Synthèse de molécules technomimétiques pour des applications en nanomécanique

Deux machines moléculaires technomimétiques, dont la forme et la fonction miment des objets macroscopiques, ont été développées au cours de cette thèse : un moteur moléculaire et un nanovéhicule. La première de ces machines est destinée à générer un mouvement de rotation azimutal. C'est une famille de complexes de ruthénium coordinés par un ligand de type scorpionate jouant le rôle de stator et par un ligand pentaphénylcyclopentadiényl jouant le rôle de rotor. Afin de favoriser un mouvement de rotation unidirectionnel du rotor, l'introduction de chiralité a été effectuée dans la structure de la molécule. De plus, un stator fonctionnalisé par un groupement azobenzène et son complexe de ruthénium modèle ont été synthétisés afin d'arrêter de manière contrôlée la rotation du rotor. La seconde machine est quant à elle destinée à générer un mouvement de rotation altitudinal. Pour cela, une nouvelle génération de roues a été élaborée à partir de fragments subphthalocyanine dont la forme de bol ne présente pas d'interactions trop importantes avec la surface. Dès lors, la synthèse d'un nanovéhicule a été envisagée autour d'un plateau polyaromatique.Two technomimetic molecular machines, which have the shape and the function of macroscopic objects, were developed during this thesis: a molecular motor and a nanovehicle. The first one was designed in order to control an azimutal rotational motion. This machine is based on a family of ruthenium complexes coordinated by a scorpionate ligand acting as a stator and a pentaphenylcyclopentadienyl ligand acting as a rotor. In order to favor a unidirectional rotation of the rotor, introduction of chirality was achieved in the design of the molecule. Besides, a stator functionalized with an azobenzene functional group and its ruthenium model complex were synthesized in order to lock the rotation of the rotor in a controlled manner. The second machine was designed to control an altitudinal rotational motion. To achieve this goal, a new generation of wheels was synthesised based on subphthalocyanine fragments which have a bowl shape structure avoiding too many interactions with the surface. The synthesis of a nanovehicle was considered around a polyaromatic core

Entwined dimer formation from self-complementary bis-acridiniums

International audienceThe self-assembling entwined dimer of a bis-acridinium tweezer has been investigated in organic and aqueous media. Please check this proof carefully. Our staff will not read it in detail after you have returned it. Please send your corrections either as a copy of the proof PDF with electronic notes attached or as a list of corrections. Do not edit the text within the PDF or send a revised manuscript as we will not be able to apply your corrections. Corrections at this stage should be minor and not involve extensive changes. Proof corrections must be returned as a single set of corrections, approved by all co-authors. No further corrections can be made after you have submitted your proof corrections as we will publish your article online as soon as possible after they are received. Please ensure that: The spelling and format of all author names and affiliations are checked carefully. You can check how we have identified the authors' first and last names in the researcher information table on the next page. Names will be indexed and cited as shown on the proof, so these must be correct

Synthesis, electronic and photophysical properties of a bisacridinium-Zn(II) porphyrin conjugate

The synthesis of a novel bisacridinium-Zn(II) porphyrin is reported and its properties investigated via electrochemical, photophysical and computational studies. Cyclic voltammetry studies revealed a two-electron oxidation of the Zn(II) porphyrin and the simultaneous one electron reductions of the two acridiniums. Using absorption, emission and ultrafast transient absorption spectroscopies, the near total fluorescence quenching observed following excitation of either the acridinium or Zn(II) porphyrin units was assigned to ultrafast electron transfer (${\le }0.3$ ps) leading to a reduced acridinium and an oxidized porphyrin unit in the bisacridinium-Zn(II) porphyrin conjugate. In addition, computational studies were found to complement experimental results, with calculations revealing two near degenerate HOMOs for the porphyrin

Synthesis, electronic and photophysical properties of a bisacridinium-Zn(II) porphyrin conjugate

The synthesis of a novel bisacridinium-Zn(II) porphyrin is reported and its properties investigated via electrochemical, photophysical and computational studies. Cyclic voltammetry studies revealed a two-electron oxidation of the Zn(II) porphyrin and the simultaneous one electron reductions of the two acridiniums. Using absorption, emission and ultrafast transient absorption spectroscopies, the near total fluorescence quenching observed following excitation of either the acridinium or Zn(II) porphyrin units was assigned to ultrafast electron transfer (${\le }0.3$ ps) leading to a reduced acridinium and an oxidized porphyrin unit in the bisacridinium-Zn(II) porphyrin conjugate. In addition, computational studies were found to complement experimental results, with calculations revealing two near degenerate HOMOs for the porphyrin

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/)

D'un urbanisme de séparation à un urbanisme de mixité

Jacquot Henri. D'un urbanisme de séparation à un urbanisme de mixité. In: Droit et Ville, tome 34, 1992. Colloque de Toulouse (28 et 29 septembre 1992) : Un droit à la ville ? pp. 87-103

Les effets des D.T.A à l’égard des documents et des autorisations d'urbanisme

Jacquot Henri. Les effets des D.T.A à l’égard des documents et des autorisations d'urbanisme. In: Droit et Ville, tome 50, 2000. Colloque : Les Directives Territoriales D'aménagement (Nice-Sofia-Antipolis 24-25 février 2000) pp. 51-67