On the Structure of a Class of Archimedean Lattice-Ordered Algebras

By a Φ-algebra A, we mean an Archimedean lattice-ordered algebra over the real field R which has an identity element 1 that is a weak order unit. The Φ-algebras constitute the class of the title. It is shown that every ф-algebra is isomorphic to an algebra of continuous functions on a compact space X into the two-point compactification of the real line R, each of which is real-valued on an (open) everywhere dense subset of X. Under more restrictive assumptions on A, ropresentations of this sort have long been known. An (incomplete) history of them is given briefly in Section 2

An investigation of the effects of urban expansion on the taxation of real property in west central Missouri

Digitized 2007 AES MoU.Includes bibliographical references (pages 55-56)

G protein beta gamma subunits synthesized in Sf9 cells. Functional characterization and the significance of prenylation of gamma

Heterotrimeric guanine nucleotide-binding regulatory proteins (G proteins) consist of a nucleotide-binding alpha subunit and a high- affinity complex of beta and gamma subunits. There is molecular heterogeneity of beta and gamma, but the significance of this diversity is poorly understood. Different G protein beta and gamma subunits have been expressed both singly and in combinations in Sf9 cells. Although expression of individual subunits is achieved in all cases, beta gamma subunit activity (support of pertussis toxin-catalyzed ADP-ribosylation of rGi alpha 1) is detected only when beta and gamma are expressed concurrently. Of the six combinations of beta gamma tested (beta 1 or beta 2 with gamma 1, gamma 2, or gamma 3), only one, beta 2 gamma 1, failed to generate a functional complex. Each of the other five complexes has been purified by subunit exchange chromatography using Go alpha-agarose as the chromatographic matrix. We have detected differences in the abilities of the purified proteins to support ADP- ribosylation of Gi alpha 1; these differences are attributable to the gamma component of the complex. When assayed for their ability to inhibit calmodulin-stimulated type-I adenylylcyclase activity or to potentiate Gs alpha-stimulated type-II adenylylcyclase, recombinant beta 1 gamma 1 and transducin beta gamma are approximately 10 and 20 times less potent, respectively, than the other complexes examined. Prenylation and/or further carboxyl-terminal processing of gamma are not required for assembly of the beta gamma subunit complex but are indispensable for high affinity interactions of beta gamma with either G protein alpha subunits or adenylylcyclases

Higher Order Terms in the Melvin-Morton Expansion of the Colored Jones Polynomial

We formulate a conjecture about the structure of `upper lines' in the expansion of the colored Jones polynomial of a knot in powers of (q-1). The Melvin-Morton conjecture states that the bottom line in this expansion is equal to the inverse Alexander polynomial of the knot. We conjecture that the upper lines are rational functions whose denominators are powers of the Alexander polynomial. We prove this conjecture for torus knots and give experimental evidence that it is also true for other types of knots.Comment: 21 pages, 1 figure, LaTe

Gravitating Fluxbranes

We consider the effect that gravity has when one tries to set up a constant background form field. We find that in analogy with the Melvin solution, where magnetic field lines self-gravitate to form a flux-tube, the self-gravity of the form field creates fluxbranes. Several exact solutions are found corresponding to different transverse spaces and world-volumes, a dilaton coupling is also considered.Comment: 14 pages, 5 figure

Disks around massive young stellar objects: are they common?

We present K-band polarimetric images of several massive young stellar objects at resolutions $\sim$ 0.1-0.5 arcsec. The polarization vectors around these sources are nearly centro-symmetric, indicating they are dominating the illumination of each field. Three out of the four sources show elongated low-polarization structures passing through the centers, suggesting the presence of polarization disks. These structures and their surrounding reflection nebulae make up bipolar outflow/disk systems, supporting the collapse/accretion scenario as their low-mass siblings. In particular, S140 IRS1 show well defined outflow cavity walls and a polarization disk which matches the direction of previously observed equatorial disk wind, thus confirming the polarization disk is actually the circumstellar disk. To date, a dozen massive protostellar objects show evidence for the existence of disks; our work add additional samples around MYSOs equivalent to early B-type stars.Comment: 9 pages, including 2 figures, 1 table, to appear on ApJ

Pair creation of black holes joined by cosmic strings

We argue that production of charged black hole pairs joined by a cosmic string in the presence of a magnetic field can be analyzed using the Ernst metric. The effect of the cosmic string is to pull the black holes towards each other, opposing to the background field. An estimation of the production rate using the Euclidean action shows that the process is suppressed as compared to the formation of black holes without strings.Comment: 7 pages, LaTeX. Minor typos corrected

Embracing change:From recalibration to radical overhaul for the field of school attendance

In a world characterized by dynamic demographic shifts, rapid technological transformations, and evolving pedagogical practices, the need for reimagining school attendance and a relationship with education has become paramount. This Research Topic, boldly titled “The Unlearning of School Attendance: Ideas for Change,” compels us to challenge conventional thinking and working in this domain. The collection of 12 articles offers compelling opportunities for change, ranging from subtle recalibrations to radical overhauls, depending on the extent to which our current ideas and methods have grown outdated. This opening article serves as a thematic guide, curating the diverse prospects for transformation found within the collection. Four themes encourage us to reconceptualize school attendance and a relationship with education, while another four themes inspire new ways of working in this realm. Furthermore, we explore the pivotal role of the International Network for School Attendance (INSA) in facilitating change, as it strives to foster relationships with education, forge alliances among interested parties, and promote interdisciplinary research. As you engage with this article and the other 12 contributions in this collection, we invite you to reflect on your current ideas and methods, embracing the call for transformative change with compassion and a strong sense of purpose. Together, we can shape a future where school attendance and engagement with learning thrive in harmony with our evolving world

Suicide prevention and mood disorders: Self-exclusion agreements for firearms as a suicide prevention strategy

Suicide involves a complex set of behaviors and emotions that lead up to actions that may be based on planning and forethought or the result of impulse. While there are a host of antecedent circumstances the presence of a mood disorder, primarily depression, is the most common factor in suicide. While management of depression is recognized as important prevention strategy in depression, the means by which suicide occurs must be a critical element of prevention. Policies that lower access to the means for suicide will decrease the fatality. Guns are associated with half of suicides and the case fatality rate of gun associated suicide is over 90% compared to 7% for all other means. This emphasizes the importance of offering strategies that limit access to guns to those at higher risk for suicide. A declaration of formal self-exclusion for access to firearms (guns and ammunition) offers the individual at greater risk for suicide to place themselves on an official list that would prevent them from purchasing lethal weapons. A person with depression, when well, might wish to enroll voluntarily to prevent themselves, when ill, from procuring a weapon to harm themselves or others. This recognizes the autonomy of the person and protects both the individual, the family, and society

Radiationless Travelling Waves In Saturable Nonlinear Schr\"odinger Lattices

The longstanding problem of moving discrete solitary waves in nonlinear Schr{\"o}dinger lattices is revisited. The context is photorefractive crystal lattices with saturable nonlinearity whose grand-canonical energy barrier vanishes for isolated coupling strength values. {\em Genuinely localised travelling waves} are computed as a function of the system parameters {\it for the first time}. The relevant solutions exist only for finite velocities.Comment: 5 pages, 4 figure