The relative contribution of noise and adaptation to competition during tri-stable motion perception

Animals exploit antagonistic interactions for sensory processing and these can cause oscillations between competing states. Ambiguous sensory inputs yield such perceptual multi-stability. Despite numerous empirical studies using binocular rivalry or plaid pattern motion, the driving mechanisms behind the spontaneous transitions between alternatives remain unclear. In the current work, we used a tri-stable barberpole motion stimulus combining empirical and modelling approaches to elucidate the contributions of noise and adaptation to underlying competition. We first robustly characterised the coupling between perceptual reports of transitions and continuously recorded eye direction, identifying a critical window of 480ms before button presses within which both measures were most strongly correlated. Second, we identified a novel non monotonic relationship between stimulus contrast and average perceptual switching rate with an initially rising rate before a gentle reduction at higher contrasts. A neural fields model of the underlying dynamics introduced in previous theoretical work and incorporating noise and adaptation mechanisms was adapted, extended and empirically validated. Noise and adaptation contributions were confirmed to dominate at the lower, and higher, contrasts respectively. Model simulations with two free parameters, controlling adaptation dynamics and direction thresholds, captured the measured mean transition rates for participants. We verified the shift from noise dominated towards adaptation-driven in both the eye direction distributions and inter-transition duration statistics. This work combines modelling and empirical evidence to demonstrate the signal strength dependent interplay between noise and adaptation during tri- stability. We propose that the findings generalise beyond the barberpole stimulus case to ambiguous perception in continuous feature space

Gender in the Climate-Conflict Nexus: "Forgotten" Variables, Alternative Securities, and Hidden Power Dimensions

The literature on the security implications of climate change, and in particular on potential climate-conflict linkages, is burgeoning. Up until now, gender considerations have only played a marginal role in this research area. This is despite growing awareness of intersections between protecting women’s rights, building peace and security, and addressing environmental changes. This article advances the claim that adopting a gender perspective is integral for understanding the conflict implications of climate change. We substantiate this claim via three main points. First, gender is an essential, yet insufficiently considered intervening variable between climate change and conflict. Gender roles and identities as well as gendered power structures are important in facilitating or preventing climate-related conflicts. Second, climate change does affect armed conflicts and social unrest, but a gender perspective alters and expands the notion of what conflict can look like, and whose security is at stake. Such a perspective supports research inquiries that are grounded in everyday risks and that document alternative experiences of insecurity. Third, gender-differentiated vulnerabilities to both climate change and conflict stem from inequities within local power structures and socio-cultural norms and practices, including those related to social reproductive labor. Recognition of these power dynamics is key to understanding and promoting resilience to conflict and climate change. The overall lessons drawn for these three arguments is that gender concerns need to move center stage in future research and policy on climate change and conflicts

A predictive inline model for nonlinear stimulated Raman scattering in a hohlraum plasma

In this Letter, we introduce a new inline model for stimulated Raman scattering (SRS), which runs on our radiation hydrodynamics code TROLL. The modeling follows from a simplified version of a rigorous theory for SRS, which we describe, and accounts for nonlinear kinetic effects. It also accounts for the SRS feedback on the plasma hydrodynamics. We dubbed it PIEM because it is a fully PredIctivE Model, no free parameter is to be adjusted \textit{a posteriori}~in order to match experimental results. PIEM predictions are compared against experimental measurements performed at the Ligne d'Int\'egration Laser. From these comparisons, we discuss PIEM ability to correctly catch the impact of nonlinear kinetic effects on SRS

Effect of antibiotics on mechanical properties of Bordetella pertussis examined by atomic force microscopy.

In recent years, the coevolution of microorganisms with current antibiotics has increased the mechanisms of bacterial resistance, generating a major health problem worldwide. Bordetella pertussis is a bacterium that causes whooping cough and is capable of adopting different states of virulence, i.e. virulent or avirulent states. In this study, we explored the nanomechanical properties of both virulent and avirulent B. pertussis as exposed to various antibiotics. The nanomechanical studies highlighted that only virulent B. pertussis cells undergo a decrease in their cell elastic modulus and height upon antimicrobial exposure, whereas their avirulent counterparts remain unaffected. This study also permitted to highlight different mechanical properties of individual cells as compared to those growing in close contact with other individuals. In addition, we analyzed the presence on the bacterial cell wall of Filamentous hemagglutinin adhesin (FHA), the major attachment factor produced by virulent Bordetella spp., under different virulence conditions by Force Spectroscopy

Influence of pH on the Cytotoxic Activity of Inositol Hexakisphosphate (IP6) in Prostate Cancer

