SUSY breaking mediation by throat fields

We investigate, in the general framework of KKLT, the mediation of supersymmetry breaking by fields propagating in the strongly warped region of the compactification manifold ('throat fields'). Such fields can couple both to the supersymmetry breaking sector at the IR end of the throat and to the visible sector at the UV end. We model the supersymmetry breaking sector by a chiral superfield which develops an F-term vacuum expectation value. It turns out that the mediation effect of vector multiplets propagating in the throat can compete with modulus-anomaly mediation. Moreover, such vector fields are naturally present as the gauge fields arising from isometries of the throat (most notably the SO(4) isometry of the Klebanov-Strassler solution). Their mediation effect is important in spite of their large 4d mass. The latter is due to the breaking of the throat isometry by the compact manifold at the UV end of the throat. The contribution from heavy chiral superfields is found to be subdominant.Comment: 15 pages; v2: typos corrected, references added; v3: comments adde

Visualization of Diffusion within Nanoarrays

The direct experimental characterization of diffusion processes at nanoscale remains a challenge that could help elucidate processes in biology, medicine and technology. In this report, two experimental approaches were employed to visualize ion diffusion profiles at the orifices of nanopores (radius (ra) of 86 ± 6 nm) in array format: (1) electrochemically assisted formation of silica deposits based on surfactant ion transfer across nanointerfaces between two immiscible electrolyte solutions (nanoITIES); (2) combined atomic force - scanning electrochemical microscopy (AFM-SECM) imaging of topography and redox species diffusion through the nanopores. The nature of the diffusion zones formed around the pores is directly related to the interpore distance within the array. Nanopore arrays with different ratios of pore center-to-center separation (rc) to pore radius (ra) were fabricated by focused ion beam (FIB) milling of silicon nitride (SiN) membranes, with 100 pores in a hexagonal arrangement. The ion diffusion profiles determined by the two visualization methods indicated the formation of overlapped or independent diffusion profiles at nanopore arrays with rc/ra ratios of 21 ± 2 and 91 ± 7, respectively. In particular, the silica deposition method resulted in formation of a single deposit encompassing the complete array with closer nanopore arrangement, whereas individual silica deposits were formed around each nanopore within the more widely spaced array. The methods reveal direct experimental evidence of diffusion zones at nanopore arrays and provide practical illustration that the pore-pore separation within such arrays has a significant impact on diffusional transport as the pore size is reduced to the nanoscale. These approaches to nanoscale diffusion zone visualization open up possibilities for better understanding of molecular transport processes within miniaturized systems

Microscopic gel – liquid interfaces supported by hollow microneedle array for voltammetric drug detection

This report describes a method for integration of a gel–liquid interface in hollow microneedles compatible with minimally invasive, electrochemical detection of drugs in vivo. The electrochemical sensor was characterised using cyclic voltammetry with tetraethyl ammonium. The experimental work demonstrated the detection of propranolol as a representative drug in physiological buffer with the microneedle system. A calibration curve for propranolol was built from measurements with differential pulse stripping voltammetry, indicating a sensitivity of 43nAμM−1, a limit of detection of 50nM and a linear range between 50 and 200nM

Multimessenger NuEM Alerts with AMON

The Astrophysical Multimessenger Observatory Network (AMON), has developed a real-time multi-messenger alert system. The system performs coincidence analyses of datasets from gamma-ray and neutrino detectors, making the Neutrino-Electromagnetic (NuEM) alert channel. For these analyses, AMON takes advantage of sub-threshold events, i.e., events that by themselves are not significant in the individual detectors. The main purpose of this channel is to search for gamma-ray counterparts of neutrino events. We will describe the different analyses that make-up this channel and present a selection of recent results

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/)

Mésostructuration d’interfaces et immobilisation de protéines et de bactéries par électrogénération sol-gel pour des applications analytiques

National audienceThe principle of sol-gel electrogeneration is described. This process has been applied to electrode surfaces and liquid-liquid interfaces mesostructuration, to the immobilization of redox proteins and bacteria.Analytical applications have been considered at these different stages of research, for the detection of heavy metals ions and biological molecules in aqueous media.Le principe de l’électrogénération sol-gel est présenté. Ce procédé a été appliqué à la mésostructuration de surfaces d’électrodes et de micro-interfaces liquide-liquide, à la modification d’électrodes nanostructurées, à l’immobilisation de protéines redox et de bactéries.Des applications analytiques ont été considérées à ces différentes étapes de développement, pour la détection d’ions de métaux lourds et de molécules biologiquesen milieu aqueux

Ion transfer at polarised liquid-liquid interfaces modified with adsorbed silica nanoparticles

International audienceThe interface between two immiscible electrolyte solutions (ITIES) can act as a scaffold for the assembly of nanometer-sized objects. Here we followed the adsorption of silica nanoparticles of 12 nm diameter at the ITIES by AC voltammetry and their interactions with methylene blue (MB +), selected as a model ion, by cyclic voltammetry and UV-vis absorption spectroscopy. We determined the association constant, í µí°¾ í µí±Ží µí±‘í µí± í µí±Ží µí±ž , of adsorption of MB + onto silica nanoparticles to be 1.66 10 5 , which indicated a strong affinity between them. This strong affinity shifted the Gibbs free energy of transfer by-8.9 kJ mol-1. This is in contrast with the other two ions investigated (Eosin B and tetraethylammonium), which demonstrated low affinity for the silica nanoparticles. By combining the ability of silica to adsorb onto the ITIES and their affinity for MB + , we were able to accumulate MB + at the ITIES.

Amperometric Sensor for Selective On-Site Analysis of Free Sulfite in Wines

International audienceAccurate and rapid on-site analysis of free SO 2 content is crucial in the process of winemaking from a producer and consumer perspective. Herein, we present an amperometric sensor based on commercially available screenprinted electrodes coupled with an electrochemical oxygen filter. The developed amperometric method gave a linear response in a concentration range up to 200 mg L −1 with a limit of quantification of 7.5 mg L −1. The applicability of the developed sensor was successfully tested on 27 white and red wine samples and compared to the Ripper method (iodometry) that is a standard procedure for free SO 2 determination. The sensor exhibits similar precision and accuracy but shows no interference from oxidizable species such as ascorbic acid, which is a major advantage over iodometric titration. The performance of the sensor was in addition positively evaluated during on-site analysis in a winery

Mesoporous silica thin films for molecular sieving and electrode surface protection against biofouling

International audienceElectrode fouling is a major challenge for the long term use of sensors in real samples as it leads to the decay of the electroanalytical signal and is often caused by the formation of an inhibiting layer formed by biomolecules. We demonstrate here that ordered and vertically aligned mesoporous silica generated at the surface of an indium tin oxide electrode by electrochemically assisted self-assembly act as a molecular sieve and a protective layer for the electrode surface. They indeed prevent the adsorption of size excluded large undesired molecules (e.g. haemoglobin) while allowing the detection of small redox active molecules likely to reach the electrode surface through the film (e.g. propranolol) with almost no loss of sensitivity. At a bare electrode, the oxidation of propranolol is completely inhibited in the presence of 5 mu M haemoglobin. At a modified electrode, the sensitivity for propranolol in the absence of haemoglobin is (72.8 +/- 2.9) mA mol(-1) (R-2= 0.992, N= 7) and it remains similar in the presence of 5 mu M haemoglobin with a value of (67.4 +/- 7.2) mA mol(-1) (R-2= 0.992, N= 7)