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International audience; The increase in anaerobic digestion systems has profoundly affected the waste management of territories, particularly for agricultural systems. Changes in cultural practices and imports of organic waste modify the carbon (C) and nitrogen (N) fluxes on territories where anaerobic digestion is implemented. Successful anaerobic digestion can increase the economic and ecological efficiency of the waste management system. Conversely, poor anaerobic digestion leads to low economic and environmental efficiency due to greenhouse gas emissions and nutrient loss. Modeling the impact of anaerobic digestion on the systems integrating anaerobic digestion can improve the efficiency of these practices. The aim of this study was to develop, analyze, and evaluate a simple mass balance tool able to predict carbon and nitrogen fluxes in anaerobic digestion systems. The tool is composed of an exhaustive substrate database used by three models: (i) an anaerobic digestion model that predicts C and N contents in biogas and digestate; (ii) a phase separation model that predicts C and N content in liquid and solid phase digestates; and (iii) a storage model that predicts C and N content in raw, liquid phase, and solid phase digestates, as well as C and N emissions during storage. Sensitivity analyses were performed on the tool to determine critical inputs. Sensitivity analysis showed that outputs were highly sensitive to their respective inputs and to total inputs of solids. Performance evaluation showed that the tool can provide good quality predictions with R-2 correlations between observation and prediction varying from 0.72 to 0.99 with the best predictions obtained for raw digestate.

Sustainable water oxidation requires low-cost, stable, and efficient redox couples, photosensitizers, and catalysts. Here, we introduce the in situ self-assembly of metal-atom-free organic-based semiconductive structures on the surface of carbon supports. The resulting TTF/TTF•+@carbon junction (TTF = tetrathiafulvalene) acts as an all-in-one highly stable redox-shuttle/photosensitizer/molecular-catalyst triad for the visible-light-driven water oxidation reaction (WOR) at neutral pH, eliminating the need for metallic or organometallic catalysts and sacrificial electron acceptors. A water/butyronitrile emulsion was used to physically separate the photoproducts of the WOR, H+ and TTF, allowing the extraction and subsequent reduction of protons in water, and the in situ electrochemical oxidation of TTF to TTF•+ on carbon in butyronitrile by constant anode potential electrolysis. During 100 h, no decomposition of TTF was observed and O2 was generated from the emulsion while H2 was constantly produced in the aqueous phase. This work opens new perspectives for a new generation of metal-atom-free, low-cost, redox-driven water-splitting strategies.

D.M. and H.D. thank the Israel Science Foundation (Contract No. 641/18) and the National Natural Science Foundation of China (Grant No. 21904143) for financial support. P.P. and S.M. are grateful for the financial support from the Swiss National Science Foundation under Grant Ambizione Energy 160553. P.P. also gratefully acknowledges the Academy Research Fellow funding (Grant No. 315739) and project funding (Grant No. 334828) from the Academy of Finland. E.S. is grateful to the Development Program of Lomonosov Moscow State University and the Russian Science Foundation (Grant No. 19-13-00283). H.H.G. acknowledges the Swiss National Science Foundation grants: 200021_175745 “Photo Induced Charge Transfer Reaction at Molecular Interfaces: towards new routes of solar energy storage” and 20SC-1_193608 “Photoproduction of hydrogen in biphasic systems with electron donor recycling (PHOTO2H)”. Emulsification of immiscible two-phase fluids, i.e., one condensed phase dispersed homogeneously as tiny droplets in an outer continuous medium, plays a key role in medicine, food, chemical separations, cosmetics, fabrication of micro- and nanoparticles and capsules, and dynamic optics. Herein, we demonstrate that water clusters/droplets can be formed in an organic phase via the spontaneous assembling of ionic bilayers. We term these clusters ionosomes, by analogy with liposomes where water clusters are encapsulated in a bilayer of lipid molecules. The driving force for the generation of ionosomes is a unique asymmetrical electrostatic attraction at the water/oil interface: small and more mobile hydrated ions reside in the inner aqueous side, which correlate tightly with the lipophilic bulky counterions in the adjacent outer oil side. These ionosomes can be formed through electrochemical (using an external power source) or chemical (by salt distribution) polarization at the liquid–liquid interface. The chargedensity of the cations, the organic solvent, and the synergistic effects between tetraethylammonium and lithium cations, all affecting the formation of ionosomes, were investigated. These results clearly prove that a new emulsification strategy is developed providing an alternative and generic platform, besides the canonical emulsification procedure with either ionic or nonionic surfactants as emulsifiers. Finally, we also demonstrate the detection of individual ionosomes via single-entity electrochemistry.

