A Biosystematic Study of \u3cem\u3eHeterotheca\u3c/em\u3e section \u3cem\u3ePityopsis\u3c/em\u3e

A biosystematic study of the section Pityopsis of the genus Heterotheca was undertaken. Cytological, morphological, chromatographic, and hybridization studies were utilized to provide a basis for taxonomic treatment of the taxa. The species were divided into two broad groups; the Heterotheca graminifolia group (H. adenolepis, H. aspera, H. graminifolia, H. microcephala var. microcephala and var. aequilifolia, and H. oligantha) and the H. pinifolia group (H. falcata, H. flexuosa, H. pinifolia, and H. ruthii) Heterotheca ruthii appears to be intermediate between the two groups and is closely related to H. oligantha. Cytology indicates the diploid species (N=9) are prominent with only H. adenolepis (both diploids and tetraploid), H. graminifolia, and H. oligantha being tetraploids (N=8). Pollen measurements were obtained showing tetraploids being significantly larger (except for H. adenolepsis). Paper chromatographs were somewhat inconclusive but generally followed the other taxonomic evidence for the section. It is thought that H. graminifolia was derived via autopolyploidy from H. microcephala. Heterotheca adenolepsis is thought to have been derived from an allopolyploid hybrid between H. aspera and H. microcephala. Heterotheca oligantha has a limited range in Florida and Alabama but appears closely related to H. graminifolia and H. ruthii. Heterotheca pinifolia, H. falcata, H. flexuosa, and H. ruthii apparently were derived from one or more primitive ancestors which migrated from an Appalachian center of origin to the Coastal Plain, became geographically separated and evolved into the four entities listed above. Heterotheca ruthii appears to be the most primitive of the four species. All are limited in rang with H. ruthii found only in the Hiwassee Gorge of East Tennessee; H. flexuosa in a few counties in Florida: H. pinifolia in a few counties in the Sand Hills of Georgia and North and South Carolina, and H. falcata in sand areas in five northeastern states. These four species have relatively few genetic barriers but are widely separated geographically

A preliminary survey of the Bryophytes of the Sapa Bog

The Sapa Bog in Ozaukee County covers 5 hectares and is the southernmost black spruce bog in Wisconsin. Sedge meadow and swamp hardwoods surround an acidic center dominated by sphagnum mosses, black spruce and tamarack. Parker (1989) surveyed the fungi and Kline (1991) surveyed the vascular plants and described the water chemistry of the area. We report a total of 56 bryophyte taxa collected in the Sapa Bog from 1989 to 1990. An asterisk indicates an apparently new report for Ozaukee County (Bowers and Freckmann, 1979). Citation of moss names follows Anderson, et. al. (1990) and Crum (1984) for Sphagnum. The liverworts nomenclature follows Conard and Redfearn (1979). Voucher specimens were deposited at the UW-Stevens Point and UWM Field Station herbaria

Epistatic Interactions Alter Dynamics of Multilocus Gene-for-Gene Coevolution

Fitness costs associated with resistance or virulence genes are thought to play a key role in determining the dynamics of gene-for-gene (GFG) host-parasite coevolution. However, the nature of interactions between fitness effects of multiple resistance or virulence genes (epistasis) has received less attention. To examine effects of the functional form of epistasis on the dynamics of GFG host-parasite coevolution we modified a classic multilocus GFG model framework. We show that the type of epistasis between virulence genes largely determines coevolutionary dynamics, and that coevolutionary fluctuations are more likely with acceleratingly costly (negative) than with linear or deceleratingly costly (positive) epistasis. Our results demonstrate that the specific forms of interaction between multiple resistance or virulence genes are a crucial determinant of host-parasite coevolutionary dynamics

The Minimal CFL-Nuclear Interface

At nuclear matter density, electrically neutral strongly interacting matter in weak equilibrium is made of neutrons, protons and electrons. At sufficiently high density, such matter is made of up, down and strange quarks in the color-flavor locked phase, with no electrons. As a function of increasing density (or, perhaps, increasing depth in a compact star) other phases may intervene between these two phases which are guaranteed to be present. The simplest possibility, however, is a single first order phase transition between CFL and nuclear matter. Such a transition, in space, could take place either through a mixed phase region or at a single sharp interface with electron-free CFL and electron-rich nuclear matter in stable contact. Here we construct a model for such an interface. It is characterized by a region of separated charge, similar to an inversion layer at a metal-insulator boundary. On the CFL side, the charged boundary layer is dominated by a condensate of negative kaons. We then consider the energetics of the mixed phase alternative. We find that the mixed phase will occur only if the nuclear-CFL surface tension is significantly smaller than dimensional analysis would indicate.Comment: 30 pages, 7 figure

Numerical Portrait of a Relativistic BCS Gapped Superfluid

We present results of numerical simulations of the 3+1 dimensional Nambu - Jona-Lasinio (NJL) model with a non-zero baryon density enforced via the introduction of a chemical potential mu not equal to 0. The triviality of the model with a number of dimensions d>=4 is dealt with by fitting low energy constants, calculated analytically in the large number of colors (Hartree) limit, to phenomenological values. Non-perturbative measurements of local order parameters for superfluidity and their related susceptibilities show that, in contrast to the 2+1 dimensional model, the ground-state at high chemical potential and low temperature is that of a traditional BCS superfluid. This conclusion is supported by the direct observation of a gap in the dispersion relation for 0.5<=(mu a)<=0.85, which at (mu a)=0.8 is found to be roughly 15% the size of the vacuum fermion mass. We also present results of an initial investigation of the stability of the BCS phase against thermal fluctuations. Finally, we discuss the effect of splitting the Fermi surfaces of the pairing partners by the introduction of a non-zero isospin chemical potential.Comment: 41 pages, 19 figures, uses axodraw.sty, v2: minor typographical correction

