Superfluid Optomechanics: Coupling of a Superfluid to a Superconducting Condensate

We investigate the low loss acoustic motion of superfluid $^4$He parametrically coupled to a very low loss, superconducting Nb, TE$_{011}$ microwave resonator, forming a gram-scale, sideband resolved, optomechanical system. We demonstrate the detection of a series of acoustic modes with quality factors as high as $7\cdot 10^6$. At higher temperatures, the lowest dissipation modes are limited by an intrinsic three phonon process. Acoustic quality factors approaching $10^{11}$ may be possible in isotopically purified samples at temperatures below 10 mK. A system of this type may be utilized to study macroscopic quantized motion and as an ultra-sensitive sensor of extremely weak displacements and forces, such as continuous gravity wave sources

Ultra-high Q Acoustic Resonance in Superfluid 4He

We report the measurement of the acoustic quality factor of a gram-scale, kilo-hertz frequency superfluid resonator, detected through the parametric coupling to a superconducting niobium microwave cavity. For temperature between 400mK and 50mK, we observe a $T^{-4}$ temperature dependence of the quality factor, consistent with a 3-phonon dissipation mechanism. We observe Q factors up to $1.4\cdot10^8$, consistent with the dissipation due to dilute $^3$He impurities, and expect that significant further improvements are possible. These experiments are relevant to exploring quantum behavior and decoherence of massive macroscopic objects, the laboratory detection of continuous wave gravitational waves from pulsars, and the probing of possible limits to physical length scales.Comment: 5 pages, 2 figure

Results from new fungus-tolerant grapevine varieties for Organic Viticulture

Two red and three white new fungus-tolerant grape varieties were tested within a period of five years. REGENT, RONDO, JOHANNITER and Gf 48-12 show a better wine quality than PINOT NOIR or SILVANER and can be recommended for Organic Viticulture as well as for the conventional viticulture to reduce copper and fungicide applications

Comparison of secondary flows predicted by a viscous code and an inviscid code with experimental data for a turning duct

A comparison of the secondary flows computed by the viscous Kreskovsky-Briley-McDonald code and the inviscid Denton code with benchmark experimental data for turning duct is presented. The viscous code is a fully parabolized space-marching Navier-Stokes solver while the inviscid code is a time-marching Euler solver. The experimental data were collected by Taylor, Whitelaw, and Yianneskis with a laser Doppler velocimeter system in a 90 deg turning duct of square cross-section. The agreement between the viscous and inviscid computations was generally very good for the streamwise primary velocity and the radial secondary velocity, except at the walls, where slip conditions were specified for the inviscid code. The agreement between both the computations and the experimental data was not as close, especially at the 60.0 deg and 77.5 deg angular positions within the duct. This disagreement was attributed to incomplete modelling of the vortex development near the suction surface

Anisotropic conductivity of disordered 2DEGs due to spin-orbit interactions

We show that the conductivity tensor of a disordered two-dimensional electron gas becomes anisotropic in the presence of both Rashba and Dresselhaus spin-orbit interactions (SOI). This anisotropy is a mesoscopic effect and vanishes with vanishing charge dephasing time. Using a diagrammatic approach including zero, one, and two-loop diagrams, we show that a consistent calculation needs to go beyond a Boltzmann equation approach. In the absence of charge dephasing and for zero frequency, a finite anisotropy \sigma_{xy} e^2/lhpf arises even for infinitesimal SOI.Comment: 6+ page

Sum rules for spin-Hall conductivity cancelation

It has been shown recently that the universal dc spin conductivity of two-dimensional electrons with a Rashba spin-orbit interaction is canceled by vertex corrections in a weak scattering regime. We prove that the zero bulk spin conductivity is an intrinsic property of the free-electron Hamiltonian and scattering is merely a tool to reveal this property in terms of the diagrammatic technique. When Zeeman energy is neglected, the zero dc conductivity persists in a magnetic field. Spin conductivity increases resonantly at the cyclotron frequency and then decays towards the universal value.Comment: 4 pages, 1 figur

