Decomposition of nD-rotations: Classification, properties and algorithm

International audienceIn this paper, the decomposition of nD-rotations is studied. Using this decomposition, nD-rotations are classified and properties are underlined. A generalization of the algorithm previously presented by the authors to decompose nD-rotation into planar rotations is proposed. Since our framework includes experimental applications, we designed a method that is somewhat robust to noise. An alternate algorithm based on the Schur decomposition is investigated. A comparison between both methods is finally provided

Three distinct sarcomeric patterns of skeletal muscle revealed by SHG and TPEF microscopy.

International audienceWe have extensively characterized the sarcomeric SHG signal as a function of animal species (rat versus xenopus), age (adult versus larval) and tissue preparation (fixed or fresh) and we found that the main feature of this signal is a single peak per mature sarcomere (about 85% of all sarcomeres). The remaining (15%) was found to be either double peak per mature sarcomere or mini sarcomeres (half of a sarcomere) using alpha-actinin immuno detection of the Z-band. The mini sarcomeres are often found in region of pitchfork-like SHG pattern. We suggest that double peak SHG pattern could indicate regions of sarcomeric proteolysis whereas pitchfork-like SHG pattern could reveal sarcomeric assembly

Proteomics reveals a switch in CDK1-associated proteins upon M-phase exit during the Xenopus laevis oocyte to embryo transition.

International audienceCyclin-dependent kinase 1 (CDK1) is a major M-phase kinase which requires the binding to a regulatory protein, Cyclin B, to be active. CDK1/Cyclin B complex is called M-phase promoting factor (MPF) for its key role in controlling both meiotic and mitotic M-phase of the cell cycle. CDK1 inactivation is necessary for oocyte activation and initiation of embryo development. This complex process requires both Cyclin B polyubiquitination and proteosomal degradation via the ubiquitin-conjugation pathway, followed by the dephosphorylation of the monomeric CDK1 on Thr161. Previous proteomic analyses revealed a number of CDK1-associated proteins in human HeLa cells. It is, however, unknown whether specific partners are involved in CDK1 inactivation upon M-phase exit. To better understand CDK1 regulation during MII-arrest and oocyte activation, we immunoprecipitated (IPed) CDK1 together with its associated proteins from M-phase-arrested and M-phase-exiting Xenopus laevis oocytes. A mass spectrometry (MS) analysis revealed a number of new putative CDK1 partners. Most importantly, the composition of the CDK1-associated complex changed rapidly during M-phase exit. Additionally, an analysis of CDK1 complexes precipitated with beads covered with p9 protein, a fission yeast suc1 homologue well known for its high affinity for CDKs, was performed to identify the most abundant proteins associated with CDK1. The screen was auto-validated by identification of: (i) two forms of CDK1: Cdc2A and B, (ii) a set of Cyclins B with clearly diminishing number of peptides identified upon M-phase exit, (iii) a number of known CDK1 substrates (e.g. peroxiredoxine) and partners (e.g. HSPA8, a member of the HSP70 family) both in IP and in p9 precipitated pellets. In IP samples we also identified chaperones, which can modulate CDK1 three-dimensional structure, as well as calcineurin, a protein necessary for successful oocyte activation. These results shed a new light on CDK1 regulation via a dynamic change in the composition of the protein complex upon M-phase exit and the oocyte to embryo transition

Properties and Applications of the Simplified Generalized Perpendicular Bisector

International audienceThis paper deals with the Simplified Generalized Perpendicular Bisector (SGBP) presented in [15,1]. The SGPB has some interesting properties that we explore. We show in particular that the SGPB can be used for the recognition and exhaustive parameter estimation of noisy discrete circles. A second application we are considering is the error estimation for a class of rotation reconstruction algorithms

A phenomenological approach to investigate the pre-reflexive contents of consciousness during sound production

International audienceThis article describes a listening experiment based on elici-tation interviews that aims at describing the conscious experience of a subject submitted to a perceptual stimulation. As opposed to traditional listening experiments in which subjects are generally influenced by closed or suggestive questions and limited to predefined, forced choices, elicita-tion interviews make it possible to get deeper insight into the listener's perception, in particular to the pre-reflexive content of the conscious experiences. Inspired by previous elicitation interviews during which subjects passively listened to sounds, this experience is based on an active task during which the subjects were asked to reproduce a sound with a stylus on a graphic tablet that controlled a synthesis model. The reproduction was followed by an elicitation interview. The trace of the graphic gesture as well as the answers recorded during the interview were then analyzed. Results revealed that the subjects varied their focus towards both the evoked sound source, and intrinsic sound properties and also described their sensations induced by the experience

Diatom milking? A review and new approaches

The rise of human populations and the growth of cities contribute to the depletion of natural resources, increase their cost, and create potential climatic changes. To overcome difficulties in supplying populations and reducing the resource cost, a search for alternative pharmaceutical, nanotechnology, and energy sources has begun. Among the alternative sources, microalgae are the most promising because they use carbon dioxide (CO2) to produce biomass and/or valuable compounds. Once produced, the biomass is ordinarily harvested and processed (downstream program). Drying, grinding, and extraction steps are destructive to the microalgal biomass that then needs to be renewed. The extraction and purification processes generate organic wastes and require substantial energy inputs. Altogether, it is urgent to develop alternative downstream processes. Among the possibilities, milking invokes the concept that the extraction should not kill the algal cells. Therefore, it does not require growing the algae anew. In this review, we discuss research on milking of diatoms. The main themes are (a) development of alternative methods to extract and harvest high added value compounds; (b) design of photobioreactors; (c) biodiversity and (d) stress physiology, illustrated with original results dealing with oleaginous diatoms