Bayesian learning and the psychology of rule induction

In recent years, Bayesian learning models have been applied to an increasing variety of domains. While such models have been criticized on theoretical grounds, the underlying assumptions and predictions are rarely made concrete and tested experimentally. Here, I use Frank and Tenenbaum’s (2011) Bayesian model of rule-learning as a case study to spell out the underlying assumptions, and to confront them with the empirical results Frank and Tenenbaum (2011) propose to simulate, as well as with novel experiments. While rule-learning is arguably well suited to rational Bayesian approaches, I show that their models are neither psychologically plausible nor ideal observer models. Further, I show that their central assumption is unfounded: humans do not always preferentially learn more specific rules, but, at least in some situations, those rules that happen to be more salient. Even when granting the unsupported assumptions, I show that all of the experiments modeled by Frank and Tenenbaum (2011) either contradict their models, or have a large number of more plausible interpretations. I provide an alternative account of the experimental data based on simple psychological mechanisms, and show that this account both describes the data better, and is easier to falsify. I conclude that, despite the recent surge in Bayesian models of cognitive phenomena, psychological phenomena are best understood by developing and testing psychological theories rather than models that can be fit to virtually any data

Peer expectations about outstanding competencies of men and women medical students

Men and women enrolled in a combined premedical-medical school programme were asked as they began their clinical training to rate their anticipated competence on sixteen criteria relevant to medical practice. Competence dimensions tapped scientific/technical skills, dedication/commitment, and interpersonal skills. Students then were asked to nominate one classmate whom they expected might be‘the best’in each area. Self-ratings revealed few differences among men and women. Peer nominations, however, revealed a preponderance of male nominees in ten competence areas. Women dominated nominations only in the category of sensitivity to patients. Patterns persisted when peer nominations were controlled for students’academic standing and self-ratings on parallel dimensions. The data suggest that medical school peer groups share expectations about competencies of men and women as physicians which are consistent with generalized sex stereotypes and career patterns of men and women physicians.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74843/1/1467-9566.ep11340055.pd

Protomers of Benzocaine: Solvent and Permittivity Dependence

The immediate environment of a molecule can have a profound influence on its properties. Benzocaine, the ethyl ester of para-aminobenzoic acid, which finds an application as a local anesthetic (LA), is found to adopt in its protonated form at least two populations of distinct structures in the gas phase and their relative intensities strongly depend on the properties of the solvent used in the electrospray ionization (ESI) process. Here we combine IR-vibrational spectroscopy with ion mobility-mass spectrometry (IM-MS) to yield gas-phase IR spectra of simultaneously m/z and drift-time resolved species of benzocaine. The results allow for an unambiguous identification of two protomeric species - the N- and O-protonated form. Density functional theory (DFT) calculations link these structures to the most stable solution and gas-phase structures, respectively, with the electric properties of the surrounding medium being the main determinant for the preferred protonation site. The fact that the N-protonated form of benzocaine can be found in the gas phase is owed to kinetic trapping of the solution phase structure during transfer into the experimental setup. These observations confirm earlier studies on similar molecules where N- and O-protonation has been suggested

Making Sense of Blockchain Applications:A Typology for HCI

Blockchain is an emerging infrastructural technology that is proposed to fundamentally transform the ways in which people transact, trust, collaborate, organize and identify themselves. In this paper, we construct a typology of emerging blockchain applications, consider the domains in which they are applied, and identify distinguishing features of this new technology. We argue that there is a unique role for the HCI community in linking the design and application of blockchain technology towards lived experience and the articulation of human values. In particular, we note how the accounting of transactions, a trust in immutable code and algorithms, and the leveraging of distributed crowds and publics around vast interoperable databases all relate to longstanding issues of importance for the field. We conclude by highlighting core conceptual and methodological challenges for HCI researchers beginning to work with blockchain and distributed ledger technologies

Continuity and change?: Exploring reactions to a guided self-management intervention in a randomised controlled trial for IBS with reference to prior experience of managing a long term condition

Self-care interventions are promoted as effective strategies for improving the quality of life and health outcomes for individuals with long-term health conditions. Outcome measures used in evaluations using Randomised Controlled Trials (RCTs) are not designed to consider patients' prior management strategies and experience of illness. Yet the experience of illness literature suggests that adjusting to living with chronic illness, together with broader contextual influences, are likely to be relevant to understanding responses to self-management initiatives. Using group and individual interview data we attempt to illuminate the transposition of IBS from a condition unsatisfactorily managed by medicine to one successfully managed within the life worlds of individuals. If routine embedding of complex interventions depends on the accomplishment of integration and workability in patients' everyday lives then the design and evaluation of such interventions should view participation as part of a process of continuity as well as change. Responses to formal self-management can be extended beyond psychological and other quantitatively measured outcomes. A useful addendum to trial outcomes for self-management education is an understanding of change as being inextricably linked to people's previous attempts to, and experience of, managing long-term conditions. We suggest that the benefits of understanding the prior experience of managing illness and contact with health services include the acceptability and workability of complex interventions in patients' everyday lives