Phenomenological Constraints on the Transport Properties of QCD Matter with Data-Driven Model Averaging.

Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.

Transverse velocity dependence of the proton-antiproton ratio as a signature of the QCD critical point.

The presence of a critical point in the QCD phase diagram can deform the trajectories describing the evolution of the expanding fireball in the mu_B-T phase diagram. If the average emission time of hadrons is a function of transverse velocity, as microscopic simulations of the hadronic freeze-out dynamics suggest, the deformation of the hydrodynamic trajectories will change the transverse velocity (beta_T) dependence of the proton-antiproton ratio when the fireball passes in the vicinity of the critical point. An unusual beta_T dependence of the [over]p/p ratio in a narrow beam energy window would thus signal the presence of the critical point.

Longitudinal broadening of quenched jets in turbulent color fields.

The nearside distribution of particles at intermediate transverse momentum, associated with a high momentum trigger hadron produced in a high energy heavy-ion collision, is broadened in rapidity compared with the jet cone. This broadened distribution is thought to contain the energy lost by the progenitor parton of the trigger hadron. We show that the broadening can be explained as the final-state deflection of the gluons radiated from the hard parton inside the medium by soft, transversely oriented, turbulent color fields that arise in the presence of plasma instabilities. The magnitude of the effect is found to grow with medium size and density and diminish with increasing energy of the associated hadron.

Anomalous viscosity of an expanding quark-gluon plasma.

We argue that an expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated color fields. We derive an expression for the anomalous viscosity in the turbulent plasma domain and apply it to the hydrodynamic expansion phase, when the quark-gluon plasma is near equilibrium. The anomalous viscosity dominates over the collisional viscosity for weak coupling and not too late times. This effect may provide an explanation for the apparent "nearly perfect" liquidity of the matter produced in nuclear collisions at the Relativistic Heavy Ion Collider without the assumption that it is a strongly coupled state.

Correlated emission of hadrons from recombination of correlated partons.

We discuss different sources of hadron correlations in relativistic heavy ion collisions. We show that correlations among partons in a quasithermal medium can lead to the correlated emission of hadrons by quark recombination and argue that this mechanism offers a plausible explanation for the dihadron correlations in the few GeV/c momentum range observed in Au+Au collisions at the BNL Relativistic Heavy Ion Collider.

Hadronization in heavy-ion collisions: recombination and fragmentation of partons.

We argue that the emission of hadrons with transverse momentum up to about 5 GeV/c in central relativistic heavy ion collisions is dominated by recombination, rather than fragmentation of partons. This mechanism provides a natural explanation for the observed constant baryon-to-meson ratio of about one and the apparent lack of a nuclear suppression of the baryon yield in this momentum range. Fragmentation becomes dominant at higher transverse momentum, but the transition point is delayed by the energy loss of fast partons in dense matter.

Overpopulation of Omega; in pp collisions: a way to distinguish statistical hadronization from string dynamics.

The Omega/Omega ratio originating from string decays is predicted to be larger than unity in proton-proton interactions at SPS energies ( E(lab) = 160 GeV). The antiomega dominance increases with decreasing beam energy. This surprising behavior is caused by the combinatorics of quark-antiquark production in small and low-mass strings. Since this behavior is not found in a statistical description of hadron production in proton-proton collisions, it may serve as a key observable to probe the hadronization mechanism in such collisions.

Pion interferometry at RHIC: porobing a thermalized quark-gluon plasma?

We calculate the Gaussian radius parameters of the pion-emitting source in high-energy heavy-ion collisions, assuming a first-order phase transition from a thermalized quark-gluon plasma (QGP) to a gas of hadrons. Such a model leads to a very long-lived dissipative hadronic rescattering phase which dominates the properties of the two-pion correlation functions. The radii are found to depend only weakly on the thermalization time tau(i), the critical temperature Tc (and thus the latent heat), and the specific entropy of the QGP. The model calculations suggest a rapid increase of R(out)/R(side) as a function of KT if a thermalized QGP were formed.

Gerontology education in transition: considering disciplinary and paradigmatic evolution.