Objectives: In the present study, we investigated whether the pH of IP6 could influence its anti-tumoral activity in vitro. Methods: PC-3 cells were exposed to IP6 at pH 5, pH 7, and pH 12 and we evaluated the metabolic activity (WST-1 assay), cell proliferation (cell count), cell cycle distribution (FACS), and mitochondrial depolarization (JC-1 staining) in vitro. Results: Our results demonstrated that IP6 at pH 5 and pH 12 were more potent at lowering the metabolic activity of PC-3 cells than IP6 at pH 7. Treatment with IP6 at pH 12 also caused the greatest inhibition in cellular proliferation and accumulation of PC-3 cells in sub-G1. Finally, IP6 at pH 12 lead to a reduction in phospho-AKT and phospho-PDK1 and upregulated phospho-ERK. Conclusion: Together, our data strongly suggest that the pH of IP6 effectively modulates its anti-tumoral activity and should be reported in future studies

Ebp1 expression in benign and malignant prostate

<p>Abstract</p> <p>Background</p> <p>ErbB3-binding protein 1 (Ebp1) is a member of the <it>PA2G4 </it>family of proliferation-regulated proteins that is expressed in multiple malignant and non-malignant cells. ErbB3 and other members of the EGFR family have been implicated in cancer progression, it however remains unknown whether Ebp1 participate in prostate cancer progression <it>in vivo</it>. Therefore, the present study examines Ebp1 expression in cancerous and non-cancerous prostates tissues. Ebp1 expression was also correlated to known Ebp1 regulated proteins (Androgen receptor (AR), Cyclin D1 & ErbB3) and the proliferation marker Ki67. Furthermore we evaluated whether Ebp1 expression correlated with biochemical recurrence (BCR) following radical prostatectomy.</p> <p>Methods</p> <p>The expression of Ebp1, AR, Cyclin D1, ErbB3 and Ki67 were evaluated by immunohistochemistry using three separate tissue micro-arrays containing normal prostate tissues, non-cancerous tissue adjacent to the primary tumor, hormone-sensitive and hormone-refractory cancerous tissues. Multivariate COX regression analysis was performed with four clinical parameters in order to correlate Ebp1 expression with PCa progression.</p> <p>Results</p> <p>The expression of Ebp1 significantly increased with the progression from normal to hormone sensitive and to hormone refractory PCa. Furthermore, we observed strong correlation between Ebp1 expression and the nuclear expression of AR, Cyclin D1 and ErbB3 in both normal adjacent and cancer tissues. The expression of AR, Cyclin D1 and ErbB3 in normal adjacent tissues correlated with PSA relapse, whereas Ebp1 on its own did not significantly predict PSA relapse. Finally, in a multivariate analysis with a base clinical model (Gleason, Pre-op PSA, surgical margins and P-stage) we identified the multi-marker combination of Ebp1+/Cyclin D1- as an independent predictor of PSA relapse with a hazard ratio of 4.79.</p> <p>Conclusion</p> <p>Although not related to disease recurrence, this is the first <it>in vivo </it>study to report that Ebp1 expression correlates with PCa progression.</p

SOTER on ROS: A Run-Time Assurance Framework on the Robot Operating System

We present an implementation of SOTER, a run-time assurance framework for building safe distributed mobile robotic (DMR) systems, on top of the Robot Operating System (ROS). The safety of DMR systems cannot always be guaranteed at design time, especially when complex, off-the-shelf components are used that cannot be verified easily. SOTER addresses this by providing a language-based approach for run-time assurance for DMR systems. SOTER implements the reactive robotic software using the language P, a domain-specific language designed for implementing asynchronous event-driven systems, along with an integrated run-time assurance system that allows programmers to use unfortified components but still provide safety guarantees. We describe an implementation of SOTER for ROS and demonstrate its efficacy using a multi-robot surveillance case study, with multiple run-time assurance modules. Through rigorous simulation, we show that SOTER enabled systems ensure safety, even when using unknown and untrusted components.Comment: 20th International Conference on Runtime Verificatio

What does a cell need for efficient protein secretion: Deciphering, modeling, and augmenting the CHO machinery

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ON THE INTERACTION BETWEEN SEA BREEZE AND SUMMER MISTRAL AT THE EXIT OF THE RHÔNE VALLEY DURING THE ESCOMPTE EXPERIMENT

The abstract investigates experimentally and numerically the structure of a combined Mistral sea breeze event at the exit of the Rhône valley in southeastern France, as well as the near shoreline water variability at the alternation between the Mistral and the sea breeze