4,598 research outputs found
Probing Short Range Nucleon Correlations in High Energy Hard Quasielastic pd Reactions
We show that the strong dependence of the amplitude for hard scattering
on the collision energy can be used to magnify the effects of short range
nucleon correlations in quasielastic scattering. Under specific
kinematical conditions the effect of initial and final state interactions can
be accounted for by rescaling the cross section calculated within the plane
wave impulse approximation. The feasibility to investigate the role of
relativistic effects in the deuteron wave function is demonstrated by comparing
the predictions of different formalisms. Binding effects due to short range
correlations in deuteron are discussed as well.Comment: 18 pages (LaTex) + 10 postscript figs (available on request
Combined premedical-medical programmes: programme structure and student outcomes at four universities
Many American universities now support combined premedical-medical programmes which shorten and integrate the education of doctors. This paper reviews combined baccalaureate-MD programmes at four institutions: Boston University, the City College of New York, The University of Michigan-Ann Arbor, and the University of Missouri-Kansas City. In comparison to most US medical schools, the combined programmes have admitted and educated larger portions of women students. In addition, some have had large proportions of graduates choosing primary-care careers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75128/1/j.1365-2923.1986.tb01053.x.pd
Dinuclear Ce(IV) Aryloxides: Highly Active Catalysts for Anhydride/Epoxide Ring-Opening Copolymerization
A library of new dinuclear CeIV complexes of the type [NEt4]2[Ce2X6(TP)(sol)2] (X = Cl, ODipp, OSiMe3; sol = py, THF), where TP represents a family of tetraphenolate ligands that control intermetallic distance, are readily made in good yields. The ligands strongly stabilize the cerium +4 oxidation state and allow the incorporation of alkylammonium cocations in an "ate"complex formulation that enables them to be used as soluble, single-component catalysts for the ring-opening copolymerization (ROCOP) of a variety of anhydrides and epoxides. High turnover frequencies (TOFs) are achieved with high ester linkage selectivity, low dispersities, and rates that are highly tunable by the intermetallic distance enforced by the TP ligand, demonstrating that a closely coupled di-CeIV unit provides excellent rates of ROCOP catalysis and that, more generally, rare-earth complexes deserve further attention as ROCOP initiators
Space Climate Manifestation in Earth Prices - from Medieval England Up to Modern Usa
In this study we continue to search for possible manifestations of space
weather influence on prices of agricultural products and consumables. We note
that the connection between solar activity and prices is based on the causal
chain that includes several nonlinear transition elements. These non-linear
elements are characterized by threshold sensitivity to external parameters and
lead to very inhomogeneous local sensitivity of the price to space weather
conditions. It is noted that "soft type" models are the most adequate for
description of this class of connections. Two main observational effects
suitable for testing causal connections of this type of sensitivity are
considered: burst-like price reactions on changes in solar activity and price
asymmetry for selected phases of the sunspot cycle. The connection, discovered
earlier for wheat prices of Medieval England, is examined in this work on the
basis of another 700-year data set of consumable prices in England. Using the
same technique as in the previous part of our work (Pistilnik and Yom Din 2004)
we show that statistical parameters of the interval distributions for price
bursts of consumables basket and for sunspot minimum states are similar one to
another, like it was reported earlier for wheat price bursts. Possible sources
of these consistencies between three different multiyear samples are discussed.
For search of possible manifestations of the "space weather - wheat market"
connection in modern time, we analyze dynamics of wheat prices in the USA in
the twentieth century. We show that the wheat prices revealed a maximum/minimum
price asymmetry consistent with the phases of the sunspot cycle. We discuss
possible explanations of this observed asymmetry, unexpected under conditions
of globalization of the modern wheat market.Comment: First International Symposium on Space Climate: Direct and Indirect
Observations of Long-Term Solar Activity, 20-23 June 2004, Oulu, Finlan
Enhanced balance associated with coordination training with stochastic resonance stimulation in subjects with functional ankle instability: an experimental trial
<p>Abstract</p> <p>Background</p> <p>Ankle sprains are common injuries that often lead to functional ankle instability (FAI), which is a pathology defined by sensations of instability at the ankle and recurrent ankle sprain injury. Poor postural stability has been associated with FAI, and sports medicine clinicians rehabilitate balance deficits to prevent ankle sprains. Subsensory electrical noise known as stochastic resonance (SR) stimulation has been used in conjunction with coordination training to improve dynamic postural instabilities associated with FAI. However, unlike static postural deficits, dynamic impairments have not been indicative of ankle sprain injury. Therefore, the purpose of this study was to examine the effects of coordination training with or without SR stimulation on static postural stability. Improving postural instabilities associated with FAI has implications for increasing ankle joint stability and decreasing recurrent ankle sprains.</p> <p>Methods</p> <p>This study was conducted in a research laboratory. Thirty subjects with FAI were randomly assigned to either a: 1) conventional coordination training group (CCT); 2) SR stimulation coordination training group (SCT); or 3) control group. Training groups performed coordination exercises for six weeks. The SCT group received SR stimulation during training, while the CCT group only performed coordination training. Single leg postural stability was measured after the completion of balance training. Static postural stability was quantified on a force plate using anterior/posterior (A/P) and medial/lateral (M/L) center-of-pressure velocity (COPvel), M/L COP standard deviation (COPsd), M/L COP maximum excursion (COPmax), and COP area (COParea).</p> <p>Results</p> <p>Treatment effects comparing posttest to pretest COP measures were highest for the SCT group. At posttest, the SCT group had reduced A/P COPvel (2.3 ± 0.4 cm/s vs. 2.7 ± 0.6 cm/s), M/L COPvel (2.6 ± 0.5 cm/s vs. 2.9 ± 0.5 cm/s), M/L COPsd (0.63 ± 0.12 cm vs. 0.73 ± 0.11 cm), M/L COPmax (1.76 ± 0.25 cm vs. 1.98 ± 0.25 cm), and COParea (0.13 ± 0.03 cm<sup>2 </sup>vs. 0.16 ± 0.04 cm<sup>2</sup>) than the pooled means of the CCT and control groups (P < 0.05).</p> <p>Conclusion</p> <p>Reduced values in COP measures indicated postural stability improvements. Thus, six weeks of coordination training with SR stimulation enhanced postural stability. Future research should examine the use of SR stimulation for decreasing recurrent ankle sprain injury in physically active individuals with FAI.</p
Case Report: Color as a Therapeutic Intervention
Peer reviewedFinal Accepted Versio
Non-perturbative dynamics of hot non-Abelian gauge fields: beyond leading log approximation
Many aspects of high-temperature gauge theories, such as the electroweak
baryon number violation rate, color conductivity, and the hard gluon damping
rate, have previously been understood only at leading logarithmic order (that
is, neglecting effects suppressed only by an inverse logarithm of the gauge
coupling). We discuss how to systematically go beyond leading logarithmic order
in the analysis of physical quantities. Specifically, we extend to
next-to-leading-log order (NLLO) the simple leading-log effective theory due to
Bodeker that describes non-perturbative color physics in hot non-Abelian
plasmas. A suitable scaling analysis is used to show that no new operators
enter the effective theory at next-to-leading-log order. However, a NLLO
calculation of the color conductivity is required, and we report the resulting
value. Our NLLO result for the color conductivity can be trivially combined
with previous numerical work by G. Moore to yield a NLLO result for the hot
electroweak baryon number violation rate.Comment: 20 pages, 1 figur
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