933 research outputs found
Letter from G. Morlock to Ogden Goelet
https://digitalcommons.salve.edu/goelet-miscellaneous/1021/thumbnail.jp
Pelvic Girdle Reconstruction Based on Spinal Fusion and Ischial Screw Fixation in a Case of Aneurysmal Bone Cyst
A case of lytic lesion of the pelvis in a 23-year-old woman is presented. A biopsy led to the diagnosis aneurysmal bone cyst
(ABC). Due to the histologically very aggressive growth of the tumor, a low malignant osteosarcoma could not be excluded.
In an initial operation the tumour, affecting the sacrum, the iliac crest and the lower lumbar spine was resected. Temporary
restabilisation of the pelvic ring was achieved by a titanium plate. The histological examination of the entire tumour
confirmed the diagnosis ABC. After 6 months, the MRI showed no recurrence. The observed tilt of the spine to the operated
side on the sacral base prompted a second surgical procedure: a transpedicular fixation of L5 and L4 was connected via bent
titanium stems to the ischium, where the fixation was achieved by two screws. This construction allowed the correction of the
base angle and yielded a stable closure of the pelvic ring. The patient has now been followed for 6 years: the bone grafts have
been incorporated and, in spite of radiological signs of screw loosening in the ischium, the patient is fully rehabilitated and
free of symptoms. Pedicle screws in the lower spine can be recommended for fixation of a pelvic ring discontinuity
Strategic Activity and Financial Performance of U.S. Rural Hospitals: A National Study, 1983 to 1988
This study examines the effect of 13 strategic management activities on the financial performance of a national sample of 797 U.S. rural hospitals during the period of 1983-1988. Controlled for environment-market, geographic-region, and hospital-related variables, the results show almost no measurable effect of strategic adoption on rural hospital profitability and liquidity. Where statistically significant relationships existed, they were more often negative than positive. These findings were not expected; it was hypothesized that positive effects across a broad range of strategies would emerge, other things being equal. Discussed are possible explanations for these findings as well as their implication for a rural health policy relying on individual rural hospital strategic adaptation to environmental change.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72301/1/j.1748-0361.1994.tb00225.x.pd
Tests of Transfer Reaction Determinations of Astrophysical S-Factors
The reaction has been used to determine
asymptotic normalization coefficients for transitions to the ground and first
excited states of . The coefficients provide the normalization for
the tails of the overlap functions for and allow us
to calculate the S-factors for at astrophysical
energies. The calculated S-factors are compared to measurements and found to be
in very good agreement. This provides the first test of this indirect method to
determine astrophysical direct capture rates using transfer reactions. In
addition, our results yield S(0) for capture to the ground and first excited
states in , without the uncertainty associated with extrapolation from
higher energies.Comment: 6 pages, 2 figure
The taper corrosion pattern observed for one bi-modular stem design is related to geometry-determined taper mechanics
Bi-modular primary hip stems exhibit high revision rates owing to corrosion at the stem-neck taper, and are associated with local adverse tissue reactions. The aim of this study was to relate the wear patterns observed for one bi-modular design to its design-specific stem-neck taper geometry. Wear patterns and initial geometry of the taper junctions were determined for 27 retrieved bi-modular primary hip arthroplasty stems (Rejuvenate, Stryker Orthopaedics) using a tactile coordinate-measuring device. Regions of high-gradient wear patterns were additionally analyzed via optical and electron microscopy. The determined geometry of the taper junction revealed design-related engagement at its opening (angle mismatch), concentrated at the medial and lateral apexes (axes mismatch). A patch of retained topography on the proximal medial neck-piece taper apex was observed, surrounded by regions of high wear. On the patch, a deposit from the opposing female stem taper—containing Ti, Mo, Zr, and O—was observed. High stress concentrations were focused at the taper apexes owing to the specific geometry. A medial canting of the components may have augmented the inhomogeneous stress distributions in vivo. In the regions with high normal loads interfacial slip and consequently fretting was inhibited, which explains the observed pattern of wear
Breakup of F on Pb near the Coulomb barrier
Angular distributions of oxygen produced in the breakup of F incident
on a Pb target have been measured around the grazing angle at beam
energies of 98 and 120 MeV. The data are dominated by the proton stripping
mechanism and are well reproduced by dynamical calculations. The measured
breakup cross section is approximately a factor of 3 less than that of fusion
at 98 MeV. The influence of breakup on fusion is discussed.Comment: 7 pages, 8 figure
Measurements of branching fraction ratios and CP-asymmetries in suppressed B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^- decays
We report the first reconstruction in hadron collisions of the suppressed
decays B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^-, sensitive to the
CKM phase gamma, using data from 7 fb^-1 of integrated luminosity collected by
the CDF II detector at the Tevatron collider. We reconstruct a signal for the
B^- -> D(-> K^+ pi^-)K^- suppressed mode with a significance of 3.2 standard
deviations, and measure the ratios of the suppressed to favored branching
fractions R(K) = [22.0 \pm 8.6(stat)\pm 2.6(syst)]\times 10^-3, R^+(K) =
[42.6\pm 13.7(stat)\pm 2.8(syst)]\times 10^-3, R^-(K)= [3.8\pm 10.3(stat)\pm
2.7(syst]\times 10^-3, as well as the direct CP-violating asymmetry A(K) =
-0.82\pm 0.44(stat)\pm 0.09(syst) of this mode. Corresponding quantities for
B^- -> D(-> K^+ pi^-)pi^- decay are also reported.Comment: 8 pages, 1 figure, accepted by Phys.Rev.D Rapid Communications for
Publicatio
Observation of Exclusive Gamma Gamma Production in p pbar Collisions at sqrt{s}=1.96 TeV
We have observed exclusive \gamma\gamma production in proton-antiproton
collisions at \sqrt{s}=1.96 TeV, using data from 1.11 \pm 0.07 fb^{-1}
integrated luminosity taken by the Run II Collider Detector at Fermilab. We
selected events with two electromagnetic showers, each with transverse energy
E_T > 2.5 GeV and pseudorapidity |\eta| < 1.0, with no other particles detected
in -7.4 < \eta < +7.4. The two showers have similar E_T and azimuthal angle
separation \Delta\phi \sim \pi; 34 events have two charged particle tracks,
consistent with the QED process p \bar{p} to p + e^+e^- + \bar{p} by two-photon
exchange, while 43 events have no charged tracks. The number of these events
that are exclusive \pi^0\pi^0 is consistent with zero and is < 15 at 95% C.L.
The cross section for p\bar{p} to p+\gamma\gamma+\bar{p} with |\eta(\gamma)| <
1.0 and E_T(\gamma) > 2.5$ GeV is
2.48^{+0.40}_{-0.35}(stat)^{+0.40}_{-0.51}(syst) pb.Comment: 7 pages, 4 figure
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