The specific concentrations of florfenicol and thiamphenicol in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield, were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. The FARSC for florfenicol was estimated. However, due to the lack of data, the calculation of the FARSC for thiamphenicol was not possible until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels in feed that showed to have an effect on growth promotion/increased yield were reported for florfenicol, whilst for thiamphenicol no suitable data for the assessment were available. Uncertainties and data gaps associated to the levels reported were addressed. For florfenicol, it was recommended to perform further studies to supply more diverse and complete data related to the requirements for calculation of the FARSC, whereas for thiamphenicol, the recommendation was to generate the data required to fill the gaps which prevented the FARSC calculation. info:eu-repo/semantics/publishedVersion

The specific concentrations of tilmicosin, tylosin and tylvalosin in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield, were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC, it was not possible to conclude the assessment until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels in feed that showed to have an effect on growth promotion/increased yield were reported for tilmicosin and tylosin, whilst for tylvalosin no suitable data for the assessment were available. It was recommended to carry out studies to generate the data that are required to fill the gaps which prevented the calculation of the FARSC for these three antimicrobials. info:eu-repo/semantics/publishedVersion

The specific concentrations of tiamulin and valnemulin in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC, it was not possible to conclude the assessment until further experimental data become available. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels in feed that showed to have an effect on growth promotion/increased yield were reported for tiamulin, while for valnemulin no suitable data for the assessment were available. It was recommended to carry out studies to generate the data that are required to fill the gaps which prevented the calculation of the FARSC for these two antimicrobials. info:eu-repo/semantics/publishedVersion

International audience; Bacterial genomes, organized intracellularly as nucleoids, are composed of a main chromosome coexisting with different types of secondary replicons. Secondary replicons are major drivers of 16 bacterial adaptation by gene exchange. They are highly diverse in type and size, ranging from less than 2 to more than 1000 kb, and must integrate with bacterial physiology, including to the nucleoid dynamics, to limit detrimental costs leading to their counter-selection. We show that large DNA circles, whether from a natural plasmid or excised from the chromosome tend to localize in a dynamic manner in a zone separating the nucleoid from the cytoplasm at the edge of the nucleoid.This localization is in good agreement with in silico simulations of DNA circles in the nucleoid volume. Subcellular positioning systems counteract this tendency, allowing replicons to enter the nucleoid space. In enterobacteria, these systems are found in replicons above 25 kb, defining the limit with small randomly segregated plasmids. Larger replicons carry at least one of the three described family of systems, ParAB, ParRM and StbA. Replicons above 180 kb all carry a ParAB system, suggesting this system is specifically required in the cases of large replicons. Simulations demonstrated that replicon size profoundly affects localization, compaction and dynamics of DNA circles in the nucleoid volume. The present work suggests that presence of partition systems on the larger plasmids or chromids is not only due to selection for accurate segregation but also to counteract their unmixing with the chromosome and consequent exclusion from the nucleoid.

In this work, a simple procedure for the preparation of an inkjet printed disposable graphene electrode is reported. Commercial graphene ink was printed on a kapton substrate and the resulting electrode was 30 min treated by oxygen plasma, then modified by a bismuth salt. The as prepared electrode was characterized by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), laser scanning microscopy (LSM) and scanning electron microscopy (SEM) coupled to energy-dispersive X-ray spectroscopy (EDX). The sensing properties of the characterized electrodes were then investigated using cyclic voltammetry and Electrochemical Impedance Spectroscopy (EIS). After-wards, these electrodes were exploited in a comparative way for the electroa-nalysis of Cadmium(II) and Lead(II) ions. An increase in the electrode sensi-tivity due to its modification and to the presence of bismuth was observed. Some preliminary experiments based on stripping square wave voltammetry highlighted the interest of using the proposed disposable inkjet printed elec-trodes for the electrochemical detection of heavy metals in tap water.

Foreign Body Reaction (FBR) is a critical issue to be addressed when polyethylene terephthalate (PET) textile implants are considered in the medical field to treat pathologies involving hernia repair, revascularization strategies in arterial disease, and aneurysm or heart valve replacement. The natural porosity of textile materials tends to induce exaggerated tissue ingrowth which may prevent the implants from remaining flexible. The purpose of this study is to assess the influence of the textile topography of various woven substrates on the wetting properties of these substrates and on their in vitro interaction with mesenchymal stem cells (MSC) at 24 and 72 hr. The tests were performed both at yarn and fabric level under forced wetting and ingrowth conditions in order to replicate the mechanisms going on in vivo under blood pressure. Results demonstrate that cell proliferation is influenced by the textile wetting properties, which can be tuned at yarn and fabric level. In particular, it is shown that a satin weave obtained from porous spun yarn limits cell proliferation due to the high porosity of the yarn and the limited saturation index of the weave. Yarn and fabric saturation seems to play a predominant role in cell proliferation on textile substrates.

