Quasiparticle interfacial level alignment of highly hybridized frontier levels: H2_2O on TiO2_2(110)

Knowledge of the frontier levels' alignment prior to photo-irradiation is necessary to achieve a complete quantitative description of H$_2$O photocatalysis on TiO$_2$(110). Although H$_2$O on rutile TiO$_2$(110) has been thoroughly studied both experimentally and theoretically, a quantitative value for the energy of the highest H$_2$O occupied levels is still lacking. For experiment, this is due to the H$_2$O levels being obscured by hybridization with TiO$_2$(110) levels in the difference spectra obtained via ultraviolet photoemission spectroscopy (UPS). For theory, this is due to inherent difficulties in properly describing many-body effects at the H$_2$O-TiO$_2$(110) interface. Using the projected density of states (DOS) from state-of-the-art quasiparticle (QP) $G_0W_0$, we disentangle the adsorbate and surface contributions to the complex UPS spectra of H$_2$O on TiO$_2$(110). We perform this separation as a function of H$_2$O coverage and dissociation on stoichiometric and reduced surfaces. Due to hybridization with the TiO$_2$(110) surface, the H$_2$O 3a$_1$ and 1b$_1$ levels are broadened into several peaks between 5 and 1 eV below the TiO$_2$(110) valence band maximum (VBM). These peaks have both intermolecular and interfacial bonding and antibonding character. We find the highest occupied levels of H$_2$O adsorbed intact and dissociated on stoichiometric TiO$_2$(110) are 1.1 and 0.9 eV below the VBM. We also find a similar energy of 1.1 eV for the highest occupied levels of H$_2$O when adsorbed dissociatively on a bridging O vacancy of the reduced surface. In both cases, these energies are significantly higher (by 0.6 to 2.6 eV) than those estimated from UPS difference spectra, which are inconclusive in this energy region. Finally, we apply self-consistent QP$GW$ (scQP$GW$1) to obtain the ionization potential of the H$_2$O-TiO$_2$(110) interface.Comment: 12 pages, 12 figures, 1 tabl

Traitement chirurgical des métastases osseuses diaphysaires des os longs (Etude rétrospective à propos de 76 cas)

BESANCON-BU Médecine pharmacie (250562102) / SudocSudocFranceF

Bone morphogenetic proteins in soft-tissue reconstruction.

International audienceDifferent options are reviewed in the field of musculoskeletal tissue reconstruction, from the addition of biological actors (cells, growth factors, biological or artificial scaffolds) to the application of gene therapy or tissue engineering. Growth factors can enable innovative solutions to treat such disease if we can extrapolate to soft tissue the promising results obtained in bone reconstruction with bone morphogenetic proteins. However, as in bone reconstruction, soft-tissue regeneration will depend on the drug delivery carrier, the scaffold for the newly formed tissue, the dose of growth factor and the animal model, which must all be explored before extrapolation to clinical problems

[Articular reconstructions by a costochondral grafting (or osteochondral costal grafting)]

International audienceWe describe a novel technique of costochondral autografting for the treatment of trapeziometacarpal arthritis, radioscaphoid osteoarthritis, malunion of the distal end of the radius, and osteoarticular loss of the MP joints of long fingers. The costal graft harvest technique is always the same. A 5-cm horizontal incision is made over the 9th rib, and the rib is exposed at the osteocartilaginous junction. Cartilaginous grafts are harvested with a scalpel, and osteocartilaginous grafts with a saw. Since 1992, 116 patients with trapezio-metacarpal arthritis have been treated by partial trapeziectomy and autologous rib cartilage grafting. One hundred patients were reviewed with an average follow-up of 5.6 years. The results were better than those of trapeziectomy with tendon interposition or ligamentous reconstruction, owing to good stability of the thumb ray height. For the treatment of radioscaphoid osteoarthritis following scaphoid non union or chronic scapholunate instability, partial carpal arthrodesis and resection of the first row are the classical techniques. As an alternative to these procedures, 18 patients were treated by resection of the proximal portion of the scaphoid and insertion of an osteochondral costal autograft. Mean follow-up is 4.1 years. The results are excellent or good in 15 cases, fair in 2 cases, and poor in 1 case (luxation of the graft). Four patients with articular malunion of the distal radius received an osteocartilaginous costal graft to reconstruct the articular surface of the radius while avoiding partial or total arthrodesis of the wrist. Four patients with segmental osteoarticular loss of the longfingers were treated with the same technique, thereby avoiding silicone arthroplasty. We review the literature on cartilaginous rib grafts in maxillofajcial and orthopaedic surgery. In our experience, MRI and biopsy show viable cartilage but also histologic changes such as revascularization, fibrous transformation and bone metaplasia

