1,437 research outputs found
A modified technique of orthotopic transplant of the kidney in rabbits
In this study kidneys were harvested from bred-for-research cats weighing 4 to 5 kg. General principles of donor bilateral nephrectomy en bloc with aorta, vena cava, renal vessels, and ureters were followed. After the harvest the grafts were placed in lactated Ringer slush. A cuff was prepared on the renal vein over a 10 French plastic tube. The aorta was divided and left in connection with the renal artery at each side. Twenty female checkered Flemish giant rabbits weighing 4.0-6.0 kg served as recipients. After premedication with 40 mg/kg of ketamine, anesthesia was maintained with repeated doses (every 10-15 min) of a 0.1-mL mixture of 5 parts ketamine and 1 part acepromazine diluted 50% in a normal saline. Arterial pressure, CVP, blood gases, and temperature were monitored. Through a limited midline incision a native left nephrectomy was performed. The venous anastomosis was performed with a cuff technique without clamping the vena cava (which causes severe hemodynamic instability); the anastomotic time was 2-3 min. The arterial anastomosis was performed with an end-to-side aorta-to-aorta anastomosis; the anastomotic time was 5 to 7 min. There were no episodes of venous or arterial thrombosis. The donor procedure took approximately 40 min, and the backtable preparation of the graft an additional 45 to 60 min. Preparation of the recipient for the anastomosis took 15 min and the anastomotic time (warm ischemia) was 13 +/- 5 min. In this model suitable for xenograft research the duration of the surgery in the recipient has been greatly reduced because of (1) the previous backtable preparation of the graft, and (2) the cuff technique used for venous anastomosis. The present anesthesia regimen and careful hemodynamic monitoring were also important in the success of this model
Next to leading order eta production at hadron colliders
Inclusive eta production at hadron colliders is considered,based on
evaluation of eta fragmentation functions at next to leading order. Absolute
predictions at LHC and SSC are presented, including the ratio ,
together with the estimate of the theoretical uncertainty, as a possible
neutral background to the detection.Comment: 8 pages, latex, FNT/T-93/13,14 figures avilable upon reques
Transverse mass and invariant mass observables for measuring the mass of a semi-invisibly decaying heavy particle
Formulae are derived for the positions of end-points in the invariant mass
and transverse mass distributions obtained from the products of heavy states
decaying to pairs of semi-invisibly decaying lighter states. Formulae are
derived both for the special case where the two decay chains are identical and
the more general case where they are different. The formulae are tested with a
simple case study of heavy SUSY higgs particles decaying to gauginos at the
LHC.Comment: 13 pages, 8 eps figure
INCLUSIVE PARTICLE PRODUCTION IN \pbp COLLISIONS
We calculate the inclusive production of charged hadrons in \pbp collisions
to next-to-leading order (NLO) in the QCD improved parton model using a new set
of NLO fragmentation functions for charged pions and kaons. We predict
transverse-momentum distributions and compare them with experimental data from
the CERN S\pbpS Collider and the Fermilab Tevatron.Comment: the file containing the figures has been replaced: we correct a
mistake in the uuencoding procedure and we give the real Fig 4 instead of the
spurious one which was accidentally included in the previous file. the text
is unchanged
Testing the Universality of Fragmentation Functions
Using fragmentation functions for charged pions, charged kaons, and
(anti)protons recently extracted from experimental data of e^+e^- annihilation
at the Z-boson resonance and at centre-of-mass energy root(s) = 29 GeV, we
perform a global study of inclusive charged-hadron production in p anti-p,
gamma p, and gamma gamma collisions at next-to-leading order in the parton
model of quantum chromodynamics. Comparisons of our results with p anti-p data
from CERN S p anti-p S and the Fermilab Tevatron, gamma p data from DESY HERA,
and gamma gamma data from CERN LEP2 allow us to test the universality of the
fragmentation functions predicted by the factorization theorem. Furthermore, we
perform comparisons with (e^+e^-)-annihilation data from LEP2 so as to test the
scaling violations predicted by the Altarelli-Parisi evolution equations.Comment: 35 pages (Latex), 15 figures (Postscript
Higher-Order QCD Corrections to Inclusive Particle Production in p anti-p Collisions
Inclusive single-particle production cross sections have been calculated
including higher-order QCD corrections. Transverse-momentum and rapidity
distributions are presented and the scale dependence is studied. The results
are compared with experimental data from the CERN S(p anti-p)S Collider and the
Fermilab Tevatron.Comment: 28 pages, [12 uuencoded PS figures, 3 available under request].
Preprint DESY 92-13
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