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101.
Etienne Brachet Jean‐Daniel Brion Mouad Alami Samir Messaoudi 《Advanced Synthesis \u0026amp; Catalysis》2013,355(13):2627-2636
An efficient and unprecedented palladium‐catalyzed S‐glycosylation reaction of a range of alkenyl and alkynyl halides by using thiosugars as nucleophile partners has been established. With palladium diacetate in combination with Xantphos as the catalytic system, a variety of β‐alkenylthioglycosides as well as β‐alkynylthioglycosides can be prepared in good to excellent yields. The efficiency of this general protocol was well‐demonstrated by the formal synthesis of a leaf‐closure β‐glucosidase inhibitor.
102.
For the first time, chemical analyses using Atom Probe Tomography were performed on a bolt made of cold worked 316 austenitic stainless steel, extracted from the internal structures of a pressurized water reactor after 17 years of reactor service. The irradiation temperature of these samples was 633 K and the irradiation dose was estimated to 12 dpa (7.81 × 1025 neutrons.m−2, E > 1 MeV). The samples were analysed with a laser assisted tomographic atom probe. These analyses have shown that neutron irradiation has a strong effect on the intragranular distribution of solute atoms. A high number density (6 × 1023 m−3) of Ni-Si enriched and Cr-Fe depleted clusters was detected after irradiation. Mo and P segregations at the interfaces of these clusters were also observed. Finally, Si enriched atmospheres were seen. 相似文献
103.
104.
Etienne Buscail Guillaume Le Cosquer Fabian Gross Marine Lebrin Laetitia Bugarel Cline Deraison Nathalie Vergnolle Barbara Bournet Cyrielle Gilletta Louis Buscail 《International journal of molecular sciences》2021,22(18)
Between 20 to 25% of Crohn’s disease (CD) patients suffer from perianal fistulas, a marker of disease severity. Seton drainage combined with anti-TNFα can result in closure of the fistula in 70 to 75% of patients. For the remaining 25% of patients there is room for in situ injection of autologous or allogenic mesenchymal stem cells such as adipose-derived stem/stromal cells (ADSCs). ADSCs exert their effects on tissues and effector cells through paracrine phenomena, including the secretome and extracellular vesicles. They display anti-inflammatory, anti-apoptotic, pro-angiogenic, proliferative, and immunomodulatory properties, and a homing within the damaged tissue. They also have immuno-evasive properties allowing a clinical allogeneic approach. Numerous clinical trials have been conducted that demonstrate a complete cure rate of anoperineal fistulas in CD ranging from 46 to 90% of cases after in situ injection of autologous or allogenic ADSCs. A pivotal phase III-controlled trial using allogenic ADSCs (Alofisel®) demonstrated that prolonged clinical and radiological remission can be obtained in nearly 60% of cases with a good safety profile. Future studies should be conducted for a better knowledge of the local effect of ADSCs as well as for a standardization in terms of the number of injections and associated procedures. 相似文献
105.
Using the theory described in the preliminary publication, the isothermal grain growth of a low carbon, silicon‐manganese bearing TRIP‐steel has been studied. The austenitic grain size was established through the measurement of the mean linear intercept distance, which has been transformed into the real mean austenite grain size. A general model of the form dn=d0n+K1t exp(K2/T) was used and the coefficients n, K1 and K2 have been statistically determined. It has been demonstrated that for low annealing temperatures the value of n is situated around 6, whereas at high temperatures n rapidly drops and adopts a value of 2. This behaviour was related to the dissolution of the precipitates present in the austenitic matrix during the soaking treatments. The model delivers very good predictions for soaking temperatures up to 1200 °C. For higher temperatures, the deviations between the predicted grain size and the really measured one are higher. 相似文献
106.
Exploiting group symmetry in truss topology optimization 总被引:1,自引:0,他引:1
Yanqin Bai Etienne de Klerk Dmitrii Pasechnik Renata Sotirov 《Optimization and Engineering》2009,10(3):331-349
We consider semidefinite programming (SDP) formulations of certain truss topology optimization problems, where a lower bound
is imposed on the fundamental frequency of vibration of the truss structure. These SDP formulations were introduced in Ohsaki
et al. (Comp. Meth. Appl. Mech. Eng. 180:203–217, 1999). We show how one may automatically obtain symmetric designs, by eliminating the ‘redundant’ symmetry in the SDP problem
formulation. This has the advantage that the original SDP problem is substantially reduced in size for trusses with large
symmetry groups. 相似文献
107.
