The global percutaneous shuttling technique tip for arthroscopic rotator cuff repair

Most arthroscopic rotator cuff repairs utilize suture passing devices placed through arthro- scopic cannulas. These devices are limited by the size of the passing device where the suture is passed through the tendon. An alternative technique has been used in the senior author’s practice for the past ten years, where sutures are placed through the rotator cuff tendon using percutaneous passing devices. This technique, dubbed the global percutaneous shuttling technique of rotator cuff repair, affords the placement of sutures from nearly any angle and location in the shoulder, and has the potential advantage of larger suture bites through the tendon edge. These advantages may increase the area of tendon available to compress to the rotator cuff footprint and improve tendon healing and outcomes. The aim of this study is to describe the global percutaneous shuttling (GPS) technique and report our results using this method. The GPS technique can be used for any full thickness rotator cuff tear and is particularly useful for massive cuff tears with poor tissue quality. We recently followed up 22 patients with an average follow up of 32 months to validate its usefulness. American Shoulder and Elbow Surgeons scores improved significantly from 37 preoperatively to 90 postoperatively (P<0.0001). This data supports the use of the GPS technique for arthroscopic rotator cuff repair. Further biomechanical studies are currently being performed to assess the improvements in tendon footprint area with this technique

Electrochemical Synthesis of Bismuth Iodide and Bismuth Oxyiodide

This study reports the electrochemical synthesis of bismuth iodide and bismuth oxyiodide from acidic baths containing bismuth nitrate, sodium nitrate, iodine and ethylene glycol by a simple pH control. Linear sweep voltammetry analyses determined the potential window for the reduction of iodine where bismuth ion does not get reduced. The concentration of the iodide ions in the bath is regulated by the applied potential and the equilibrium that exists between iodine-iodide and nitrate-nitrite pairs. At pH 0.2 and 0.5, bismuth is predominantly present as free Bi3+ ions, which react with iodide to form bismuth triiodide. On the other hand, even at slightly elevated pH 1.0 and 2.0, bismuth is predominantly complexed by water, nitrates and ethylene glycol. These complexes react with the iodide ions to form bismuth oxyiodide. X-ray diffraction confirms that bismuth oxyiodide is predominantly formed at higher pH (1.0 and 2.0), while at lower pH (0.2 and 0.5), bismuth triiodide is formed. Impedance spectra are consistent with the above mechanism. The deposited bismuth oxyiodide films exhibit a cactus-like morphology formed from interlinked nano-disks, while the bismuth iodide films form micron-size platelet crystallites, both with good surface coverage. X-ray photoelectron spectroscopy confirms the formation of pure BiI3 at pH 0.2, while binding energies of Bi 4f state in pure BiOI prepared at pH 2.0 has a slight shift towards higher binding energies. From diffuse reflectance spectroscopy studies, indirect bandgaps of electrochemically synthesized BiI3 and BiOI were found to be 1.72 eV and 1.98 eV, respectively

MPI/FT TM: Architecture and Taxonomies for Fault-Tolerant, Message-Passing Middleware for Performance-Portable Parallel Computing *Work performed in part with support from NASA under

MPI has proven effective for parallel applications in situations with neither QoS nor fault handling. Emerging environments motivate fault-tolerant MPI middleware. Environments include space-based, wide-area/web/meta computing, and scalable clusters. MPI/FT, the system described here, trades off sufficient MPI fault coverage against acceptable parallel performance, based on mission requirements and constraints. MPI codes are evolved to use MPI/FT features. Non-portable code for event handlers and recovery management is isolated

Effects of Additives on Kinetics, Morphologies and Lead-Sensing Property of Electrodeposited Bismuth Films

This study presents a systematic examination of the effects of bath additives and deposition conditions on the rates of electrodeposition of bismuth, obtained morphologies, and the ability of the bismuth films to detect trace concentrations of lead. Novel morphologies of bismuth are reported for the first time. The bath comprises bismuth nitrate, nitric acid, and a set of additives, viz., citric acid (complexant), poly­(vinyl alcohol) (surface inhibitor), and betaine (grain refiner). Rotating disk electrode voltammetry and cyclic voltammetry have been used to determine the mechanism and rates of bismuth electrodeposition. Scanning electron microscopy is used to study deposit morphologies, while X-ray diffraction and X-ray photoelectron spectroscopy have been used to examine crystallinity and composition of the deposited thin films. Even in the presence of additives, it is seen that bismuth deposition is diffusion-controlled process with progressive nucleation–growth of crystallites, and the reduction is a single-step, three-electron-transfer, quasi-reversible reaction. The films deposited from the bath without additives comprise micrometer-sized, hexagonal rods with controlled aspect ratios (1.83–2.05). Baths containing citric acid produce films with flower-like structures and cracked grains, but with poor adhesion to copper substrate. Introducing poly­(vinyl alcohol) significantly slows down bismuth deposition, increases the number of nuclei, produces cauliflower-like crystallites, and promotes adhesion to copper. Betaine smoothens these crystallites while retaining good adhesion. Pulsing the deposition current promotes growth of existing nuclei. In the absence of additives, fused flat disk-type spindles are seen. In the presence of additives, pulsed deposition results in sea-urchin-like morphologies. Adhesion of bismuth onto copper impacts the ability of the film to detect trace concentration of Pb²⁺ ions in aqueous solutions using anodic stripping voltammetry. The films obtained from baths with additives through direct current plating show the best sensor response for 50 ppb Pb²⁺

Implementing stakeholder engagement to explore alternative models of consent: An example from the PREP-IT trials

Introduction: Cluster randomized crossover trials are often faced with a dilemma when selecting an optimal model of consent, as the traditional model of obtaining informed consent from participant's before initiating any trial related activities may not be suitable. We describe our experience of engaging patient advisors to identify an optimal model of consent for the PREP-IT trials. This paper also examines surrogate measures of success for the selected model of consent. Methods: The PREP-IT program consists of two multi-center cluster randomized crossover trials that engaged patient advisors to determine an optimal model of consent. Patient advisors and stakeholders met regularly and reached consensus on decisions related to the trial design including the model for consent. Patient advisors provided valuable insight on how key decisions on trial design and conduct would be received by participants and the impact these decisions will have. Results: Patient advisors, together with stakeholders, reviewed the pros and cons and the requirements for the traditional model of consent, deferred consent, and waiver of consent. Collectively, they agreed upon a deferred consent model, in which patients may be approached for consent after their fracture surgery and prior to data collection. The consent rate in PREP-IT is 80.7%, and 0.67% of participants have withdrawn consent for participation. Discussion: Involvement of patient advisors in the development of an optimal model of consent has been successful. Engagement of patient advisors is recommended for other large trials where the traditional model of consent may not be optimal