International audience; T cell exclusion causes resistance to cancer immunotherapies via immune checkpoint blockade (ICB). Myeloid cells contribute to resistance by expressing signal regulatory protein-α (SIRPα), an inhibitory membrane receptor that interacts with ubiquitous receptor CD47 to control macrophage phagocytosis in the tumor microenvironment. Although CD47/SIRPα-targeting drugs have been assessed in preclinical models, the therapeutic benefit of selectively blocking SIRPα, and not SIRPγ/CD47, in humans remains unknown. We report a potent synergy between selective SIRPα blockade and ICB in increasing memory T cell responses and reverting exclusion in syngeneic and orthotopic tumor models. Selective SIRPα blockade stimulated tumor nest T cell recruitment by restoring murine and human macrophage chemokine secretion and increased anti-tumor T cell responses by promoting tumor-antigen crosspresentation by dendritic cells. However, nonselective SIRPα/SIRPγ blockade targeting CD47 impaired human T cell activation, proliferation, and endothelial transmigration. Selective SIRPα inhibition opens an attractive avenue to overcoming ICB resistance in patients with elevated myeloid cell infiltration in solid tumors.

The mechanism by which interfaces in solution can be polarised depends on the nature of the charge carriers. In the case of a conductor, the charge carriers are electrons and the polarisation is homogeneous in the plane of the electrode. In the case of an insulator covered by ionic moieties, the polarisation is inhomogeneous and discrete in the plane of the interface. Despite these fundamental differences, these systems are usually treated in the same theoretical framework that relies on the Poisson–Boltzmann equation for the solution side. In this perspective, we show that interfaces polarised by discrete charge distributions are rather ubiquitous and that their associated potential drop significantly differs from those of conductor–electrolyte interfaces. We show that these configurations, spanning liquid–liquid interfaces, charged silica–water interfaces, metal oxide interfaces, supercapacitors, ion-exchange membranes and even biological membranes can be uniformly treated under a common “Discrete Helmholtz” model where the discrete charges are compensated by a single layer of correlated counter-ions, thereby generating a sharp potential drop at the interface., Electrolytes in solution are strongly correlated with discrete charges at insulating interfaces inducing a behavior significantly different from that of conducting interfaces.

The Mn-III/Mn-II redox couple with a standard potential of +1.51 V versus the standard hydrogen electrode (SHE) has attracted interest for the design of V/Mn redox flow batteries (RFBs). However, Mn-III disproportionation leads to a loss of capacity, an increase in pressure drop, and electrode passivation caused by the formation of MnO2 particles during battery cycling. In this work, the influence of Ti-IV or/and V-V on Mn-III stability in acidic conditions is studied by formulating four different electrolytes in equimolar ratios (Mn, Mn/Ti, Mn/V, Mn/V/Ti). Voltammetry studies have revealed an ECi process for Mn-II oxidation responsible for the electrode passivation. SEM and XPS analysis demonstrate that the nature and morphology of the passivating oxides layer depend strongly on the electrolyte composition. Spectroelectrochemistry highlights the stabilization effect of Ti-IV and V-V on Mn-III. At a comparable pH, the amount of Mn-III loss through disproportionation is decreased by a factor of 2.5 in the presence of Ti-IV or/and V-V. Therefore, V-V is an efficient substitute for Ti-IV to stabilize the Mn-III electrolyte for RFB applications.

Prussian blue (PB) and Prussian blue analogues (PBAs) are commonly synthesized by conventional methods, such as chemical precipitation, thermal decomposition, and electrochemical deposition. Herein...

International audience; DARPP-32 (dopamine-and cAMP-regulated phosphoprotein with an apparent Mr of 32 000), now also known as phosphoprotein phosphatase 1 regulatory subunit 1B (PPP1R1B), is a potent inhibitor of PP1 (also known as PPP1) when phosphorylated at Thr34 by cAMP-dependent protein kinase (PKA). DARPP-32 exhibits a remarkable regional distribution in brain, roughly similar to that of dopamine innervation. Its discovery was a culmination of the long-standing effort of Paul Greengard to understand the mechanisms through which neurotransmitters such as dopamine exert their effects on target neurons. DARPP-32 is particularly enriched in striatal projection neurons where it is regulated by numerous signals through which it integrates and amplifies responses to many stimuli. Molecular studies of DARPP-32 have revealed that its regulation and function are more complex than anticipated. It is phosphorylated on multiple sites by different protein kinases that modulate DARPP-32 properties. Primarily, when phosphorylated at Thr34 DARPP-32 is a potent inhibitor of PP1, whereas when phosphorylated at Thr75 by Cdk5 it inhibits PKA. Phosphorylation at serine residues by CK1 and CK2 modulates its intracellular localization and its sensitivity to kinases or phosphatases. Modeling studies provide evidence that the signaling pathways including DARPP-32 are endowed of strong robustness and bistable properties favoring switch-like responses. Thus DARPP-32 combined with a set of other distinct signaling molecules enriched in striatal projection neurons plays a key role in the characteristic properties and physiological function of these neurons.