Arthur Stricher Loïc Picard Brice Gabrielle Etienne Delebecq François Ganachaud 《Polymer International》2016,65(6):713-720
This paper is devoted to the characterization and processing of high molar mass vinyl‐bearing polysiloxanes in high consistency silicone rubber (HCR) formulations. The molar masses of five different polydimethylsiloxane gums, bearing vinyl groups at the ends and along their chains, were evaluated by size exclusion chromatography and rheometry. 29Si and 1H NMR spectroscopy allowed the precise determination of the vinyl content and of the distribution in the different polymers. Typical HCRs formulated from these gums were heat‐cured to process silicone rubber materials that were then tested mechanically. The macromolecular properties were correlated to the final material network structure. The amount of reactive vinyl moieties, rather than their distribution along or at the end of chains, is a key parameter to tailor the material mechanical properties. © 2016 Society of Chemical Industry 相似文献
108.
Kostantine Katcko Etienne Urbain Franck Ngassam Lalit Kandpal Bhavishya Chowrira Filip Schleicher Ufuk Halisdemir Di Wang Torsten Scherer Damien Mertz Benoit Leconte Nicolas Beyer Daniel Spor Pierre Panissod Arnaud Boulard Jacek Arabski Christophe Kieber Emmanuel Sternitzky Victor Da Costa Michel Hehn François Montaigne Armel Bahouka Wolfgang Weber Eric Beaurepaire Christian Kübel Daniel Lacour Mébarek Alouani Samy Boukari Martin Bowen 《Advanced functional materials》2021,31(15):2009467
The quantum states of nano-objects can drive electrical transport properties across lateral and local-probe junctions. This raises the prospect, in a solid-state device, of electrically encoding information at the quantum level using spin-flip excitations between electron spins. However, this electronic state has no defined magnetic orientation and is short-lived. Using a novel vertical nanojunction process, these limitations are overcome and this steady-state capability is experimentally demonstrated in solid-state spintronic devices. The excited quantum state of a spin chain formed by Co phthalocyanine molecules coupled to a ferromagnetic electrode constitutes a distinct magnetic unit endowed with a coercive field. This generates a specific steady-state magnetoresistance trace that is tied to the spin-flip conductance channel, and is opposite in sign to the ground state magnetoresistance term, as expected from spin excitation transition rules. The experimental 5.9 meV thermal energy barrier between the ground and excited spin states is confirmed by density functional theory, in line with macrospin phenomenological modeling of magnetotransport results. This low-voltage control over a spin chain's quantum state and spintronic contribution lay a path for transmitting spin wave-encoded information across molecular layers in devices. It should also stimulate quantum prospects for the antiferromagnetic spintronics and oxides electronics communities. 相似文献
109.
François Pernot Pascal Etienne Frédéric Boschet Lucien Datas 《Journal of the American Ceramic Society》1999,82(3):641-648
The strengths of porous phosphate glass-ceramic specimens, with relative densities ranging between 0.25 and 0.50, were measured by four-point bending at room temperature. An analysis of the data, using Weibull statistics, indicated that such a treatment, usually performed on dense ceramics, can also be used on porous materials. In the sets studied, the nature of critical flaws was determined, which led to the proposal of a mechanism of fracture initiation in such porous materials. 相似文献
110.
Alessandro Sannino Dr. Elena Gabriele Martina Bigatti Dr. Sara Mulatto Dr. Jacopo Piazzi Dr. Jörg Scheuermann Prof. Dr. Dario Neri Dr. Etienne J. Donckele Dr. Florent Samain 《Chembiochem : a European journal of chemical biology》2019,20(7):955-962
DNA-encoded chemical libraries are often used for the discovery of ligands against protein targets of interest. These large collections of DNA-barcoded chemical compounds are typically screened by using affinity capture methodologies followed by PCR amplification and DNA sequencing procedures. However, the performance of individual steps in the selection procedures has been scarcely investigated, so far. Herein, the quantitative analysis of selection experiments, by using three ligands with different affinity to carbonic anhydrase IX as model compounds, is described. In the first set of experiments, quantitative PCR (qPCR) procedures are used to evaluate the recovery and selectivity for affinity capture procedures performed on different solid-phase supports, which are commonly used for library screening. In the second step, both qPCR and analysis of DNA sequencing results are used to assess the recovery and selectivity of individual carbonic anhydrase IX ligands in a library, containing 360 000 compounds. Collectively, this study reveals that selection procedures can be efficient for ligands with sub-micromolar dissociation constants to the target protein of interest, but also that selection performance dramatically drops if 104 copies per library member are used as the input. 相似文献