Beyond the Party-Group Continuum: Massachusetts Interest Groups in the 1980s

Studies in the 1960s determined that Massachusetts had strong parties and weak interest groups. In the 1970s and 1980s, as the Republican Party shrank, party competition declined, conflict with the Democratic Party grew, and interest groups gained more importance — and probably will remain important despite the Republican gains of 1990. However, group conflict and citizen mobilization, including increased use of the initiative and referendum, create a situation of interest-centered conflict rather than interest-group dominance as traditionally conceived. This article, based on a 1987 survey of state legislators and legislative aides, plus a summary of recent Massachusetts political history, assesses the relative importance of various types of groups and of particular organizations

The Transport of Water in Wet-Formed Networks of Cellulose Fibers and Powdered Superabsorbent

The wicking behavior of water into wet-formed paper strips consisting of cellulose fibers and varying proportions of powdered carboxymethyl cellulose superabsorbent is investigated and contrasted with the performance of similar composites made with the superabsorbent in fiber form. The degree of pore blocking caused by the swelling of the powdered superabsorbent is found to be significantly greater than that produced by the fibrous form, at the same superabsorbent loading

Liquid Transport in Composite Cellulose—Superabsorbent Fiber Networks

Wicking flow of water is examined in composite networks of cellulose and carboxymethyl cellulose (CMC) fibers. The rate of advance of water through paper strips and fluff pads of varying composition is reported, while dynamic electrotensiometry is used to measure the wetting and swelling characteristics of the individual cellulose and CMC fibers. Cellulose fibers swell to a small degree almost instantaneously, while CMC fibers swell to more than twice their original diameter over a period of several minutes.The Lucas-Washburn capillary model adequately describes the imbibition of a nonswelling reference liquid (n-octane) in all of the fiber networks examined. The imbibition of water, however, deviates significantly from Lucas-Washburn kinetics when CMC is present, because of the long-term swelling of the CMC fibers. The net pore restriction effected by fiber swelling is quantified by a "permeability factor," defined as the ratio of the wicking-equivalent radius in the swollen state to that in the unswollen state. A modified capillary model is developed, based on individual fiber swelling characteristics, which describes observed deviations from the Lucas-Washburn model

Dynamic Wettability Properties of Single Wood Pulp Fibers and Their Relationship to Absorbency

The Wilhelmy technique is used to measure dynamic wetting properties of single wood pulp fibers. Several different fiber types are examined, differing both in species and processing conditions. It is found that there are significant differences in water wettability of these fibers because of varying fiber surface chemistry. The compilation of a "dynamic wettability profile" for complex materials such as pulp fibers is advocated in order to characterize more fully the behavior of these materials in wetting situations. The bulk absorbency performance of three-dimensionally random pads of these fibers is found to be directly related to the initial advancing contact angles of single fibers. The measurement of single fiber wetting properties allows the separation of structural factors from surface chemical factors in considering the absorbency of a random network

Physical Properties of Hanford Transuranic Waste Sludge

Equipment that was purchased in the abbreviated year 1 of this project has been used during year 2 to study the fundamental behavior of materials that simulate the behavior of the Hanford transuranic waste sludge. Two significant results have been found, and each has been submitted for publication. Both studies found non-DLVO behavior in simulant systems. These separate but related studies were performed concurrently. It was previously shown in Rassat et al.'s report Physical and Liquid Chemical Simulant Formulations for Transuranic Wastes in Hanford Single-Shell Tanks that colloidal clays behave similarly to transuranic waste sludge (PNNL-14333, National Technical Information Service, U.S. Dept. of Commerce). Rassat et al. also discussed the pH and salt content of actual waste materials. It was shown that these materials exist at high pHs, generally above 10, and at high salt content, approximately 1.5 M from a mixture of different salts. A type of clay commonly studied, due to its uniformity, is a synthetic hectorite, Laponite. Therefore the work performed over the course of the last year was done mainly using suspensions of Laponite at high pH and involving high salt concentrations. One study was titled ''Relating Clay Rheology to Colloidal Parameters''. It has been submitted to the Journal of Colloid and INterface Science and is currently in the review process. The idea was to gain the ability to use measurable quantities to predict the flow behavior of clay systems, which should be similar to transuranic waste sludge. Leong et al. had previously shown that the yield stress of colloidal slurries of titania and alumina could be predicted, given the measurement of the accessible parameter zeta potential (Leong YK et al. J Chem Soc Faraday Trans, 19 (1993) 2473). Colloidal clays have a fundamentally different morphology and surface charge distribution than the spheroidal, uniformly charged colloids previously studied. This study was therefore performed in order to determine the applicability of the previous findings to the systems of interest. The yield stress of clay slurries was measured using the Physica MCR 300 purchased in year 1 of this project. The zeta potential of these systems was then measured using the Brookhaven Zeta PALS, also purchased in year 1. These two parameters were then plotted and compared with the Leong result. It was found that this system behaved in a non-DLVO manner. Leong found that colloidal slurry yield stress decreases with increased zeta potential which is consistent with the DLVO theory's assertion that particle attractions decrease as their electrostatic repulsion increases. Clay systems, however, show an increase in yield stress as zeta potential is increased. This is due to the nature of the charge distribution on the surface of clay particles. Clay particles are in the form of platelets

