902 research outputs found

    Return to Play Following Shoulder Stabilization: A Systematic Review and Meta-analysis.

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    BackgroundAnterior shoulder instability can be a disabling condition for the young athlete; however, the best surgical treatment remains controversial. Traditionally, anterior shoulder instability was treated with open stabilization. More recently, arthroscopic repair of the Bankart injury with suture anchor fixation has become an accepted technique.HypothesisNo systematic reviews have compared the rate of return to play following arthroscopic Bankart repair with suture anchor fixation with the Bristow-Latarjet procedure and open stabilization. We hypothesized that the rate of return to play will be similar regardless of surgical technique.Study designSystematic review; Level of evidence, 4.MethodsWe performed a systematic review and meta-analysis focused on return to play following shoulder stabilization. Inclusion criteria included studies in English that reported on rate of return to play and clinical outcomes following primary arthroscopic Bankart repair with suture anchors, the Latarjet procedure, or open stabilization. Statistical analyses included Student t tests and analyses of variance.ResultsSixteen papers reporting on 1036 patients were included. A total of 545 patients underwent arthroscopic Bankart repair with suture anchors, 353 with the Latarjet procedure, and 138 with open repair. No significant difference was found in patient demographic data among the studies. Patients returned to sport at the same level of play (preinjury level) more consistently following arthroscopic Bankart repair (71%) or the Latarjet procedure (73%) than open stabilization (66%) (P < .05). Return to play at any level and postoperative Rowe scores were not significantly different among studies. Recurrent dislocation was significantly less following the Latarjet procedure (3.5%) than after arthroscopic Bankart repair (6.6%) or open stabilization (6.7%) (P < .05).ConclusionThis systematic review demonstrates a greater rate of return to play at the preinjury level following arthroscopic Bankart repair and the Latarjet procedure than open stabilization. Despite this difference, >65% of all treated athletes returned to sport at their preinjury levels, with other outcome measures being similar among the treatment groups. Therefore, arthroscopic Bankart repair, the Latarjet procedure, and open stabilization remain good surgical options in the treatment of the athlete with anterior shoulder instability

    Three-dimensional in situ observations of compressive damage mechanisms in syntactic foam using X-ray microcomputed tomography

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    Royal Society Grant number RG140680 Lloyd's Register Foundation (GB) Oil and Gas Academy of Scotland Open access via Springer Compact AgreementPeer reviewedPublisher PD

    Synthesis of empty bacterial microcompartments, directed organelle protein incorporation, and evidence of filament-associated organelle movement

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    Compartmentalization is an important process, since it allows the segregation of metabolic activities and, in the era of synthetic biology, represents an important tool by which defined microenvironments can be created for specific metabolic functions. Indeed, some bacteria make specialized proteinaceous metabolic compartments called bacterial microcompartments (BMCs) or metabolosomes. Here we demonstrate that the shell of the metabolosome (representing an empty BMC) can be produced within E. coil cells by the coordinated expression of genes encoding structural proteins. A plethora of diverse structures can be generated by changing the expression profile of these genes, including the formation of large axial filaments that interfere with septation. Fusing GFP to PduC, PduD, or PduV, none of which are shell proteins, allows regiospecific targeting of the reporter group to the empty BMC. Live cell imaging provides unexpected evidence of filament-associated BMC movement within the cell in the presence of Pdu

    Operational reliability assessment of the GEOS A spacecraft

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    Decision theory application to GEOS A spacecraft operational reliability assessmen

    Symmetry of high-piezoelectric Pb-based complex perovskites at the morphotropic phase boundary I. Neutron diffraction study on Pb(Zn1/3Nb2/3)O3 -9%PbTiO3

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    The symmetry was examined using neutron diffraction method on Pb(Zn1/3Nb2/3)O3 -9%PbTiO3 (PZN/9PT) which has a composition at the morphotropic phase boundary (MPB) between Pb(Zn1/3Nb2/3)O3 and PbTiO3. The results were compared with those of other specimens with same composition but with different prehistory. The equilibrium state of all examined specimens is not the mixture of rhombohedral and tetragonal phases of the end members but exists in a new polarization rotation line Mc# (orthorhombic-monoclinic line). Among examined specimens, one exhibited tetragonal symmetry at room temperature but recovered monoclinic phase after a cooling and heating cycle

