the factors influencing its transmission. Here, we estimate and compare transmission characteristics of H1N1pdm for eight Southern hemisphere countries/states: Argentina, Australia, Bolivia, Brazil, Chile, New Zealand, South Africa and Victoria (Australia). Weekly incidence of cases and age-distribution of cumulative cases were extracted from public reports of countries' surveillance systems. Estimates of the reproduction numbers, R0, empirically derived from the country-epidemics' early exponential phase, were positively associated with the proportion of children in the populations (p = 0.004). To explore the role of demography in explaining differences in transmission intensity, we then fitted a dynamic age-structured model of influenza transmission to available incidence data for each country independently, and for all the countries simultaneously. Posterior median estimates of R0 ranged 1.2–1.8 for the country-specific fits, and 1.29–1.47 for the global fits. Corresponding estimates for overall attack-rate were in the range 20–50%. All model fits indicated a significant decrease in susceptibility to infection with age. These results confirm the transmissibility of the 2009 H1N1 pandemic virus was relatively low compared with past pandemics. The pattern of age-dependent susceptibility found confirms that older populations had substantial – though partial - pre-existing immunity, presumably due to exposure to heterologous influenza strains. Our analysis indicates that between-country-differences in transmission were at least partly due to differences in population demography

Principles of chromosomal organization: lessons from yeast

The spatial organization of genes and chromosomes plays an important role in the regulation of several DNA processes. However, the principles and forces underlying this nonrandom organization are mostly unknown. Despite its small dimension, and thanks to new imaging and biochemical techniques, studies of the budding yeast nucleus have led to significant insights into chromosome arrangement and dynamics. The dynamic organization of the yeast genome during interphase argues for both the physical properties of the chromatin fiber and specific molecular interactions as drivers of nuclear order