Micro-indentation and coupling test-calculations for identification by inverse method of non linear behavior of human femoral head cartilage

International audienc

Shape Persistence of Polyproline II Helical Oligoprolines

Oligoprolines are commonly used as molecular scaffolds. Past studies on the persistence length of their secondary structure, the polyproline II (PPII) helix, and on the fraction of backbone cis amide bonds have provided conflicting results. We resolved this debate by studying a series of spin-labeled proline octadecamers with EPR spectroscopy. Distance distributions between an N-terminal GdIII-DOTA (DOTA=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) label and a nitroxide label at one of five evenly spaced backbone sites allowed us to discriminate between the flexibility of the PPII helix and the cis amide contributions. An upper limit of 2% cis amide bonds per residue was found in a 7:3 (v/v) water/glycerol mixture, whereas cis amides were not observed in trifluoroethanol. Extrapolation of Monte Carlo models from the glass transition to ambient temperature predicts a persistence length of ≈3-3.5 nm in both solvents. The method is generally applicable to any type of oligomer for which the persistence length is of interest

La tige Avenir® non cimentée recouverte d'hydroxyapatite en milieu septique dans la reprise de prothèse totale de hanche infectée : à propos de 40 cas

Does the implantation of an uncemented hydroxyapatite-coated first-line stem in a septic environment during a one-stage total hip arthroplasty revision (THAR) for periprosthetic joint infection on total hip arthroplasty provide good results in terms of healing the infection and osteointegration of the stem ?We retrospectively reviewed 40 patients operated on for septic THAR with placement of the cementless Avenir® stem - between 2008 and 2018 at the Besançon University Hospital - with a minimum follow-up of 2 years necessary to define cure in the absence of infectious recurrence. Clinical outcome was assessed using the Harris, Oxford and Merle D'Aubigné scores. Osteointegration was analyzed by the Enhg radiographic score. Mean follow-up was 4.5 years (0-11). Cure of infection was achieved in 35 of 40 (87.5%). The median Harris score was 74/100, Oxford score 45/60, and Merle d'Aubigné score 15/18. Of 37 femoral stems, 36 (97%) had radiographically stable osteointegration. An age of 80 years is a risk factor for failure of septic THAR with implantation of an uncemented stem in one stage.The cementless Avenir® stem has its place in one-stage septic THAR. It gives good results on the healing of the infection and the integration of the stem in the context of femoral bone loss rated Paprosky 1.L’implantation en milieu septique d’une tige de première intention non cimentée recouverte d’hydroxyapatite lors d’une reprise de prothèse totale de hanche (RPTH) infectée en 1 temps opératoire donne-t-elle de bons résultats sur la guérison de l’infection et l’ostéointégration de la tige ?Nous avons examiné rétrospectivement 40 patients opérés d’une RPTH septique avec pose de la tige Avenir® sans ciment - entre 2008 et 2018 au CHRU de Besançon - avec un suivi minimum de 2 ans nécessaire pour définir la guérison en l’absence de récidive infectieuse. Le résultat clinique a été évalué à l'aide des scores de Harris, Oxford et Merle D'Aubigné. L’ostéointégration a été analysé par le score radiographique de Enhg. Le suivi moyen était de 4,5 ans (0-11). La guérison de l’infection a été obtenue chez 35 des 40 (87,5 %). Le score médian de Harris était de 74/100, celui de Oxford de 45/60 et celui de Merle d’Aubigné de 15/18. Sur 37 tiges fémorales, 36 (97 %) avaient une ostéointégration radiographiquement stable. Un âge de 80 ans est un facteur de risque d’échec de la RPTH septique avec implantation d’une tige non cimentée en 1 temps.La tige Avenir® sans ciment a sa place dans la RPTH septique en 1 temps. Elle donne de bons résultats sur la guérison de l’infection et l’intégration de la tige dans le cadre de pertes de substances osseuses fémorales cotées Paprosky 1