    Solution structure of a bacterial microcompartment targeting peptide and its application in the construction of an ethanol bioreactor

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    Targeting of proteins to bacterial microcompartments (BMCs) is mediated by an 18-amino-acid peptide sequence. Herein, we report the solution structure of the N-terminal targeting peptide (P18) of PduP, the aldehyde dehydrogenase associated with the 1,2-propanediol utilization metabolosome from Citrobacter freundii. The solution structure reveals the peptide to have a well-defined helical conformation along its whole length. Saturation transfer difference and transferred NOE NMR has highlighted the observed interaction surface on the peptide with its main interacting shell protein, PduK. By tagging both a pyruvate decarboxylase and an alcohol dehydrogenase with targeting peptides, it has been possible to direct these enzymes to empty BMCs in vivo and to generate an ethanol bioreactor. Not only are the purified, redesigned BMCs able to transform pyruvate into ethanol efficiently, but the strains containing the modified BMCs produce elevated levels of alcohol

    Exact solution of a linear molecular motor model driven by two-step fluctuations and subject to protein friction

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    We investigate by analytical means the stochastic equations of motion of a linear molecular motor model based on the concept of protein friction. Solving the coupled Langevin equations originally proposed by Mogilner et al. (A. Mogilner et al., Phys. Lett. {\bf 237}, 297 (1998)), and averaging over both the two-step internal conformational fluctuations and the thermal noise, we present explicit, analytical expressions for the average motion and the velocity-force relationship. Our results allow for a direct interpretation of details of this motor model which are not readily accessible from numerical solutions. In particular, we find that the model is able to predict physiologically reasonable values for the load-free motor velocity and the motor mobility.Comment: 12 pages revtex, 6 eps-figure

    Neutron Diffraction Study of Field Cooling Effects on Relaxor Ferroelectrics Pb[(Zn_{1/3} Nb_{2/3})_{0.92} Ti_{0.08}] O_{3}

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    High-temperature (T) and high-electric-field (E) effects on Pb[(Zn_{1/3} Nb_{2/3})_{0.92} Ti_{0.08}]O_3 (PZN-8%PT) were studied comprehensively by neutron diffraction in the ranges 300 <= T <= 550 K and 0 <= E <= 15 kV/cm. We have focused on how phase transitions depend on preceding thermal and electrical sequences. In the field cooling process (FC, E parallel [001] >= 0.5 kV/cm), a successive cubic (C) --> tetragonal (T) --> monoclinic (M_C) transition was observed. In the zero field cooling process (ZFC), however, we have found that the system does not transform to the rhombohedral (R) phase as widely believed, but to a new, unidentified phase, which we call X. X gives a Bragg peak profile similar to that expected for R, but the c-axis is always slightly shorter than the a-axis. As for field effects on the X phase, we found an irreversible X --> M_C transition via another monoclinic phase (M_A) as expected from a previous report [Noheda et al. Phys. Rev. Lett. 86, 3891 (2001)]. At a higher electric field, we confirmed a c-axis jump associated with the field-induced M_C --> T transition, which was observed by strain and x-ray diffraction measurements.Comment: 8 pages, 9 figures, revise

    Diffuse Neutron Scattering Study of a Disordered Complex Perovskite Pb(Zn1/3Nb2/3)O3 Crystal

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    Diffuse scattering around the (110) reciprocal lattice point has been investigated by elastic neutron scattering in the paraelectric and the relaxor phases of the disordered complex perovskite crystal-Pb(Zn1/3Nb2/3)O3(PZN). The appearance of a diffuse intensity peak indicates the formation of polar nanoregions at temperature T*, approximately 40K above Tc=413K. The analysis of this diffuse scattering indicates that these regions are in the shape of ellipsoids, more extended in the direction than in the direction. The quantitative analysis provides an estimate of the correlation length, \xi, or size of the regions and shows that \xi ~1.2\xi , consistent with the primary or dominant displacement of Pb leading to the low temperature rhombohedral phase. Both the appearance of the polar regions at T*and the structural transition at Tc are marked by kinks in the \xi curve but not in the \xi one, also indicating that the primary changes take place in a direction at both temperatures.Comment: REVTeX file. 4 pages, 3 figures embedded, New version after referee cond-mat/010605
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