Military identities, conventional capability and the politics of NATO standardisation at the beginning of the Second Cold War, 1970-1980

This paper uses equipment standardisation as a lens for examining power relationships and the importance of military identity in framing the development of NATO conventional capability. In the face of the Warsaw Pact's overwhelming military capacity the logic of standardisation was compelling. Standardising equipment and making military forces interoperable reduced logistics overlap, increased the tempo of operations and allowed partners to optimise manufacturing capacity. Applied carefully, standardisation would help NATO mount a successful conventional defence of Western Europe, a crucial aspect of the Alliance's flexible response strategy. In this paper we apply Actor Network Theory to standardisation discussions thereby revealing the incoherence and volatility of NATO's collective strategic thinking and the vast networks of countervailing interests on which this is based

Spin injection across magnetic/non-magnetic interfaces with finite magnetic layers

We have reconsidered the problem of spin injection across ferromagnet/non-magnetic-semiconductor (FM/NMS) and dilute-magnetic-semiconductor/non-magnetic-semiconductor interfaces, for structures with \textit{finite} magnetic layers (FM or DMS). By using appropriate physical boundary conditions, we find expressions for the resistances of these structures which are in general different from previous results in the literature. When the magnetoresistance of the contacts is negligible, we find that the spin-accumulation effect alone cannot account for the $d$ dependence observed in recent magnetoresistance data. In a limited parameter range, our formulas predict a strong $d$ dependence arising from the magnetic contacts in systems where their magnetoresistances are sizable.Comment: 6 pages, 3 eps figs. (extended version- new title + two new figures added

Advancing Use of Key Integrated Pest Management Practices in Schools

Since 2011, Oregon State University has conducted integrated pest management (IPM) training specific to public schools. School personnel receive onsite training on key IPM practices as well as associated materials. To determine which practices and materials school employees are using as a result of the program, we administered a survey to 2016 training attendees. We found that all returning attendees had been implementing practices and using materials as a result of the training. The most common practice was sealing holes to keep pests out. Additionally, the majority of respondents reported a reduction in pesticide use. Our approach may serve as a reference for Extension specialists in developing school IPM programs in other states

Full Three Dimensional Orbits For Multiple Stars on Close Approaches to the Central Supermassive Black Hole

With the advent of adaptive optics on the W. M. Keck 10 m telescope, two significant steps forward have been taken in building the case for a supermassive black hole at the center of the Milky Way and understanding the black hole's effect on its environment. Using adaptive optics and speckle imaging to study the motions of stars in the plane of sky with +-~2 mas precision over the past 7 years, we have obtained the first simultaneous orbital solution for multiple stars. Among the included stars, three are newly identified (S0-16, S0-19, S0-20). The most dramatic orbit is that of the newly identified star S0-16, which passed a mere 60 AU from the central dark mass at a velocity of 9,000 km/s in 1999. The orbital analysis results in a new central dark mass estimate of 3.6(+-0.4)x10^6(D/8kpc)^3 Mo. This dramatically strengthens the case for a black hole at the center of our Galaxy, by confining the dark matter to within a radius of 0.0003 pc or 1,000 Rsh and thereby increasing the inferred dark mass density by four orders of magnitude compared to earlier estimates. With the introduction of an adaptive-optics-fed spectrometer, we have obtained the spectra of these high-velocity stars, which suggest that they are massive (~15 Mo), young (<10 Myr) main sequence stars. This presents a major challenge to star formation theories, given the strong tidal forces that prevail over all distances reached by these stars in their current orbits and the difficulty in migrating these stars inward during their lifetime from further out where tidal forces should no longer preclude star formation.Comment: 7 pages, 5 figures (abridged abstract

Cascading Effects and Escalations in Wide Area Power Failures: A Summary for Emergency Planners