Background In intensive care units (ICUs), patients experiencing post-extubation respiratory failure have poor outcomes. The use of noninvasive ventilation (NIV) to treat post-extubation respiratory failure may increase the risk of death. This study aims at comparing mortality between patients treated with NIV alternating with high-flow nasal oxygen or high-flow nasal oxygen alone. Methods Post-hoc analysis of a multicenter, randomized, controlled trial focusing on patients who experienced post-extubation respiratory failure within the 7 days following extubation. Patients were classified in the NIV group or the high-flow nasal oxygen group according to oxygenation strategy used after the onset of post-extubation respiratory failure. Patients reintubated within the first hour after extubation and those promptly reintubated without prior treatment were excluded. The primary outcome was mortality at day 28 after the onset of post-extubation respiratory failure. Results Among 651 extubated patients, 158 (25%) experienced respiratory failure and 146 were included in the analysis. Mortality at day 28 was 18% (15/84) using NIV alternating with high-flow nasal oxygen and 29% (18/62) with high flow nasal oxygen alone (difference, − 11% [95% CI, − 25 to 2]; p = 0.12). Among the 46 patients with hypercapnia at the onset of respiratory failure, mortality at day 28 was 3% (1/33) with NIV and 31% (4/13) with high-flow nasal oxygen alone (difference, − 28% [95% CI, − 54 to − 6]; p = 0.006). The proportion of patients reintubated 48 h after the onset of post-extubation respiratory failure was 44% (37/84) with NIV and 52% (32/62) with high-flow nasal oxygen alone (p = 0.21). Conclusions In patients with post-extubation respiratory failure, NIV alternating with high-flow nasal oxygen might not increase the risk of death. Trial registration number The trial was registered at http://www.clinicaltrials.gov with the registration number NCT03121482 the 20th April 2017.

Investigating and understanding dynamic biofilm growth mechanisms is challenging, often because state-of-the-art optical characterization tools provide limited information. Micrometric electrochemical imaging of Escherichia coli biofilms using Soft-Probe-Scanning Electrochemical Microscopy (Soft-Probe-SECM) is herein presented as a complementary technique. A soft microelectrode is scanned over biofilms in a gentle contact mode, which is essential to provide a constant working distance. The on-film reduction of an electro-active compound, here the oxidized form of ferrocene methanol, is used to create in situ biofilm metabolic activity maps by applying the feedback mode of SECM. SECM approach curves of identically grown biofilms suggest that the SECM-based detection of metabolic activity is surface-confined. The analysis could therefore be carried out on entire biofilms as well as on tape-stripped biofilm surface layers. The method is further capable of distinguishing between biofilms containing E. coli cells either with or without ampicillin-resistance. Finally, the SECM detection of the degradation of an E. coli biofilm in the presence of different gentamicin concentrations is presented.

The specific concentrations of amprolium in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties, are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. However, due to the lack of data on the parameters required to calculate the FARSC for amprolium, it was not possible to conclude the assessment. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels of amprolium in feed that showed to have an effect on growth promotion/increased yield were reported. The lack of antibacterial activity at clinically relevant concentrations for amprolium suggests that further studies relating to bacterial resistance are not a priority. info:eu-repo/semantics/publishedVersion

The accurate and reproducible large-scale production of catalyst layers containing low-cost, abundant electrocatalysts gains in importance. Herein, pivotal factors are discussed that need to be considered when a combined inkjet printing and photonic curing platform is used as a promising fabrication method for catalyst layers based on a model low-cost catalyst, i.e., nitrogen-doped reduced graphene oxide supported cobalt oxide nano sheets (Co3O4/N-rGO), specifically prepared to formulate an inkjet ink. The ink is stable for weeks and can reproducibly be printed with piezoelectric printheads. Ink composition and printing parameters are optimized to achieve high-resolution printing and good adhesion on glassy carbon substrates. Polyvinylpyrrolidone and ethyl cellulose are used as catalyst stabilizers in the ink and must be removed through thermal post-processing to avoid a decrease of the electrical conductivity of the catalyst layer and a degradation of the catalytic activity of the Co3O4 nanocrystals. Conventional slow oven curing (i.e., hours) and photonic curing with a Xe flash lamp (seconds) are compared to generate temperatures above 400 °C under ambient conditions. Both techniques can increase the size of the Co3O4 nanocrystals from ∼7 nm up to ∼15 nm. Photonic curing with pulses above 2 J·cm–2 shot energy density initiates the reduction of the oxidation states of cobalt from (II,III) to (II). Residues and side products of polymeric stabilizers can be found using photonic curing pulses below 10 J·cm–2. This work highlights the advances made in digital printing and post-processing for catalyst layer production and demonstrates the importance of proper design of the ink, the printing and the post-processing for the large-scale production of catalyst layers for the ORR based on low-cost materials. The findings can be transferred to other metal and mixed metal oxide nanocatalysts.

