Defect Specific Penetrants

The failure to detect small through-the-thickness flaws in non-metallic coatings on metallic substrates can lead to corrosion rates several orders of magnitude greater than those of the bare metal. Therefore, the detection of such defects has high priority even though presently used inspection procedures are both expensive and difficult to perform. It has recently been shown that it is possible to make a penetrant that can detect those through-thickness flaws to the exclusion of all others. These penetrants are made by adding chelating agents to a carrier fluid such as an alcohol. The chelating agent becomes fluorescent when it contacts a metal substrate. Initial work utilized the chelating agent 8-hydroxy quinoline, and is sensitive to most metals. Current work is concentrating on chelating agents that are specific to certain metals. Thus, cracks in chromium coatings or steel can be detected if they penetrate on the steel base. Work on organic and biological agents show promise

Spin Foam Models of Matter Coupled to Gravity

We construct a class of spin foam models describing matter coupled to gravity, such that the gravitational sector is described by the unitary irreducible representations of the appropriate symmetry group, while the matter sector is described by the finite-dimensional irreducible representations of that group. The corresponding spin foam amplitudes in the four-dimensional gravity case are expressed in terms of the spin network amplitudes for pentagrams with additional external and internal matter edges. We also give a quantum field theory formulation of the model, where the matter degrees of freedom are described by spin network fields carrying the indices from the appropriate group representation. In the non-topological Lorentzian gravity case, we argue that the matter representations should be appropriate SO(3) or SO(2) representations contained in a given Lorentz matter representation, depending on whether one wants to describe a massive or a massless matter field. The corresponding spin network amplitudes are given as multiple integrals of propagators which are matrix spherical functions.Comment: 30 pages, 9 figures, further remarks and references added. Version to appear in Class. Quant. Gra

Racial Equity Considerations In Safe To Sleep Messaging: Learning From The Community

In Indiana, twice as many Black infants as White infants die in their first year of life. Infants in unsafe sleep positions are more likely to die from Sudden Unexpected Infant Death (SUID). Safe to Sleep® education has led to a dramatic decrease in mortality among White infants, but over 60% of Black families do not follow Safe to Sleep® guidelines. What is the best way to share this message with Black families

Causal sites as quantum geometry

We propose a structure called a causal site to use as a setting for quantum geometry, replacing the underlying point set. The structure has an interesting categorical form, and a natural "tangent 2-bundle," analogous to the tangent bundle of a smooth manifold. Examples with reasonable finiteness conditions have an intrinsic geometry, which can approximate classical solutions to general relativity. We propose an approach to quantization of causal sites as well.Comment: 21 pages, 3 eps figures; v2: added references; to appear in JM

A feasibility test of an online intervention to prevention dating violence in emerging adults

Dating violence in emerging adults is a significant problem and few prevention programs based on the developmental needs of this age group have been developed. Our research team developed an online dating violence prevention program called WISER (Writing to Improve Self-in-Relationships) for emerging adults. The program is based on narrative therapy principles and uses structured writing techniques. A single group pre-post feasibility test of WISER was conducted with 14 college women. WISER was demonstrated to be feasible and acceptable and to show promise as an effective program to decrease dating violence in this population

Remembering the past and imagining the future in autism spectrum disorder

Recent research has revealed that episodic memory (remembering past experiences) and episodic future thinking (imagining future experiences) rely on the same underlying neuro-cognitive system. Consistent with this suggestion, individuals with autism spectrum disorder (ASD) have been shown to experience difficulties in both domains. In the present study, 18 adults with ASD and 18 typical adults performed sentence completion tasks assessing the ability to generate past and future events. Contrary to previous research findings, results demonstrated that adults with ASD performed at an equivalent level to typical adults when generating both past and future events; generating a higher number of specific events when recalling past (relative to simulating future) events, and a higher number of semantic associates when simulating future (relative to recalling past) events. Results are discussed with respect to methodological factors affecting task performance in ASD including the social nature of the research, the need to verbalise memories to the experimenter, and whether or not the specific memory request is explicit

Finite Number of States, de Sitter Space and Quantum Groups at Roots of Unity

This paper explores the use of a deformation by a root of unity as a tool to build models with a finite number of states for applications to quantum gravity. The initial motivation for this work was cosmological breaking of supersymmetry. We explain why the project was unsuccessful. What is left are some observations on supersymmetry for q-bosons, an analogy between black holes in de Sitter and properties of quantum groups, and an observation on a noncommutative quantum mechanics model with two degrees of freedom, depending on one parameter. When this parameter is positive, the spectrum has a finite number of states; when it is negative or zero, the spectrum has an infinite number of states. This exhibits a desirable feature of quantum physics in de Sitter space, albeit in a very simple, non-gravitational context.Comment: 25 pages, 5 figure

What can we learn from antique ornithology?

Ornithology has a venerable history. Worldwide, birds are both culturally important and one of the most salient reminders of the natural world, and beyond their regular appearances in folklore, literature and art they were among the first subjects of natural history from the classical world to the Renaissance. The study of birds remained a fixture of inquiry through the scientific revolution: Philosophical Transactions of the Royal Society, the oldest scientific journal still published, included ornithological method papers in its very first volume (Boyle 1666), and as scientific practice developed ornithological research kept pace. A growing interest in the diversity and systematics of birds ultimately led to the formation of dedicated ornithological societies and journals in the second half of the nineteenth century. First were the Society of German Ornithologists (Deutsche Ornithologen-Gesellschaft) in 1850 and the British Ornithologists’ Union in 1858; their respective journals ‘Journal für Ornithologie’ (now ‘Journal of Ornithology’) and ‘Ibis’ followed in 1853 and 1859. In America, the American Ornithologists’ Union was founded in 1883 with its journal ‘Auk’ beginning the same year, followed by the Wilson Ornithological Society (1886) and Cooper Ornithological Club (1893) and their journals shortly thereafter. The Royal Australasian Ornithologists’ Union (now part of BirdLife Australia) was founded in 1901, along with its journal ‘Emu’. Amazingly, all these publications are still extant, and digital versions of much of their content are now available back to their first issues. In common with other branches of science, ornithological research has exploded in recent decades, and with this plethora of new work, it is tempting to disregard the older corpus of knowledge, under the assumption that it has either been superseded or is too far removed from modern practice to be useful. However, with over 10 000 extant bird species worldwide and the avifauna of many regions still rarely studied, we would encourage the ornithological community to not overlook earlier literature. In this note, we illustrate the potential interest and value of older studies using three diverse articles published in a single journal issue 100 years ago: volume nineteen of Emu