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Objectives: This study compares the responsiveness, or the ability to detect clinical change in a disease, between the generic Short Form-36 (SF-36) and musculoskeletal specific Short Musculoskeletal Functional Assessment (SMFA) patient-reported outcome measures (PROMs) in the orthopaedic trauma population. Stratified analysis was performed to compare whether responsiveness differs between patients with single or multiple orthopaedic injuries. Design: Prospective case series. Setting: Level 1 Trauma Center. Patients: A total of 659 patients with orthopaedic trauma injuries to the pelvis, acetabulum, or tibia were included for analysis. There were 485 patients with a single isolated injury and 174 patients with multiple orthopaedic injuries. Intervention: None. Main Outcome Measurements: Responsiveness was calculated through the standard response mean (SRM), the proportion meeting a minimal clinically important difference, and floor and ceiling effects. Results: Between baseline and 6 months the magnitude of the SRM for SF-36 was consistently greater than that of SMFA in patients with single (P

Staphylococcus aureus, a major human pathogen, exacerbates allergic disorders, including atopic dermatitis, nasal polyps\ud and asthma, which are characterized by tissue eosinophilia. Eosinophils, via their destructive granule contents, can cause\ud significant tissue damage, resulting in inflammation and further recruitment of inflammatory cells. We hypothesised that the\ud relationship between S. aureus and eosinophils may contribute to disease pathology. We found that supernatants from S.\ud aureus (SH1000 strain) cultures cause rapid and profound eosinophil necrosis, resulting in dramatic cell loss within 2 hours.\ud This is in marked contrast to neutrophil granulocytes where no significant cell death was observed (at equivalent dilutions).\ud Supernatants prepared from a strain deficient in the accessory gene regulator (agr) that produces reduced levels of many\ud important virulence factors, including the abundantly produced a-hemolysin (Hla), failed to induce eosinophil death. The\ud role of Hla in mediating eosinophil death was investigated using both an Hla deficient SH1000-modified strain, which did\ud not induce eosinophil death, and purified Hla, which induced concentration-dependent eosinophil death via both apoptosis\ud and necrosis. We conclude that S. aureus Hla induces aberrant eosinophil cell death in vitro and that this may increase tissue\ud injury in allergic disease.

The corrosion behavior of several commercial aluminum sacrificial anode alloys were studied. Laboratory-scale experiments were conducted to establish the galvanic current output characteristics of the alloys when coupled to HY-80 steel in synthetic seawater. Also direct weight loss measurements of corrosion rates and potentiostatic polarization behavior were obtained, and the mode and distribution of corrosive attack on the various anode alloys were studied by scanning electron microscopy. All the alloys studied show similar galvanic current characteristics as a function of time, with an initially high current density which falls of to a stable value, primarily due to the accumulation of calcareous deposits on the cathodes. The corrosion patterns developed by each alloy are distinctly different, both on the macroscopic and microscopic scale. The commercial alloy Galvalum I macroscopically exhibits attack preferentially on specimen edges, while Reynode II tends to form vertically elongated dissolution cavities on the broad specimen surfaces, and KA-90 tends to profusely pit. These different behaviors can be rationalized in terms of the observed anodic polarization characteristics of the respective alloys. All the alloys show distinct crystallographic attack on the microscopic scale, but the details of dissolution morphology are quite different for each alloy. Office of Naval Research http://archive.org/details/corrosionbehavio00perk supported by the Office of Naval Research, Naval Ship Systems Command, Metallurgy Program Office, Code 471, Arlington, VA, 22217, through Contract No. N00014-78-WR-80105, NR-036-120. NA Approved for public release; distribution is unlimited.

The galvanic corrosion behavior of 5086 aluminum alloy in three tempers {Hll6, Hll7, H32) when coupled with more noble metals {1040 steel, naval brass, and Ti-150A titanium) and immersed in aerated synthetic seawater, was studied. Galvanic current density measurements, potentiodynamic polarization determinations, and optical and electron microscopic observations were made. Galvanic corrosion of 5086 aluminum was found to be independent of temper and to decrease in the order (of coupled metals) Ti > naval brass> 1040 steel. The effect of dissimilar metal coupling decreases with time due to the formation of corrosion or product deposits on both anodic and cathodic surfaces. Coverage of the surface of the aluminum (anodic) member of couples with corrosion products tends to promote the operation of local corrosion modes. Correlations have been made between corrosion product distribution and the distribution of dissolution attack by microscopic means, and the relation of these features to potential distribution is discussed. Naval Research, Metallurgy Program Office, Code 471 N00014-77-WR-70215, NR-036-120 Approved for public release; distribution is unlimited.

The effects of turbulent flow on the corrosion behavior of 90/10 Cu-Ni were studied experimentally in synthetic seawater electrolyte, using a circling foil apparatus at relative velocities up to about 6 m/sec. The flow field at the specimen surface was characterized by anemometric methods. Corrosion rates were determined by direct weight loss and by several electrochemical methods, including the linear polarization method and from Tafel plots; also zero resistance ammeter measurements were made on galvanic couples. Consideration was given to the question of the appropriate analytical approach to velocity (fluid flow) effects on corrosion processes. The contribution of convective diffusion is considered dominant over the velocity range studied, and the rate of eddy diffusivity (fine flow structure effects on mass transport) is described. The separate electrochemical and mechanical influences of high-intensity turbulent flows are considered. Office of Naval Research Metallurgy Program Office, Code 471 N00014-78-WR-80105, NR-036-120 Approved for public release; distribution is unlimited.