Transient Electric Field Shaping With the Linear Combination of Configuration Field Method for Enhanced Spatial Control of Microwave Plasmas

The demonstration of enhanced spatial control of nanosecond microwave plasmas generated by the time reversal plasma source is presented in this paper. This new microwave plasma source relies on the spatio-temporal control of the electric field inside an all-metal plasma reactor by modifying the waveform of a high power microwave signal. More specifically, it originally used the spatio-temporal focusing capabilities of the time reversal method to focus a high electric field in a small location. However, a parasitic microwave breakdown can still occur at sharp corners or wedges inside the cavity due to the local enhancement of the residual electric field during time reversal focusing. Thus, it is proposed to use the linear combination of configuration field method to improve field control inside the reactor. Its transient electric field shaping capabilities turn out to be a good candidate for the development of a low pressure microwave ``plasma brush''

Thiolutin is a zinc chelator that inhibits the Rpn11 and other JAMM metalloproteases

Thiolutin is a disulfide-containing antibiotic and anti-angiogenic compound produced by Streptomyces. Its biological targets are not known. We show that reduced thiolutin is a zinc chelator that inhibits the JAB1/MPN/Mov34 (JAMM) domain–containing metalloprotease Rpn11, a deubiquitinating enzyme of the 19S proteasome. Thiolutin also inhibits the JAMM metalloproteases Csn5, the deneddylase of the COP9 signalosome; AMSH, which regulates ubiquitin-dependent sorting of cell-surface receptors; and BRCC36, a K63-specific deubiquitinase of the BRCC36-containing isopeptidase complex and the BRCA1–BRCA2-containing complex. We provide evidence that other dithiolopyrrolones also function as inhibitors of JAMM metalloproteases

C5b9 Deposition in Glomerular Capillaries Is Associated With Poor Kidney Allograft Survival in Antibody-Mediated Rejection

C4d deposition in peritubular capillaries (PTC) reflects complement activation in antibody-mediated rejection (ABMR) of kidney allograft. However, its association with allograft survival is controversial. We hypothesized that capillary deposition of C5b9—indicative of complement-mediated injury—is a severity marker of ABMR. This pilot study aimed to determine the frequency, location and prognostic impact of these deposits in ABMR. We retrospectively selected patients diagnosed with ABMR in two French transplantation centers from January 2005 to December 2014 and performed C4d and C5b9 staining by immunohistochemistry. Fifty-four patients were included. Median follow-up was 52.5 (34.25–73.5) months. Thirteen patients (24%) had C5b9 deposits along glomerular capillaries (GC). Among these, seven (54%) had a global and diffuse staining pattern. Twelve of the C5b9+ patients also had deposition of C4d in GC and PTC. C4d deposits along GC and PTC were not associated with death-censored allograft survival (p = 0.42 and 0.69, respectively). However, death-censored allograft survival was significantly lower in patients with global and diffuse deposition of C5b9 in GC than those with a segmental pattern or no deposition (median survival after ABMR diagnosis, 6 months, 40.5 months and 44 months, respectively; p = 0.015). Double contour of glomerular basement membrane was diagnosed earlier after transplantation in C5b9+ ABMR than in C5b9– ABMR (median time after transplantation, 28 vs. 85 months; p = 0.058). In conclusion, we identified a new pattern of C5b9+ ABMR, associated with early onset of glomerular basement membrane duplication and poor allograft survival. Complement inhibitors might be a therapeutic option for this subgroup of patients

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Formation de la croûte et histoire thermique Martienne