This special report is the result of a collaboration between academics and practitioners. It aims to provide a synthetic overview of the cascading effects caused by wide-area power failures, and to define the recurrent impacts and sources of escalation. It provides a reference for the training and the situational awareness of decision makers and emergency operators. The format uses bullet points and examples to facilitate reading in conditions of limited availability of time. The following topics have been developed:- ⚫ A definition of cascading effects. ⚫ An introduction for of wide area power failures (PF) policies and practices. ⚫ Illustrative examples. ⚫ A table listing cascading effects and escalations caused by wide area PF. ⚫ Resources for training and essential references for further reading

Adaptive evolution toward larger size in mammals

The notion that large body size confers some intrinsic advantage to biological species has been debated for centuries. Using a phylogenetic statistical approach that allows the rate of body size evolution to vary across a phylogeny, we find a long-term directional bias toward increasing size in the mammals. This pattern holds separately in 10 of 11 orders for which sufficient data are available and arises from a tendency for accelerated rates of evolution to produce increases, but not decreases, in size. On a branch-by-branch basis, increases in body size have been more than twice as likely as decreases, yielding what amounts to millions and millions of years of rapid and repeated increases in size away from the small ancestral mammal. These results are the first evidence, to our knowledge, from extant species that are compatible with Cope’s rule: the pattern of body size increase through time observed in the mammalian fossil record. We show that this pattern is unlikely to be explained by several nonadaptive mechanisms for increasing size and most likely represents repeated responses to new selective circumstances. By demonstrating that it is possible to uncover ancient evolutionary trends from a combination of a phylogeny and appropriate statistical models, we illustrate how data from extant species can complement paleontological accounts of evolutionary history, opening up new avenues of investigation for both

The origin of the negative torque density in disk-satellite interaction

Tidal interaction between a gaseous disk and a massive orbiting perturber is known to result in angular momentum exchange between them. Understanding astrophysical manifestations of this coupling such as gap opening by planets in protoplanetary disks or clearing of gas by binary supermassive black holes (SMBHs) embedded in accretion disks requires knowledge of the spatial distribution of the torque exerted on the disk by a perturber. Recent hydrodynamical simulations by Dong et al (2011) have shown evidence for the tidal torque density produced in a uniform disk to change sign at the radial separation of $\approx 3.2$ scale heights from the perturber's orbit, in clear conflict with the previous studies. To clarify this issue we carry out a linear calculation of the disk-satellite interaction putting special emphasis on understanding the behavior of the perturbed fluid variables in physical space. Using analytical as well as numerical methods we confirm the reality of the negative torque density phenomenon and trace its origin to the overlap of Lindblad resonances in the vicinity of the perturber's orbit - an effect not accounted for in previous studies. These results suggest that calculations of the gap and cavity opening in disks by planets and binary SMBHs should rely on more realistic torque density prescriptions than the ones used at present.Comment: 18 pages, 6 figures, accepted to Ap

The Chang-Refsdal Lens Revisited

This paper provides a complete theoretical treatment of the point-mass lens perturbed by constant external shear, often called the Chang-Refsdal lens. We show that simple invariants exist for the products of the (complex) positions of the four images, as well as moment sums of their signed magnifications. The image topographies and equations of the caustics and critical curves are also studied. We derive the fully analytic expressions for precaustics, which are the loci of non-critical points that map to the caustics under the lens mapping. They constitute boundaries of the region in the image domain that maps onto the interior of the caustics. The areas under the critical curves, caustics and precaustics are all evaluated, which enables us to calculate the mean magnification of the source within the caustics. Additionally, the exact analytic expression for the magnification distribution for the source in the triangular caustics is derived, as well as a useful approximate expression. Finally, we find that the Chang-Refsdal lens with the convergence greater than unity can exhibit third-order critical behaviour, if the reduced shear is exactly equal to \sqrt{3}/2, and that the number of images for N-point masses with non-zero constant shear cannot be greater than 5N-1.Comment: to appear in MNRAS (including 6 figures, 3 appendices; v2 - minor update with corrected typos etc.