BackgroundDespite the PD-(L)1 therapy success, a majority of patients remain resistant. PD-1+IL7R+ progenitors CD8 TILs is a key T-cell subset associated with durable PD-(L)1 therapy response. However, this subset may rapidly undergo apoptosis and/or being fully exhausted after PD-(L)1 blockade. Some cytokines have the potential to strengthen PD-(L)1 therapy by promoting T cell survival, however, their clinical developments are limited by a shortened half-life and systemic toxicity. To redirect immunotherapy to tumor-specific T cells, expressing PD1, we propose to selectively deliver the pro-survival IL-7 to PD-1+ T cells using a bifunctional anti-PD1/IL-7 mutein antibody. We previously described that the anti-PD1/IL-7v abrogated suppressive activity of human Treg. Here we evaluated its preclinical anti-tumor efficacy and how it promotes the response of PD1+IL7R+ tumor-specific T cells.MethodsProliferation, IFN-γ, IL-7R signaling, and NFAT assays were tested to determine the mechanism of this antibody. For the suppressive assay, CD4 Treg and autologous CD8 Teff were co-cultured. In vivo experiments were performed in hPD-1 KI immunocompetent or humanized immunodeficient mice.ResultsThe anti-PD1/IL-7v antibody design has been optimized with a monovalent approach to enhance its biological activity: (1) preserved PD-1 antagonist activity, (2) improved pSTAT5 IL7R signaling, and (3) enhanced in vivo drug exposure and antitumor efficacy. An IL7 mutein has been designed to improve activity on PD1+ T cells while sparing PD1neg T cells.Using a chronic antigen stimulation model, anti-PD1/IL-7v restores the proliferation & survival of both early and fully exhausted CD8+ or CD4+ T cells. Similarly, anti-PD1/IL-7v, but not anti-PD1 alone, reactivates exhausted TILs isolated from human resected tumors. Gene expression analysis by Nanostring showed increase cytotoxicity, antigen presentation, and chemokines signatures. In vivo, anti-PD1/IL-7v demonstrated high monotherapy efficacy (90%) in a PD-1 sensitive orthotopic immunocompetent mouse tumor model as well as in a PD-1 refractory tumor model with 70% of CR vs 15% for anti-PD-1 alone. A selective higher expansion of stem-like/progenitors CD8 TILs was observed after therapy with anti-PD1/IL-7v compared to anti-PD1. Memory immune response was demonstrated in 100% of cured mice after tumor rechallenge in the absence of new treatment in 3 different tumor models. Finally, using two different humanized mouse models implanted with human tumors (A549 or MDA-MB231), we confirmed significant preclinical monotherapy efficacy of the anti-PD-1/IL7v.ConclusionsThese data highlight the potential of anti-PD1/IL-7 bifunctional drug to overcome immunotherapy resistance and to promote durable anti-tumor efficacy by preferentially reinvigorating PD-1+IL7R+ stem-like progenitors CD8 T cells.

Severity of hypoxaemia can be assessed using the partial pressure of arterial oxygen to fraction of inspired oxygen ratio (FiO2). However, in patients breathing through non-rebreather reservoir bag oxygen mask, accuracy of bedside FiO2 estimation methods remains to be tested. In a post-hoc analysis of a multicentre clinical trial, three FiO2 estimation methods were compared with FiO2 measured with a portable oxygen analyser introduced in the oxygen mask. Among 262 patients analysed, mean (SD) measured FiO2 was 65% (13). The 3%-formula (21% + oxygen flow rate in L/min × 3) was the most accurate method to estimate FiO2. Other methods overestimated FiO2 and hypoxaemia severity, so they should be avoided.

The synthesis of noble metal nanoparticles (i.e., silver and gold) for electrochemical applications has been widely studied using mainly wet synthesis chemical methods or electrochemical deposition methods. In this work, we propose a single-step flash photochemical method for synthesizing noble metal nanoparticles (i.e., silver, gold, and Au:Ag) in solution for electrochemical applications. The method is based on the intense pulsed radiation emitted from a xenon flashlamp, which induce the reduction of metal cations in solution to form metallic nanoparticles. The present method is based on the selective light absorption of the metal precursor salts combined with the decomposition of polyvinylpyrrolidone added to the solution. This approach can be termed as flash light synthesis.

Unfractionated heparin (UFH) is the main anticoagulante used in intensive care unit. The anticoagulant effect is monitored by activated partial thrombin time (aPTT) and anti-Xa activity (anti-Xa) measurement. However, delayed centrifugation induces platelet factor 4 (PF4) release and anti-Xa decrease. Several studies have concluded that aPTT and anti-Xa measurement should be performed within 2 hours in citrated anticoagulant but may be delayed longer in citrate theophylline adenosine and dypiridamol (CTAD) anticoagulant. The objective of this study was to compare the stability of both aPTT and anti-Xa in citrate and CTAD samples, and to determine the effect of delayed centrifugation on both aPTT, anti-Xa results, and PF4 release in citrate samples only. Methods aPTT and anti-Xa were measured in citrate and CTAD anticoagulant samples from 93 patients. Delayed centrifugation was performed in citrate samples from 31 additional patients, with hourly aPTT and anti-Xa measurement from 1 to 6 hours. In 14 of these last patients, PF4 release was also evaluated with Human CXCL4/PF4 Quantikine ELISA Kit. Results We observed a significant correlation between citrate and CTAD anticoagulant for aPTT (r2=0.94) and anti-Xa (r2=0.95). With Bland-Altman correlation, a minor bias was observed for anti-Xa (-0.025±0.041). Delayed centrifugation in citrated anticoagulant showed an excellent concordance from 1 to 4 hours for aPTT (-4.0±5.3 s) and anti-Xa (1.10-9±0.058 UI/mL) measurements. Moreover, PF4 release was not different between 1 hour (31.5±14.7 ng/mL) and 4 hours (33.8±11.8 ng/mL). Conclusion We have demonstrated that anti-Xa measurement for unfractionated heparin should be done 4 hours in citrated plasma and that CTAD was not better than citrate. However, these initial findings require confirmation using other aPTT and calibrated anti-Xa assays.

