585 research outputs found
Influence of soil moisture, nitrogen fertilization, and temperature on quality and amino acid composition of Thatcher wheat, The
Includes bibliographical references (pages 227-228).The protein content of Thatcher wheat grown in the growth chamber was increased by reduced water supply, nitrogen fertilization, and higher air temperatures. Soil moisture conditions had a greater influence on protein content at higher temperatures, while the largest responses to nitrogen fertilization were obtained at the medium moisture level. Changes in sedimentation value and mixing time were associated with protein content except for plants grown at 62°F. Apparently the low temperature had an adverse effect on gluten quality. The relative distribution of 9 amino acids was significantly correlated with changes in grain protein content. Only 6 amino acids gave similar high correlations with flour protein content and sedimentation value. These differences are explained on the basis of changes in the morphology of the wheat grain and the proportion of flour proteins
Guidelines, guidelines and more guidelines: And we still do not know how to follow-up patients with breast cancer
BACKGROUND: A major challenge facing us is the provision of health care and appropriate allocation of available resources for the treatment of patients with breast cancer. This is of particular concern in the provision of follow-up care. With the increasing incidence of breast cancer and the improvements in survival which have resulted in up to 75% of patients surviving for more than five years, an increasing resource is required. However, there is controversy as to the most appropriate schedule for follow-up of these patients. This brief review has focused on the evidence-base and guidelines that currently exist in the United Kingdom for the follow-up of patients who have been treated for breast cancer. METHODS: A review of the current guidelines published in the United Kingdom for the follow-up of patients with breast cancer (National Institute for Clinical Excellence, Scottish Intercollegiate Guidelines Network, British Association of Surgical Oncology) and the randomised controlled trials evaluating the follow-up of patients with breast cancer was undertaken. RESULTS: The results have demonstrated the different follow-up protocols currently indicated in these guidelines within the same country. Furthermore, the lack of well designed, randomised controlled trials on which to base a follow-up protocol for patients with breast cancer is apparent. CONCLUSION: The evidence-base on which these guidelines have been developed is lacking. It is apparent that well designed randomised controlled trials are needed urgently if we are to understand the most appropriate and effective ways of following up patients with breast cancer
Relevance of pseudospin symmetry in proton-nucleus scattering
The manifestation of pseudospin-symmetry in proton-nucleus scattering is
discussed. Constraints on the pseudospin-symmetry violating scattering
amplitude are given which require as input cross section and polarization data,
but no measurements of the spin rotation function. Application of these
constraints to p-58Ni and p-208Pb scattering data in the laboratory energy
range of 200 MeV to 800 MeV, reveals a significant violation of the symmetry at
lower energies and a weak one at higher energies. Using a schematic model
within the Dirac phenomenology, the role of the Coulomb potential in
proton-nucleus scattering with regard to pseudospin symmetry is studied. Our
results indicate that the existence of pseudospin-symmetry in proton-nucleus
scattering is questionable in the whole energy region considered and that the
violation of this symmetry stems from the long range nature of the Coulomb
interaction.Comment: 22 pages including 9 figures, correction of 1 reference, revision of
abstract and major modification of chapter 4, Fig. 6, and Fig. 7; addition of
Fig. 8 and Fig.
Absolute Determination of the 22Na(p,g) Reaction Rate in Novae
Gamma-ray telescopes in orbit around the Earth are searching for evidence of
the elusive radionuclide 22Na produced in novae. Previously published
uncertainties in the dominant destructive reaction, 22Na(p,g)23Mg, indicated
new measurements in the proton energy range of 150 to 300 keV were needed to
constrain predictions. We have measured the resonance strengths, energies, and
branches directly and absolutely by using protons from the University of
Washington accelerator with a specially designed beamline, which included beam
rastering and cold vacuum protection of the 22Na implanted targets. The
targets, fabricated at TRIUMF-ISAC, displayed minimal degradation over a ~ 20 C
bombardment as a result of protective layers. We avoided the need to know the
stopping power, and hence the target composition, by extracting resonance
strengths from excitation functions integrated over proton energy. Our
measurements revealed that resonance strengths for E_p = 213, 288, 454, and 610
keV are stronger by factors of 2.4 to 3.2 than previously reported. Upper
limits have been placed on proposed resonances at 198-, 209-, and 232-keV. We
have re-evaluated the 22Na(p,g) reaction rate, and our measurements indicate
the resonance at 213 keV makes the most significant contribution to 22Na
destruction in novae. Hydrodynamic simulations including our rate indicate that
the expected abundance of 22Na ejecta from a classical nova is reduced by
factors between 1.5 and 2, depending on the mass of the white-dwarf star
hosting the nova explosion.Comment: 20 pages, 18 figures; shortened paper, accepted in Phys. Rev.
