L'Écho : grand quotidien d'information du Centre Ouest

30 août 19221922/08/30 (A51).Appartient à l’ensemble documentaire : PoitouCh

Muscle contributions to medial tibiofemoral compartment contact loading following ACL reconstruction using semitendinosus and gracilis tendon grafts

This data contains outputs of muscle force, activations, torques, fiber lengths and joint contact forces of 34 MTU's for 25 participants each doing 3 walks, 3 runs and 3 cuts. Data for Standard model and an adjusted model, that models the morbidity associated wit

Adhesion, Stiffness, and Instability in Atomically Thin MoS₂ Bubbles

We measured the work of separation of single and few-layer MoS₂ membranes from a SiO_<i>x</i> substrate using a mechanical blister test and found a value of 220 ± 35 mJ/m². Our measurements were also used to determine the 2D Young’s modulus (<i>E</i>_2D) of a single MoS₂ layer to be 160 ± 40 N/m. We then studied the delamination mechanics of pressurized MoS₂ bubbles, demonstrating both stable and unstable transitions between the bubbles’ laminated and delaminated states as the bubbles were inflated. When they were deflated, we observed edge pinning and a snap-in transition that are not accounted for by the previously reported models. We attribute this result to adhesion hysteresis and use our results to estimate the work of adhesion of our membranes to be 42 ± 20 mJ/m²

Alkynyl-naphthalimide Fluorophores: Gold Coordination Chemistry and Cellular Imaging Applications

A range of fluorescent alkynyl-naphthalimide fluorophores has been synthesized and their photophysical properties examined. The fluorescent ligands are based upon a 4-substituted 1,8-naphthalimide core and incorporate structural variations (at the 4-position) to tune the amphiphilic character: chloro (<b>L1</b>), 4-[2-(2-aminoethoxy)­ethanol] (<b>L2</b>), 4-[2-(2-methoxyethoxy)­ethylamino] (<b>L3</b>), piperidine (<b>L4</b>), morpholine (<b>L5</b>), 4-methylpiperidine (<b>L6</b>), and 4-piperidone ethylene ketal (<b>L7</b>) variants. The amino-substituted species (<b>L2</b>–<b>L7</b>) are fluorescent in the visible region at around 517–535 nm through a naphthalimide-localized intramolecular charge transfer (ICT), with appreciable Stokes’ shifts of ca. 6500 cm^–1 and lifetimes up to 10.4 ns. Corresponding two-coordinate Au­(I) complexes [Au­(L)­(PPh₃)] were isolated, with X-ray structural studies revealing the expected coordination mode via the alkyne donor. The Au­(I) complexes retain the visible fluorescence associated with the coordinated alkynyl-naphthalimide ligand. The ligands and complexes were investigated for their cytotoxicity across a range of cell lines (LOVO, MCF-7, A549, PC3, HEK) and their potential as cell imaging agents for HEK (human embryonic kidney) cells and Spironucleus vortens using confocal fluorescence microscopy. The images reveal that these fluorophores are highly compatible with fluorescence microscopy and show some clear intracellular localization patterns that are dependent upon the specific nature of the naphthalimide substituent

Fluorescent Rhenium-Naphthalimide Conjugates as Cellular Imaging Agents

A range of biologically compatible, fluorescent rhenium-naphthalimide conjugates, based upon the rhenium <i>fac</i>-tricarbonyl core, has been synthesized. The fluorescent ligands are based upon a N-functionalized, 4-amino-derived 1,8-naphthalimide core and incorporate a dipicolyl amine binding unit to chelate Re­(I); the structural variations accord to the nature of the alkylated imide with ethyl ester glycine (<b>L</b>^<b>1</b>), 3-propanol (<b>L</b>^<b>2</b>), diethylene glycol (<b>L</b>^<b>3</b>), and benzyl alcohol (<b>L</b>^<b>4</b>) variants. The species are fluorescent in the visible region between 505 and 537 nm through a naphthalimide-localized intramolecular charge transfer, with corresponding fluorescent lifetimes of up to 9.8 ns. The ligands and complexes were investigated for their potential as imaging agents for human osteoarthritic cells and protistan fish parasite <i>Spironucleus vortens</i> using confocal fluorescence microscopy. The results show that the specific nature of the naphthalimide structure serves to control the uptake and intracellular localization of these imaging agents. Significant differences were noted between the free ligands and complexes, with the Re­(I) complex of <b>L</b>^<b>2</b> showing hydrogenosomal localization in <i>S. vortens</i>

Fluorescent Rhenium-Naphthalimide Conjugates as Cellular Imaging Agents

A range of biologically compatible, fluorescent rhenium-naphthalimide conjugates, based upon the rhenium <i>fac</i>-tricarbonyl core, has been synthesized. The fluorescent ligands are based upon a N-functionalized, 4-amino-derived 1,8-naphthalimide core and incorporate a dipicolyl amine binding unit to chelate Re­(I); the structural variations accord to the nature of the alkylated imide with ethyl ester glycine (<b>L</b>^<b>1</b>), 3-propanol (<b>L</b>^<b>2</b>), diethylene glycol (<b>L</b>^<b>3</b>), and benzyl alcohol (<b>L</b>^<b>4</b>) variants. The species are fluorescent in the visible region between 505 and 537 nm through a naphthalimide-localized intramolecular charge transfer, with corresponding fluorescent lifetimes of up to 9.8 ns. The ligands and complexes were investigated for their potential as imaging agents for human osteoarthritic cells and protistan fish parasite <i>Spironucleus vortens</i> using confocal fluorescence microscopy. The results show that the specific nature of the naphthalimide structure serves to control the uptake and intracellular localization of these imaging agents. Significant differences were noted between the free ligands and complexes, with the Re­(I) complex of <b>L</b>^<b>2</b> showing hydrogenosomal localization in <i>S. vortens</i>