Low-grade heat (below 200 °C) is available in vast quantities from industry, or from standard roof-top solar thermal collectors. However, the production of electric power from these heat sources is challenging with existing technologies. Thermally regenerative batteries allow both the conversion and the storage of thermal energy into electric power, but they suffer from low operation voltages and low output power. Here, we propose a thermally regenerative nanoslurry flow battery based on copper complexation with acetonitrile in non-aqueous solutions operating at voltages above 1 V. The Cu(i) complex can be destabilized by the removal of acetonitrile by distillation, leading to the production of solid copper nanoparticles and Cu(ii) in solution, thereby charging the battery. We demonstrate the electricity production at average power densities of 90 W m-2 and peak-power densities up to 150 W m-2, and estimate the theoretical efficiency of the full system at 2%. The results demonstrate a proof-of-concept for harvesting and storage of electricity from low-quality heat.

The search for highly active earth-abundant elements and nonexpensive catalysts for hydrogen evolution reaction is a vital and demanding task to minimize energy consumption. Transition metals incorporated into molybdenum sulfides are promising candidates for hydrogen evolution because of their unique chemical and physical properties. Here, we first describe a general strategy for the synthesis of particle-shaped molybdenum-based ternary refractory metal sulfides (MMoSx; M = Fe, Co, Ni, and Mn) through a simple hot-injection method. The newly developed materials are affirmed as valuable alternatives to noble-metal platinum because of their simple fabrication, inexpensiveness, and impressive catalytic performance. We present highly efficient catalysts for hydrogen evolution at a polarized water/1,2-dichloroethane interface by using decamethylferrocene (DMFc). The kinetics of hydrogen evolution studies are monitored by two-phase reactions using UV-vis spectroscopy and also further proven by gas chromotography. These ternary refractory metal sulfide catalysts show high catalytic activities upon hydrogen evolution comparable to platinum. The rate of hydrogen evolution for the MMoSx catalysts changed in the order Ni > Co > Fe > Mn according to the types of first-row transition metals.

Summary Matrix-assisted laser desorption ionization time-of-flight mass spectrometry is used to detect intact whole exosomes, yielding exosomal fingerprints within minutes. This rapid exosome detection approach is proposed as a potential tool for cancer studies. Melanoma, a dangerous form of skin cancer, is investigated as a cancer model. The approach allows classification of melanoma cell lines from the stage level through mathematical analysis of the fingerprints and enables the tracking of protein transfer from parental cells to the secreted exosomes by following up certain fingerprint peaks. Protein identities of exosomal fingerprint peaks were clarified by correlation with top-down and bottom-up proteomics. The protein-assigned fingerprints provide a qualitative and semi-quantitative detection of melanoma biomarkers and help to explore melanoma progression via exosome-mediated intercellular communication. Targeting bloodstream-circulating exosomes, the proposed exosome fingerprinting approach also promises fast detection of melanoma diseases and dynamic monitoring of the disease state with proof of concept in mouse and human.

International audience; In this paper, nitrogen transformations were studied on 13 substrates from agro-industrial, agricultural or urban sources using a new method. This method was developed to determine the kinetics and balance of nitrogen transformation during anaerobic digestion with high inoculum-to-substrate ratio while avoiding instabilities with nutrients addition. Inoculum was washed to reduce ammonium content and carbonates were added to adjust buffer capacity. Results show that kinetics of nitrogen mineralisation depends mainly on initial substrate. Nitrogen was quickly transformed before stabilisation (from 2 to 8 days). Four types of nitrogen transformation were identified: (a) rapid mineralisation (transformation of organic nitrogen (Norg) into ammonium) for blood, (b) moderate mineralisation, for sludge, green waste and food waste, (c) limited protein hydrolysis (no transformation of nitrogen forms) for slurry and manure and, (d) immobilisation of nitrogen (transformation of ammonium into Norg (biomass growth)) for fruits, straw and greases. Biological nitrogen potential (BNP) ranged from ' 7.1 to 22.8 gN kgWW'1 and showed a good correlation (R2 = 0.80) with Norg from substrates. On co-digestion tests, no significant inhibitions of mineralisation nor synergies between substrates were assessed allowing to calculate BNP value of the mix as the weighting average of the BNP values of each added substrate. Examples of calculation of nitrogen form on digestate show that do not use BNP may induce to under or overestimations of the final NH4 + content. A comparison of this methodology with an already published methodology shows an excellent correlation but a systematic difference of 7.2 gN kgWW'1, which seems to be explained by a better capacity of the methodology developed in this study to describe immobilisation phenomena. © 2019, Springer Nature B.V.

