5 research outputs found
Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures
Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo
Measuring the photoelectron emission delay in the molecular frame
If matter absorbs a photon of sufficient energy it emits an electron. The
question of the duration of the emission process has intrigued scientists for
decades. With the advent of attosecond metrology, experiments addressing such
ultrashort intervals became possible. While these types of studies require
attosecond experimental precision, we present here a novel measurement approach
that avoids those experimental difficulties. We instead extract the emission
delay from the interference pattern generated as the emitted photoelectron is
diffracted by the parent ion's potential. Targeting core electrons in CO, we
measured a 2d map of photoelectron emission delays in the molecular frame over
a wide range of electron energies. The measured emission times depend
drastically on the emission direction and exhibit characteristic changes along
the shape resonance of the molecule. Our approach can be routinely extended to
other electron orbitals and more complex molecules