Thermus aquaticus and You: Biodiversity, human health, and the interpretive challenge

Journal ArticleImagine being imprisoned for a crime you didn?t commit. How would it affect your physical, mental, and emotional health? How would it affect the health of your family and friends? Imagine your sense of helplessness when everyone who should have helped set you free? eyewitnesses, investigators, police, and attorneys?all conspired instead to build a strong case against you. After your trial and sentencing, imagine how you would feel after more than a decade behind bars for something you didn?t do

Tripping and Falling into the Future: An Eolithic Perspective

Thirty years ago, Dustin and McAvoy (1984) published an essay in Environmental Ethics titled Toward Environmental Eolithism. The article compared and contrasted two distinct orientations to environmental planning and management: the design mentality and the eolithic mentality. The authors concluded that the more popular design mentality lacked sufficient flexibility and adaptability to maximize performance, and that the more obscure eolithic mentality was a superior orientation to environmental planning and management. In this article we extend the logic of that Environmental Ethics essay to criticize a popular offshoot of the design mentality strategic planning as it is commonly conducted in the park and recreation administration, and then discuss how an eolithic perspective might complement the strategic planning process. We begin by describing the similarities between strategic planning and the design mentality as well as the shortcomings of strategic planning in a rapidly changing world. We then consider the eolithic mentality\u27s yin to strategic plannings yang. We stress the futility of planning for a future that cannot be predicted, and, consequently, how important it is for park and administrators to keep an open mind, be opportunistic,and take risks in a work world characterized by serendipity the discover of valuable but unforeseen opportunities that strategic planning, by its very nature, cannot anticipate. Finally, we conclude the article by discussing the management implications of both the design and eolithic orientations to park and recreation administration. We anchor our thinking in the management writings of Drucker (2001), Mintzberg\u27s critique of strategic planning (1994), the systems thinking of Meadows (2008) and Ackoff (1983, 1979), and the contributions of other forward-looking theorists renowned for their entrepreneurial spirit and proclivity for proactive leadership

Bat Activity Patterns and Roost Selection in Managed Forests

The recent introduction and subsequent westward spread of white-nose syndrome (WNS) has decimated hibernating bat populations in eastern North America and created an urgent need for scientists to understand basic information about bat ecology, especially during the winter season. White-nose syndrome has killed between 5 and 7 million bats and continues to spread westward from the eastern U.S. and southern Canada, primarily affecting bats during hibernation. Acoustic monitoring has been suggested as a potential surveillance tool for detecting WNS; however, baseline information must first be collected to test this technique.  We initiated a pilot project in June 2014 by deploying 2 remote acoustic monitoring stations in western Montana’s managed forests collecting baseline acoustic information. We also conducted radio telemetry to determine characteristics of roosts used by bats during the fall season. Thus far we have recorded 11 of Montana’s 15 bat species, and observed extremely high activity levels during the summer. We radio-tagged 5 bats of 3 different species (California myotis, Western small-footed myotis, Silver-haired bat) and tracked them in late October and early November. Identifying the characteristics of roost sites used during the pre-hibernation period, and the annual activity patterns determined from acoustic monitoring, begin to form the foundation for understanding basic aspects of bat ecology during the season when Montana bats will be most susceptible to WNS

Reflections on lnter-Species Parasitism: A Rejoinder to Gibson, Howard, McDonald, Wellman, and Rea

We read the reactions to our Kirrland\u27s Warbl r article with great interest, and we thank professors Gibson, Howard, McDonald, Wellman, and Rea for their thoughtful responses to it. We will continue employing the Kirtland\u27s warbler analogy in this rejoinder and organize our comments under four sub-headings: I) Birds of a Feather? 2) Feathering our own Nests? 3) Species Invasion and Succession? and 4) Bluebird of Happiness? Our intent is not so much to insist that the respondents are wrong about this matter, burro encourage the reader to ponder the implications if it turns out they are