Patients with Crohn’s disease exhibit abnormal colonization of the intestine by adherent invasive E. coli (AIEC). They adhere to epithelial cells, colonize them and survive inside macrophages. It appeared recently that AIEC LF82 adaptation to phagolysosomal stress involves a long lag phase in which many LF82 cells become antibiotic tolerant. Later during infection, they proliferate in vacuoles and form colonies harboring dozens of LF82 bacteria. In the present work, we investigated the mechanism sustaining this phase of growth. We found that intracellular LF82 produced an extrabacterial matrix that acts as a biofilm and controls the formation of LF82 intracellular bacterial communities (IBCs) for several days post infection. We revealed the crucial role played by the pathogenicity island encoding the yersiniabactin iron capture system to form IBCs and for optimal LF82 survival. These results illustrate that AIECs use original strategies to establish their replicative niche within macrophages., Prudent et al. show that intracellular bacteria related to the Crohn’s disease, LF82, produce an extra-bacterial matrix that acts as a biofilm and controls the formation of LF82 intracellular bacterial communities. This study provides insights into the strategies that adherent invasive E. coli use to establish their replicative niche within macrophages.

H2 O2 is a versatile chemical and can be generated by the oxygen reduction reaction (ORR) in proton donor solution in molecular solvents or room temperature ionic liquids (IL). We investigated this reaction at interfaces formed by eleven hydrophobic ILs and acidic aqueous solution as a proton source with decamethylferrocene (DMFc) as an electron donor. H2 O2 is generated in colorimetrically detectable amounts in biphasic systems formed by alkyl imidazolium hexafluorophosphate or tetraalkylammonium bis(trifluoromethylsulfonyl)imide ionic liquids. H2 O2 fluxes were estimated close to liquid|liquid interface by scanning electrochemical microscopy (SECM). Contrary to the interfaces formed by hydrophobic electrolyte solution in a molecular solvent, H2 O2 generation is followed by cation expulsion to the aqueous phase. Weak correlation between the H2 O2 flux and the difference between DMFc/DMFc+ redox potential and 2 electron ORR standard potential indicates kinetic control of the reaction.

The computational codes used in the evaluation of the ESFR-SMART reactor performance and specifically their sodium boiling models are assessed using two KNS-37 LOF experiments, i.e. L22 and L29 tests, where boiling onset and two-phase flow regime up to dry-out occurred. The well-equipped KNS-37 experimental facility provided very valuable information for understanding the physical phenomena occurring in a 37-pin subassembly under LOF conditions, as well as experimental data to be used for computational tools validation. NATOF-2D, SAS-SFR, TRACE, ASTEC-Na, CATHARE-2 & CATHARE-3 and NEPTUNE_CFD codes have been used in this exercise in order to compare the various boiling models and conclude on the advantages and limitations of them based on the comparison against the experimental data. Beyond boiling onset, the various sodium two-phase flow approaches determine the ability of the code to correctly represent the rewetting and voiding phases as well as cladding dry-out onset. A simulation performed by a CFD approach (NEPTUNE_CFD code) considering liquid-vapor interfaces by an interface-tracking method is also shown and compared with the others approaches. Conclusions on each code performance are presented where the improvements needed to solve the issues encountered are included. This paper provides a first step in the process to investigate the required evaluation of the sodium two-phase flow models able to assess the safety of new SFR core designs (e.g. low void cores) under accidental conditions such as ULOF transients.

Background and Objectives: Red blood cells (RBCs) suffer from lesions during cold storage, depending in part on their ability to counterbalance oxidative stress by activating their antioxidant defence. The aim of this study was to monitor the antioxidant power (AOP) in erythrocyte concentrates (ECs) during cold storage. Materials and Methods: Six ECs were prepared in saline-adenine-glucose-mannitol (SAGM) additive solution and followed during 43 days. The AOP was quantified electrochemically using disposable electrode strips and compared with results obtained from a colorimetric assay. Haematological data, data on haemolysis and the extracellular concentration of uric acid were also recorded. Additionally, a kinetic model was developed to extract quantitative kinetic data on the AOP behaviour. Results: The AOP of total ECs and their extracellular samples attained a maximum after 1 week of storage prior to decaying and reaching a plateau, as shown by the electrochemical measurements. The observed trend was confirmed with a colorimetric assay. Uric acid had a major contribution to the extracellular AOP. Interestingly, the AOP and uric acid levels were linked to the sex of the donors. Conclusion: The marked increase in AOP during the first week of storage suggests that RBCs are impacted early by the modification of their environment. The AOP behaviour reflects the changes in metabolism activity following the adjustment of the extracellular uric acid level. Knowing the origin, interdonor variability and the effects of the AOP on the RBCs could be beneficial for the storage quality, which will have to be further studied.