Seismology has recently provided important information about the structure of the interior of Mars, and in particular its crust. The average thickness of the crust is constrained to between 50 and 67 km, with a difference of 12 to 34 km between the northern and southern hemispheres. This dichotomy is an essential feature of the Martian surface. In this thesis, I propose a new mechanism to explain its formation, based on a positive feedback process between the thickness of the crust and its extraction. As the crust is enriched in heat-producing elements, when it is thicker, the base of the lithosphere, which is a rheological and therefore thermal limit, is reached at a shallower depth. Under a thinned lithosphere, the fraction of liquid in the mantle is higher, because it is at the same temperature but at lower pressure. Magma extraction rates are therefore higher and the crust grows faster where it is thicker. Since heat diffusion in the lithosphere favours long wavelengths, we propose that this mechanism could have generated the Martian dichotomy. To test this, I have developed an asymmetric parametric thermal evolution model that includes the extraction of the crust. With this model, we demonstrate that a crustal dichotomy develops and grows from an initial negligible hemispherical perturbation. For a certain range of parameters, our model is able to reproduce observations of crustal thickness and mantle thermal structure. We also show that a stagnant layer planet with a strong crust thickness dichotomy cools slightly faster than a planet with a constant crust thickness. Finally, we show that our dichotomy growth model also provides an explanation for the formation of differentiated rocks in the Southern Highlands.La sismologie a récemment apporté d’importantes informations sur la structure de l’intérieur de Mars et en particulier de sa croûte. L’épaisseur moyenne de la croûte est contrainte entre 50 et 67 km avec une différence de 12 à 34 km entre les hémisphères Nord et Sud. Cette dichotomie est une caractéristique essentielle de la surface Martienne. Dans cette thèse, je propose un nouveau mécanisme pour expliquer sa formation, basé sur un processus de rétroaction positive entre l’épaisseur de la croûte et son extraction. La croûte étant enrichie en éléments producteurs de chaleur, lorsqu’elle est plus épaisse, la base de la lithosphère, qui est une limite rhéologique et donc thermique, est atteinte à une profondeur moindre. Sous une lithosphère amincie, la fraction de liquide dans le manteau est plus élevée, car à une même température mais à plus faible pression. Les vitesses d’extraction de magma sont alors plus élevées et la croûte croit plus rapidement là où elle est plus épaisse. La diffusion de la chaleur dans la lithosphère favorisant les grandes longueurs d’onde, nous proposons que ce mécanisme ait pu générer la dichotomie martienne. Pour le tester, j’ai développé un modèle d’évolution thermique paramétré asymétrique incluant l’extraction de la croûte. Avec ce modèle, nous démontrons qu’une dichotomie crustale se développe et croit à partir d’une perturbation, hémisphérique initiale négligeable. Pour une certaine gamme de paramètres, notre modèle est capable de reproduire les observations sur l’épaisseur de la croûte et la structure thermique du manteau. Nous montrons aussi qu’une planète en couche stagnante avec une forte dichotomie d’épaisseur de croûte se refroidit légèrement plus vite qu’une planète dont la croûte est d’épaisseur constante. Enfin, nous démontrons que notre modèle de croissance de la dichotomie fournit également une explication pour la formation de roches différenciées dans les Hautes Plateaux du Sud

Formation de la croûte et histoire thermique Martienne

La sismologie a récemment apporté d’importantes informations sur la structure de l’intérieur de Mars et en particulier de sa croûte. L’épaisseur moyenne de la croûte est contrainte entre 50 et 67 km avec une différence de 12 à 34 km entre les hémisphères Nord et Sud. Cette dichotomie est une caractéristique essentielle de la surface Martienne. Dans cette thèse, je propose un nouveau mécanisme pour expliquer sa formation, basé sur un processus de rétroaction positive entre l’épaisseur de la croûte et son extraction. La croûte étant enrichie en éléments producteurs de chaleur, lorsqu’elle est plus épaisse, la base de la lithosphère, qui est une limite rhéologique et donc thermique, est atteinte à une profondeur moindre. Sous une lithosphère amincie, la fraction de liquide dans le manteau est plus élevée, car à une même température mais à plus faible pression. Les vitesses d’extraction de magma sont alors plus élevées et la croûte croit plus rapidement là où elle est plus épaisse. La diffusion de la chaleur dans la lithosphère favorisant les grandes longueurs d’onde, nous proposons que ce mécanisme ait pu générer la dichotomie martienne. Pour le tester, j’ai développé un modèle d’évolution thermique paramétré asymétrique incluant l’extraction de la croûte. Avec ce modèle, nous démontrons qu’une dichotomie crustale se développe et croit à partir d’une perturbation, hémisphérique initiale négligeable. Pour une certaine gamme de paramètres, notre modèle est capable de reproduire les observations sur l’épaisseur de la croûte et la structure thermique du manteau. Nous montrons aussi qu’une planète en couche stagnante avec une forte dichotomie d’épaisseur de croûte se refroidit légèrement plus vite qu’une planète dont la croûte est d’épaisseur constante. Enfin, nous démontrons que notre modèle de croissance de la dichotomie fournit également une explication pour la formation de roches différenciées dans les Hautes Plateaux du Sud.Seismology has recently provided important information about the structure of the interior of Mars, and in particular its crust. The average thickness of the crust is constrained to between 50 and 67 km, with a difference of 12 to 34 km between the northern and southern hemispheres. This dichotomy is an essential feature of the Martian surface. In this thesis, I propose a new mechanism to explain its formation, based on a positive feedback process between the thickness of the crust and its extraction. As the crust is enriched in heat-producing elements, when it is thicker, the base of the lithosphere, which is a rheological and therefore thermal limit, is reached at a shallower depth. Under a thinned lithosphere, the fraction of liquid in the mantle is higher, because it is at the same temperature but at lower pressure. Magma extraction rates are therefore higher and the crust grows faster where it is thicker. Since heat diffusion in the lithosphere favours long wavelengths, we propose that this mechanism could have generated the Martian dichotomy. To test this, I have developed an asymmetric parametric thermal evolution model that includes the extraction of the crust. With this model, we demonstrate that a crustal dichotomy develops and grows from an initial negligible hemispherical perturbation. For a certain range of parameters, our model is able to reproduce observations of crustal thickness and mantle thermal structure. We also show that a stagnant layer planet with a strong crust thickness dichotomy cools slightly faster than a planet with a constant crust thickness. Finally, we show that our dichotomy growth model also provides an explanation for the formation of differentiated rocks in the Southern Highlands