The disciplinary status of gerontology has long been the subject of much debate, but recent changes in higher education suggest the early development of a more integrated, interdisciplinary approach to gerontological education and research. We assert that gerontology is currently a multidisciplinary field of inquiry, but at selected schools it is moving toward an interdisciplinary field and may ultimately evolve into a new discipline. The risks and benefits attendant with this disciplinary evolution are reviewed in light of the historical development of other disciplines. Factors that may accelerate the development of interdisciplinary gerontology education include paradigm development in gerontology and the success of gerontology PhD programs, especially the placement of their graduates.

Microbial barrier assessment of Tyvek stopper packaging for rubber closures.

Two types of Tyvek and high density polyethylene or polypropylene packaging used for sterilization of rubber closures were evaluated for Microbial Barrier properties. The packaging evaluated was "Ready to Sterilize" (1) stoppers and a second test package (Test 2) which was designated as appropriate for a clean room, filled with washed and siliconized stoppers and then heat sealed. Each type of packaging was subjected to three different sterilization temperatures (125 degrees C, 128 degrees C and 131 degrees C) in a production sterilizer (15-18 psi). Following sterilization, a microbial barrier assessment was performed, using Bacillus subtilis niger (ATCC 9372), to determine whether the packaging could maintain a sterile barrier following sterilization. Results of the testing indicated that a microbial barrier was maintained for products in "Ready to Sterilize" packages at 125 degrees C and 128 degrees C. For products sterilized in the Test 2 container a microbial barrier could not be maintained at 128 degrees C, and no further testing was performed. Following sterilization at 131 degrees C physical defects were noted for the "Ready to Sterilize" bag and a microbial barrier could not be maintained.

An overview of work, retirement, and pensions in Japan.

Work to retirement in Japan is a sequential transition for the most part, and Japan permits mandatory retirement by firms at age 60. But many older people work beyond the age of 60, many more than in other industrialized countries. A number of hypotheses are examined, having to do with pensions, health, opportunity, interest in working, cultural attitudes (including the concept of ikigai), and public policy initiatives (such as employment policy and the Silver Human Resource Centers). Japan's cultural attitudes and existing policies appear to have set Japan on a unique course in considering the aging of its population. To what extent should other nations emulate Japan?

An older-worker employment model: Japan's Silver Human Resource Centers.

Over the past 20 years, a unique model of publicly assisted industries has developed in Japan, which contracts for services provided by retirees. Jobs for retirees are part-time and temporary in nature and, for the most part, are designed to assist in expanding community-based services. The program, known as the Silver Human Resource Centers, has expanded nationwide and reflects a novel approach to the productive engagement of retirees in society that may be replicable in other industrialized nations.

International perspectives on aging policy: A review essay of three recent volumes.

Only in the very broadest and most abstract sense do these three volumes reflect on similar issues in aging in social policy - that is, the changing context of the responsibilities of the family and state toward the aged. Within two of these books the prevailing wisdom is that the state in most cases will be taking on fewer responsibilities with families assuming more. In certain societies and cultures, little in the way of a role has been associated with the state historically. Care for the elderly has been the responsibility of the family and/or community, and despite changes in the economy and society, human exchanges have remained unaltered. In other societies, change has been more rapid, leaving elders without adequate support or nurturance. And, in largely industrial and Western societies, the state may be relinquishing its roles, leaving families stretching to cover the gaps. Only Schulz, Borowski, and Crown provide carefully reasoned economic arguments regarding the capacity of the state to provide continued financial security to the aged in the future. But future economic security for the elderly does not respond to the broader issues of the responsibility for caring and social support that the other authors have alluded may be eroding from those states that currently provide such services. Admittedly, the direction in all the nations discussed and in each of the volumes is to a smaller role for government and an increased role for families.Each of the three books reviewed is truly international in authorship and perspective. Sensitive to the concern that Bleddyn Davies from the University of Kent at Canterbury articulates as the dominance of an American perspective in aging and social policy (1989), the authors and editors have been global and multinational in their work. In particular,An Aging World has attracted authors from nations throughout the world with few using examples or comparisons to the United States.It has been difficult to review three works that are so different and span so much content. The depth of material, the detail, and the many issues raised inAn Aging World in itself are difficult to summarize. Nevertheless, it is the specifics and the details that make these works so interesting to read.