Probing Correlated Ground States with Microscopic Optical Model for Nucleon Scattering off Doubly-Closed-Shell Nuclei
The RPA long range correlations are known to play a significant role in
understanding the depletion of single particle-hole states observed in (e, e')
and (e, e'p) measurements. Here the Random Phase Approximation (RPA) theory,
implemented using the D1S force is considered for the specific purpose of
building correlated ground states and related one-body density matrix elements.
These may be implemented and tested in a fully microscopic optical model for NA
scattering off doubly-closed-shell nuclei. A method is presented to correct for
the correlations overcounting inherent to the RPA formalism. One-body density
matrix elements in the uncorrelated (i.e. Hartree-Fock) and correlated (i.e.
RPA) ground states are then challenged in proton scattering studies based on
the Melbourne microscopic optical model to highlight the role played by the RPA
correlations. Effects of such correlations which deplete the nuclear matter at
small radial distance (r 2 fm) and enhance its surface region, are getting
more and more sizeable as the incident energy increases. Illustrations are
given for proton scattering observables measured up to 201 MeV for the
O, Ca, Ca and Pb target nuclei. Handling the RPA
correlations systematically improves the agreement between scattering
predictions and data for energies higher than 150 MeV.Comment: 20 pages, 7 figure
Cross section and analyzing power of pol{p}p -> pn pi+ near threshold
The cross section and analyzing power of the pol{p}p -> pn pi+ reaction near
threshold are estimated in terms of data obtained from the pol{p}p -> d pi+ and
pp -> pp pi0 reactions. A simple final state interaction theory is developed
which depends weakly upon the form of the pion-production operator and includes
some Coulomb corrections. Within the uncertainties of the model and the input
data, the approach reproduces well the measured energy dependence of the total
cross section and the proton analyzing power at a fixed pion c.m. angle of
90deg, from threshold to T_p = 330 MeV. The variation of the differential cross
section with pion angle is also very encouraging.Comment: 20 pages, Latex including 4 eps figure
On the close to threshold meson production in neutron-neutron collisions
A method of measuring the close to threshold meson production in
neutron-neutron collisions is described where the momenta of the colliding
neutrons can be determined with the accuracy obtainable for the proton-proton
reaction. The technique is based on the double quasi-free nn --> nn X^0
reaction, where deuterons are used as a source of neutronsComment: 6 pages, 2 figures, to be published in Phys. Lett.
A Zero-Gravity Instrument to Study Low Velocity Collisions of Fragile Particles at Low Temperatures
We discuss the design, operation, and performance of a vacuum setup
constructed for use in zero (or reduced) gravity conditions to initiate
collisions of fragile millimeter-sized particles at low velocity and
temperature. Such particles are typically found in many astronomical settings
and in regions of planet formation. The instrument has participated in four
parabolic flight campaigns to date, operating for a total of 2.4 hours in
reduced gravity conditions and successfully recording over 300 separate
collisions of loosely packed dust aggregates and ice samples. The imparted
particle velocities achieved range from 0.03-0.28 m s^-1 and a high-speed,
high-resolution camera captures the events at 107 frames per second from two
viewing angles separated by either 48.8 or 60.0 degrees. The particles can be
stored inside the experiment vacuum chamber at temperatures of 80-300 K for
several uninterrupted hours using a built-in thermal accumulation system. The
copper structure allows cooling down to cryogenic temperatures before
commencement of the experiments. Throughout the parabolic flight campaigns,
add-ons and modifications have been made, illustrating the instrument
flexibility in the study of small particle collisions.Comment: D. M. Salter, D. Hei{\ss}elmann, G. Chaparro, G. van der Wolk, P.
Rei{\ss}aus, A. G. Borst, R. W. Dawson, E. de Kuyper, G. Drinkwater, K.
Gebauer, M. Hutcheon, H. Linnartz, F. J. Molster, B. Stoll, P. C. van der
Tuijn, H. J. Fraser, and J. Blu
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