Propagation of QCD Color through Strongly Interacting Systems

The propagation of QCD color through atomic nuclei is studied via a new analysis using a geometric model of semi-inclusive deep inelastic scattering. The experimental data were previously published by the HERMES Collaboration and consisted of the multiplicity ratio observable (2007) and the transverse momentum broadening observable (2010). We perform a simultaneous fit of these two observables to estimate (1) the color lifetime of the quark, (2) quark energy loss, (3) the $\hat{q}$ transport coefficient, and (4) the cross section for hadronic interaction with the medium. We present preliminary results for this fit.Comment: 4 pages, 3 figures; proceedings for the Eighth International Conference on Quarks and Nuclear Physics (QNP2018), Tsukuba, Japan. https://www-conf.kek.jp/qnp2018

Parton Propagation and Fragmentation in QCD Matter

We review recent progress in the study of parton propagation, interaction and fragmentation in both cold and hot strongly interacting matter. Experimental highlights on high-energy hadron production in deep inelastic lepton-nucleus scattering, proton-nucleus and heavy-ion collisions, as well as Drell-Yan processes in hadron-nucleus collisions are presented. The existing theoretical frameworks for describing the in-medium interaction of energetic partons and the space-time evolution of their fragmentation into hadrons are discussed and confronted to experimental data. We conclude with a list of theoretical and experimental open issues, and a brief description of future relevant experiments and facilities.Comment: Invited review paper for "Rivista del Nuovo Cimento". 112 pages, 67 figures, 13 table

Deep ocean disposal of sewage sludge off Orange County, California: a research plan

Even though the discharge of sludge into the ocean via an outfall is not now permitted, this research plan has been prepared to show what could be learned with a full scale experimental sludge discharge of 150 dry tons/day by the County Sanitation Districts of Orange County into deep water (over 1000 feet). To provide a wide range of inputs and evaluation, a broad-based Research Planning Committee was established to advise the Environmental Quality Laboratory on the overall content and details of the research plan. Two meetings were held at EQL on: March 4-5, 1982: The entire Committee July 19-20, 1982: A working subgroup of the Committee The entire Committee is listed in Appendix B, with footnotes to indicate meeting attendance. Those unable to come to a meeting were asked to comment on the drafts by mail or telephone. We gratefully acknowledge the members of the Research Planning Committee for their generous help in formulating the research tasks and reviewing report drafts

Renormalization-Group Approach to Percolation Problems

The relation between the s-state Ashkin-Teller-Potts (ATP) model and the percolation problem given by Fortuin and Kasteleyn is used to formulate a renormalization-group treatment of the percolation problem. Both an ε expansion near 6 spatial dimensions and cluster approximations for the recursion relations of a triangular lattice are used. Series results for the ATP model are adapted to the percolation problem

Changes in spatiotemporal gait variables over time during a test of functional capacity after stroke

<p>Abstract</p> <p>Background</p> <p>Gait dysfunction and fatigue are common post-stroke, though it is unclear how extended walking activity, as would be performed during activities of daily living, may change over time. The purpose of this study was to examine if spatial and temporal gait variables deteriorate during an extended bout of walking in a test of functional capacity after stroke.</p> <p>Methods</p> <p>24 community dwelling, independently ambulating individuals greater than 3 months after stroke performed the Six-Minute Walk Test (6MWT). Participants walked over a pressure-sensitive mat on each pass of the 30 m course which recorded spatial and temporal parameters of gait. Mean gait speed and temporal symmetry ratio during each two-minute interval of the 6MWT were examined. Additional post hoc analyses examined the incidence of rests during the 6MWT and changes in gait speed and symmetry.</p> <p>Results</p> <p>On average, participants demonstrated a 3.4 ± 6.5 cm/s decrease in speed over time (p= 0.02). Participants who rested were also characterized by increased asymmetry in the final two minutes (p= 0.05). 30% of participants rested at some point during the test, and if a rest was taken, duration increased in the final two minutes (p= 0.001). Examination of factors which may have been associated with resting indicated that resters had poorer balance (p= 0.006) than non-resting participants.</p> <p>Conclusion</p> <p>This study supports previous findings establishing that walking performance after stroke declines over relatively short bouts of functionally-relevant ambulation. Such changes may be associated with both cardiorespiratory and muscular fatigue mechanisms that influence performance. The findings also indicate that rest duration should be routinely quantified during the 6MWT after stroke, and consequently, further research is necessary to determine how to interpret 6MWT scores when resting occurs.</p

Reduced Lean Mass in Early Alzheimer Disease and Its Association With Brain Atrophy

This is the published version. Copyright American Medical AssociationObjective: To examine body composition in individuals with early AD and without dementia and its relation to cognition and brain volume. Design: Cross-sectional case-control study. Participants: Individuals without dementia (Clinical Dementia Rating, 0; n=70) and with early-stage AD (Clinical Dementia Rating, 0.5 or 1; n=70) in the Alzheimer and Memory Program at the University of Kansas School of Medicine. Main Outcome Measures: Participants were evaluated with brain magnetic resonance imaging (MRI), neuropsychological testing, and dual-energy x-ray absorptiometry to determine whole-body fat and lean masses. Body mass index was calculated as weight in kilograms divided by height in meters squared. Results: Lean mass was reduced in persons with early AD compared with controls without dementia (F=7.73; P=.006) after controlling for sex. Whole-brain volume (=.20; P.001), white matter volume (=.19; P.001), and global cognitive performance (=.12; P=.007) were associated with lean mass (dependent variable) when controlling for age and sex. The total body fat and percentage of body fat values were not different across groups or related to cognition and brain volume. Conclusion: Loss of lean mass is accelerated in AD and is associated with brain atrophy and cognitive performance, perhaps as a direct or indirect consequence of AD pathophysiology or through shared mechanisms common to both AD and sarcopenia