A Positive Feedback Between Crustal Thickness and Melt Extraction for the Origin of the Martian Dichotomy

International audienceA North/South difference in crustal thickness is likely at the origin of the Martian dichotomy in topography. Recent crustal thickness maps were obtained by inversion of topography and gravity data seismically anchored at the InSight station. On average, the Martian crust is 51–71 km thick with a southern crust thicker by 18–28 km than the northern one. The origin of this crustal dichotomy is still debated although the hypothesis of a large impact is at present very popular. Here, we propose a new mechanism for the formation of this dichotomy that involves a positive feedback between crustal growth and mantle melting. As the crust is enriched in heat-producing elements, the lid of a one-plate planet is hotter and thinner where the crust is thicker, inducing a larger amount of partial melt below the lid and hence a larger rate of melt extraction and crustal growth. We first demonstrate analytically that larger wavelength perturbations, that is, hemispherical perturbations, grow faster because smaller wavelengths are more attenuated by thermal diffusion. We then use a parameterized thermal evolution model with a well-mixed mantle topped by two different lids characterized by their thermal structures and thicknesses to study the growth of the crust in the two hemispheres. Our results demonstrate that this positive feedback can generate a significant crustal dichotom

TouchRAM: A Multitouch-Enabled Tool for Aspect-Oriented Software Design

This paper presents TouchRAM, a multitouch-enabled tool for agile software design modeling aimed at developing scalable and reusable software design models. The tool gives the designer access to a vast library of reusable design models encoding essential recurring design concerns. It exploits model interfaces and aspect-oriented model weaving techniques as defined by the Reusable Aspect Models (RAM) approach to enable the designer to rapidly apply reusable design concerns within the design model of the software under development. The paper highlights the user interface features of the tool specifically designed for ease of use, reuse and agility (multiple ways of input, tool-assisted reuse, multitouch), gives an overview of the library of reusable design models available to the user, and points out how the current state-of-the-art in model weaving had to be extended to support seamless model reuse.Ye

Griottes: a generalist tool for network generation from segmented tissue images

International audienceBackgroundMicroscopy techniques and image segmentation algorithms have improved dramatically this decade, leading to an ever increasing amount of biological images and a greater reliance on imaging to investigate biological questions. This has created a need for methods to extract the relevant information on the behaviors of cells and their interactions, while reducing the amount of computing power required to organize this information.ResultsThis task can be performed by using a network representation in which the cells and their properties are encoded in the nodes, while the neighborhood interactions are encoded by the links. Here, we introduce Griottes, an open-source tool to build the “network twin” of 2D and 3D tissues from segmented microscopy images. We show how the library can provide a wide range of biologically relevant metrics on individual cells and their neighborhoods, with the objective of providing multi-scale biological insights. The library’s capacities are demonstrated on different image and data types.ConclusionsThis library is provided as an open-source tool that can be integrated into common image analysis workflows to increase their capacities