American newspaper book editors - a profile.

Thesis (M.S.)--Boston University N.B.: Page 38 misnumbered

Dynamical phase transition of a 1D transport process including death

Motivated by biological aspects related to fungus growth, we consider the competition of growth and corrosion. We study a modification of the totally asymmetric exclusion process, including the probabilities of injection $\alpha$ and death of the last particle $\delta$. The system presents a phase transition at $\delta_c(\alpha)$, where the average position of the last particle $$ grows as $\sqrt{t}$. For $\delta>\delta_c$, a non equilibrium stationary state exists while for $\delta<\delta_c$ the asymptotic state presents a low density and max current phases. We discuss the scaling of the density and current profiles for parallel and sequential updates.Comment: 4 pages, 5 figure

From Biology to Consciousness to Morality

Social animals are provisioned with prosocial orientations that operate to transcend self-interest. Morality, as used here, describes human versions of such orientations. We explore the evolutionary antecedents of morality in the context of emergentism, giving considerable attention to the biological traits that undergird awareness and our emergent human forms of mind. We suggest that our moral frames of mind emerge from our primate prosocial capacities, transfigured and valenced by our symbolic languages, cultures, and religions. Portions of this article were given by Deacon in a paper at the forty-ninth annual conference of IRAS, “Is Nature Enough? The Thirst for Transcendence,” Star Island, New Hampshire, 27 July-3 August 2002

Final report on interrelationships between chemical, physical and biological conditions of the waters of Las Vegas Bay of Lake Mead

This program was a status study of the interaction between Las Vegas Wash, an enriched stream, and Las Vegas Bay, a wedge shaped arm of one of the world\u27s deeper reservoirs. The program centered primarily on identification and counting of planktonic algae from several points in Las Vegas Bay. Additional work on nutrient enrichment of water samples was conducted to aid in interpretation of algal distribution related to nutrient input. Examination of a variety of physical, chemical, and biological parameters, both at many surface points in the bay, as well as in vertical profile, was also accomplished and further aided interpretation of nutrient cycling, sources of nutrient input and other limnological events commonly associated with the process of eutrophication. One copy of data is provided as an appendix to this report. Other copies are available on request. An intensive sampling program has been the core of the project. Fifteen stations were located to provide an early warning network for detection of directed movement of water bodies or strata in the bay, reliability in evaluation of surface plankton distributions, and reference points for exploitation of unanticipated opportunities. These stations were visited approximately weekly during the contract period for plankton samples to evaluate biologically-induced or biologically - responsive changes as cumulative indices of the chemical status of the system. Evaluation of results was aided by determinations of depth profiles of the standard limnological parameters: temperature, a measure of the degree of stratification or mixing of a lake, oxygen, pH and oxidation-reduction potential. Conductivity, to identify isothermal yet saline discontinuities and especially the location of the flow from Las Vegas Wash, was also measured. Colonies or unicellular plankton were counted to determine distribution versus time over the bay surface. Distribution and density, rather than productivity, was of primary interest; although evidence for growth or accumulation at given points was also obtained. Chemical analyses for principal anions and cations (such as sulfate, chloride, sodium and potassium) and major nutrients (such as phosphate) were performed in cooperation with Desert Research Institute and Environmental Protection Agency. Counts of total and coliform bacteria were made on samples from vertical profiles at various times to establish the reason for the pattern of oxygen depletion found

Flow Behavior of Asphalt Cements

The Kentucky Department of Highways in cooperation with the Bureau of Public Roads is conducting a continuing investigation of the fundamental mechanical properties of flexible pavement materials. The ultimate objective of this investigation is to gain sufficient knowledge of the fundamental mechanical behavior of these materials to support the establishment of a responsive flexible pavement design procedure. A preliminary report, issued in 1964, contained the results of the preparatory phase of this investigation. This report summarized from a theoretical point of view efforts that had been made to quantify the mechanical response of viscoelastic materials to known conditions of loading. In addition, it described the development of a rotating coaxial cylinder viscometer which was designed to measure the creep response in shear of solid or semi-solid bituminous materials. The usefulness of this viscometer was verified by testing a rubberized asphalt cement at several temperature and torque levels. It was found that rubber, when added to the asphalt cement in significant quantities, tended to increase, at the higher temperatures, the steady-state viscosity, the stiffness, the retardation time of the viscoelastic response, and the complexity of flow. The current report summarizes results of a second phase of the continuing investigation in which the preparatory efforts have been expanded to encompass the creep testing of 13 asphalt cements in a second rotating coaxial cylinder viscometer. The 13 asphalt cements were selected to represent a variety of crude sources, penetration grades, and manufacturing processes. Design and construction of the viscometer, which were accomplished as a portion of this phase, reflect the basic features of the earlier viscometer modified on the basis of the recommendations contained in the first report. In analyzing the data reported herein, efforts were made to apply existing theories for simple ideal materials such as the Newtonian liquid and the Bingham plastic whenever these theories produced results in reasonable accord with the actual data. In many instances, however, it was necessary to combine these simple theories with somewhat more complex concepts of linear visco-elasticity in order to adequately characterize the deformation properties of the materials

Quantitative resistance can lead to evolutionary changes in traits not targeted by the resistance QTLs.

This paper addresses the general concern in plant pathology that the introduction of quantitative resistance in the landscape can lead to increased pathogenicity. Hereto, we study the hypothetical case of a quantitative trait loci (QTL) acting on pathogen spore production per unit lesion area. To regain its original fitness, the pathogen can break the QTL, restoring its spore production capacity leading to an increased spore production per lesion. Or alternatively, it can increase its lesion size, also leading to an increased spore production per lesion. A data analysis shows that spore production per lesion (affected by the resistance QTL) and lesion size (not targeted by the QTL) are positively correlated traits, suggesting that a change in magnitude of a trait not targeted by the QTL (lesion size) might indirectly affect the targeted trait (spore production per lesion). Secondly, we model the effect of pathogen adaptation towards increased lesion size and analyse its consequences for spore production per lesion. The model calculations show that when the pathogen is unable to overcome the resistance associated QTL, it may compensate for its reduced fitness by indirect selection for increased pathogenicity on both the resistant and susceptible cultivar, but whereby the QTLs remain effective.Rothamsted Research receives support from the Biotechnology and Biological Sciences Research Council (BBSRC) of the United Kingdom. F v d Berg was funded by an INRA-BBSRC funded project entitled ‘Epidemiological and evolutionary models for invasion and persistence of disease’. CAG gratefully acknowledges support of a BBSRC Professional Fellowship