Positive and Negative Urgency as a single coherent construct: Evidence from a large‐scale network analysis in clinical and non‐clinical samples

Aims: Negative and positive urgency are emotion-related impulsivity traits that are thought to be transdiagnostic factors in psychopathology. However, it has recently been claimed that these two traits are closely related to each other and that considering them separately might have limited conceptual and methodological value. The present study aimed to examine whether positive and negative urgency constructs constitute separate impulsivity traits. Methods: In contrast to previous studies that have used latent variable approaches, this study employed an item-based network analysis conducted in two different samples: a large sample of non-clinical participants (N = 18,568) and a sample of clinical participants with psychiatric disorders (N = 385). Results: The network analysis demonstrated that items denoting both positive and negative urgency cohere as a single cluster of items termed “general urgency” in both clinical and non-clinical samples, thereby suggesting that differentiating positive and negative urgency as separate constructs is not necessary. Conclusion: These findings have important implications for the conceptualization and assessment of urgency and, more broadly, for future research on impulsivity, personality, and psychopathology

Retrospective Analysis of Treatment Pathways in Patients With BRAFV600E-mutant Metastatic Colorectal Carcinoma - MORSECRC.

BACKGROUND/AIM Metastatic colorectal cancer (mCRC) is a heterogeneous disease with distinct molecular subtypes. The BRAFV600E-mutation found in approximately 8-12% of mCRC patients is associated with poor prognosis. Guideline recommendations for this population are mostly based on small cohorts due to lack of clinical data. This retrospective analysis was designed to evaluate (approved) therapeutic approaches and algorithms in BRAFV600E-mutant mCRC prior to approval of the targeted combination encorafenib plus cetuximab in Germany, Austria, and Switzerland. PATIENTS AND METHODS Anonymized data from BRAFV600E-mutant mCRC patients were analyzed retrospectively regarding 1st-, 2nd- and 3rd-line treatment using descriptive statistics. RESULTS Forty-two patients were eligible for analysis (mean age 62.1 years, 47.6% female). At initial diagnosis, 20 patients (47.6%) were documented with right-sided tumors. Most patients (81.0%) were tested for BRAF before 1st-line. Four patients (9.5%) showed high microsatellite instability (MSI-H). Based on 94 treatment lines, chemotherapy combined with targeted therapy (TT) was used mostly (61.7%), followed by chemotherapy alone (19.1%). Backbone therapies were most frequently FOLFOXIRI (27.7%), FOLFOX/CAPOX (22.3%), or FOLFIRI (20.2%). Anti-VEGF/VEGFR and anti-EGFR-treatments were used in 45.7% and 23.4% of patients, respectively. Across all treatment lines and types, the predominantly documented reason for discontinuation was lack of efficacy. CONCLUSION Combined chemotherapy+TT (anti-VEGF/VEGFR and anti-EGFR) played a predominant role in BRAFV600E-mutated mCRC treatment prior to approval of the targeted combination encorafenib plus cetuximab. Since lack of efficacy was the major reason for treatment discontinuation, newly approved therapies including encorafenib plus cetuximab and - for MSI-H tumors - pembrolizumab represent urgently needed options for future mCRC patients

Confinement of Dyes inside Boron Nitride Nanotubes: Photostable and Shifted Fluorescence down to the Near Infrared

Fluorescence is ubiquitous in life science and used in many fields of research ranging from ecology to medicine. Among the most common fluorogenic compounds, dyes are being exploited in bioimaging for their outstanding optical properties from UV down to the near IR (NIR). However, dye molecules are often toxic to living organisms and photodegradable, which limits the time window for in vivo experiments. Here, it is demonstrated that organic dye molecules are passivated and photostable when they are encapsulated inside a boron nitride nanotube (dyes@BNNT). The results show that the BNNTs drive an aggregation of the encapsulated dyes, which induces a redshifted fluorescence from visible to NIR‐II. The fluorescence remains strong and stable, exempt of bleaching and blinking, over a time scale longer than that of free dyes by more than 104. This passivation also reduces the toxicity of the dyes and induces exceptional chemical robustness, even in harsh conditions. These properties are highlighted in bioimaging where the dyes@BNNT nanohybrids are used as fluorescent nanoprobes for in vivo monitoring of Daphnia Pulex microorganisms and for diffusion tracking on human hepatoblastoma cells with two‐photon imaging

Evaluation of a congruent auditory feedback for Motor Imagery BCI

International audienceDesigning a feedback that helps participants to achieve higher performances is an important concern in brain-computer interface (BCI) research. In a pilot study, we demonstrate how a congruent auditory feedback could improve classification in a electroencephalography (EEG) motor imagery BCI. This is a promising result for creating alternate feedback modality