Corrigendum to: Shape Persistence of Polyproline II Helical Oligoprolines (Chem. Eur. J., (2015), 21, 10.1002/chem.201501190)

It has been brought to author’s attention that lowest line of subplots in Figure 3 was erroneously swapped with the upper line of subplots in Figure 4. Figure captions in the article are correct for the figures given below. (Figure Presented.)

La tige Avenir® non cimentée recouverte d'hydroxyapatite en milieu septique dans la reprise de prothèse totale de hanche infectée : à propos de 40 cas

Does the implantation of an uncemented hydroxyapatite-coated first-line stem in a septic environment during a one-stage total hip arthroplasty revision (THAR) for periprosthetic joint infection on total hip arthroplasty provide good results in terms of healing the infection and osteointegration of the stem ?We retrospectively reviewed 40 patients operated on for septic THAR with placement of the cementless Avenir® stem - between 2008 and 2018 at the Besançon University Hospital - with a minimum follow-up of 2 years necessary to define cure in the absence of infectious recurrence. Clinical outcome was assessed using the Harris, Oxford and Merle D'Aubigné scores. Osteointegration was analyzed by the Enhg radiographic score. Mean follow-up was 4.5 years (0-11). Cure of infection was achieved in 35 of 40 (87.5%). The median Harris score was 74/100, Oxford score 45/60, and Merle d'Aubigné score 15/18. Of 37 femoral stems, 36 (97%) had radiographically stable osteointegration. An age of 80 years is a risk factor for failure of septic THAR with implantation of an uncemented stem in one stage.The cementless Avenir® stem has its place in one-stage septic THAR. It gives good results on the healing of the infection and the integration of the stem in the context of femoral bone loss rated Paprosky 1.L’implantation en milieu septique d’une tige de première intention non cimentée recouverte d’hydroxyapatite lors d’une reprise de prothèse totale de hanche (RPTH) infectée en 1 temps opératoire donne-t-elle de bons résultats sur la guérison de l’infection et l’ostéointégration de la tige ?Nous avons examiné rétrospectivement 40 patients opérés d’une RPTH septique avec pose de la tige Avenir® sans ciment - entre 2008 et 2018 au CHRU de Besançon - avec un suivi minimum de 2 ans nécessaire pour définir la guérison en l’absence de récidive infectieuse. Le résultat clinique a été évalué à l'aide des scores de Harris, Oxford et Merle D'Aubigné. L’ostéointégration a été analysé par le score radiographique de Enhg. Le suivi moyen était de 4,5 ans (0-11). La guérison de l’infection a été obtenue chez 35 des 40 (87,5 %). Le score médian de Harris était de 74/100, celui de Oxford de 45/60 et celui de Merle d’Aubigné de 15/18. Sur 37 tiges fémorales, 36 (97 %) avaient une ostéointégration radiographiquement stable. Un âge de 80 ans est un facteur de risque d’échec de la RPTH septique avec implantation d’une tige non cimentée en 1 temps.La tige Avenir® sans ciment a sa place dans la RPTH septique en 1 temps. Elle donne de bons résultats sur la guérison de l’infection et l’intégration de la tige dans le cadre de pertes de substances osseuses fémorales cotées Paprosky 1