Physical Properties of Hanford Transuranic Waste

The research described herein was undertaken to provide needed physical property descriptions of the Hanford transuranic tank sludges under conditions that might exist during retrieval, treatment, packaging and transportation for disposal. The work addressed the development of a fundamental understanding of the types of systems represented by these sludge suspensions through correlation of the macroscopic rheological properties with particle interactions occurring at the colloidal scale in the various liquid media. The results of the work have advanced existing understanding of the sedimentation and aggregation properties of complex colloidal suspensions. Bench scale models were investigated with respect to their structural, colloidal and rheological properties that should be useful for the development and optimization of techniques to process the wastes at various DOE sites

Elementary simulation of tethered Brownian motion

We describe a simple numerical simulation, suitable for an undergraduate project (or graduate problem set), of the Brownian motion of a particle in a Hooke-law potential well. Understanding this physical situation is a practical necessity in many experimental contexts, for instance in single molecule biophysics; and its simulation helps the student to appreciate the dynamical character of thermal equilibrium. We show that the simulation succeeds in capturing behavior seen in experimental data on tethered particle motion.Comment: Submitted to American Journal of Physic

Inflation from D3-brane motion in the background of D5-branes

We study inflation arising from the motion of a BPS D3-brane in the background of a stack of k parallel D5-branes. There are two scalar fields in this set up-- (i) the radion field R, a real scalar field, and (ii) a complex tachyonic scalar field chi living on the world volume of the open string stretched between the D3 and D5 branes. We find that inflation is realized by the potential of the radion field, which satisfies observational constraints coming from the Cosmic Microwave Background. After the radion becomes of order the string length scale l_s, the dynamics is governed by the potential of the complex scalar field. Since this field has a standard kinematic term, reheating can be successfully realized by the mechanism of tachyonic preheating with spontaneous symmetry breaking.Comment: 10 pages, 4 figures. Minor clarifications and references added. Version to appear in Phys. Rev.

School Vouchers: Settled Questions, Continuing Disputes

Provides an assessment of the constitutional principles announced by the Court, following the June 2002 decision in the Cleveland school voucher case. Presents contrasting arguments on educational policy that address key issues about the decision

High scale impact in alignment and decoupling in two-Higgs doublet models

The two-Higgs doublet model (2HDM) provides an excellent benchmark to study physics beyond the Standard Model (SM). In this work we discuss how the behaviour of the model at high energy scales causes it to have a scalar with properties very similar to those of the SM -- which means the 2HDM can be seen to naturally favor a decoupling or alignment limit. For a type II 2HDM, we show that requiring the model to be theoretically valid up to a scale of 1 TeV, by studying the renormalization group equations (RGE) of the parameters of the model, causes a significant reduction in the allowed magnitude of the quartic couplings. This, combined with $B$-physics bounds, forces the model to be naturally decoupled. As a consequence, any non-decoupling limits in type II, like the wrong-sign scenario, are excluded. On the contrary, even with the very constraining limits for the Higgs couplings from the LHC, the type I model can deviate substantially from alignment. An RGE analysis similar to that made for type II shows, however, that requiring a single scalar to be heavier than about 500 GeV would be sufficient for the model to be decoupled. Finally, we show that not only a 2HDM where the lightest of the CP-even scalars is the 125 GeV one does not require new physics to be stable up to the Planck scale but this is also true when the heavy CP-even Higgs is the 125 GeV and the theory has no decoupling limit for the type I model.Comment: 28 pages, 19 figure