This work describes a new sensitive sensor for the simultaneous electrochemical determination by square wave anodic stripping voltammetry of Cd2+ and Pb2+ ions in aqueous solution, based on a disposable ink-jet-printed graphene electrode (IPGE) modified by a thin film of montmorillonite (Mont) clay mineral. The clay was characterized by X-ray diffraction and scanning electron microscopy while the Mont–IPGE was analyzed by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry before its exploitation for sensing studies. EIS results revealed a low electron transfer rate on Mont–IPGE during the electro-oxidation of [Fe(CN)6]3−. The stripping response on both Cd2+ and Pb2+ analytes was improved by the in situ co-deposition with bismuth, added to the electrolyte solution, on the clay substrate. The proposed electrode showed great stability and good reproducibility. The key experimental parameters governing the stripping analysis of Cd2+ and Pb2+ were optimized. A linear relationship between peak currents and concentrations of the analytes was obtained in the range from 0.01 to 0.21 µM, leading to detection limits of 0.42 nM for Cd2+and 1.14 nM for Pb2+ ions, respectively (S/N = 3). The sensitivities to Cd2+ and Pb2+ ions were 921.8 A cm−2 M−1 and 1960.8 A cm−2 M−1, respectively. The Mont–IPGE sensor was used for the quantification of lead and cadmium in a mineral water.

A noninvasive electrochemical melanoma detection approach based on using adhesive tapes for collecting and fixing cells from a suspicious skin area and transferring the cells into a scanning electrochemical microscope (SECM) is presented. The adhesive layer collects the cells reproducibly and keeps them well adhered on the tape during experiments in an electrolyte solution. A melanoma biomarker, here the intracellular enzyme tyrosinase (TYR), was imaged on the tape-collected cells without further cell lysing using antibodies that were labeled with horseradish peroxidase (HRP). The HRP labels catalyzed the oxidation of a dissolved redox-active species, which was detected at a soft microelectrode, gently brushed in contact mode over the tape. The melanoma biomarker was first detected on tape-stripped samples with murine melanoma cells of different concentrations. Thereafter, increasing levels of TYR were recorded in cells that were collected from the skin of melanoma mouse models representing three different stages of tumor growth. Additionally, SECM results of tape-stripped different human melanoma cell lines were confirmed by previous studies based on traditionally fixed and permeabilized cells.

The barrier performance and structural lightening of organic materials are increasingly desired and constitute a major challenge for manufacturers, particularly for transport and packaging. A promising technique which tends to emerge in recent years is that of multinanolayer coextrusion. The advantage is that it can produce multilayers made of thousands of very thin layers, leading to new properties due to crystalline morphology changes induced by confinement. This paper is focusing on the study of multinanolayered films with alternated polyethylene (PE), compatibilizer (PEgMA) and polyamide 6 (PA6) layers and made by a forced assembly coextrusion process equipped with layer multiplying elements (LME). PE/PA6 multilayer films consisting of 5 to 2049 layers (respectively 0 to 9 LME) were successfully obtained with well-organized multilayered structure. The evolution of the morphology and the microstructure of these two semi-crystalline polymers, when the thickness of each polymer layer decreases from micro-scale to nano-scale, was correlated to the water and gas transport properties of the PE/PA multilayers. The expected improvement of barrier properties was limited due to the on-edge orientation of crystals in very thin PE and PA6 layers. Despite this change of crystalline morphology, a slight improvement of the gas barrier properties was shown by comparing experimental results with permeabilities predicted on the basis of a serial model developed by considering a PE/PA6 interphase. This interphase observed by TEM images and the on-edge crystal orientation in multilayers were evidenced from mechanical properties showing an increase of the stiffness and the strength.

International audience; Poly(ether ketone ketone) (PEKK) is a semicrystalline polymer investigated for highly demanding applications in aerospace, transportation, electronics, and oil & gas industries. The properties required for these applications, such as thermomechanical and chemical stability, are intimately linked to the crystalline state of the material. PEKK exhibits a polymorphism that depends, among other factors, on its thermal history. The control and quantification of the crystalline state of PEKK is the subject of this study. Amorphous PEKK (T/I = 60/40, where T stands for terephthalic and I for isophthalic units) films were cold-crystallized at various crystallization temperatures, T-C, from 180 to 280 degrees C in a ventilated oven. Based on a quantitative analysis of small-angle X-ray scattering (SAXS), wide-angle X-ray scattering (WAXS), and differential scanning calorimetry (DSC) data, we propose for the first time a methodology to obtain detailed information about the crystalline state of PEKK: total crystallinity, relative amount and stability of crystalline forms, form I and form II, and melting enthalpy of 100% crystallized PEKK. The evolutions of each crystalline form and the total crystallinity with T-C were deduced. The amount of each crystalline form, form I and form II, can be tuned by controlling the heating rate to 280 degrees C. The evolution of the crystalline lamellar thickness and periodicity as well as the crystalline amount and cell parameters with T-C were interpreted and discussed in relation to the published results on PEEK, PEKK (100% T), and PEKK (100% I). Finally, the melting enthalpy of a 100% crystallized PEKK copolymer (T/I = 60/40), Delta H-m(100%) = (202 +/- 20) J/g, was estimated.