Dynamics of a tunable superfluid junction

We study the population dynamics of a Bose-Einstein condensate in a double-well potential throughout the crossover from Josephson dynamics to hydrodynamics. At barriers higher than the chemical potential, we observe slow oscillations well described by a Josephson model. In the limit of low barriers, the fundamental frequency agrees with a simple hydrodynamic model, but we also observe a second, higher frequency. A full numerical simulation of the Gross-Pitaevskii equation giving the frequencies and amplitudes of the observed modes between these two limits is compared to the data and is used to understand the origin of the higher mode. Implications for trapped matter-wave interferometers are discussed.Comment: 8 pages, 7 figures; v3: Journal reference added, minor changes to tex

On Nature\u27s Prototypes: Character Design and Worldbuilding

Nature’s Prototypes is an ongoing narrative series that blends realism and fiction to create both dialectic plot structures and image sets. For substance, the series utilizes biological inquiries into fields, like ecology, pathology, and bioengineering, to imagine action-centric vignettes, where animalistic to monstrous characters become the predominant actors in a post-dystopian worldscape. Throughout these vignettes, these characters are subjected to the trials and tribulations of the catalysts and flux that are imposed upon them. In the series’ larger scope, these vignettes are sequential events within a larger timeline and an original mythos that delve into the implications and the intrigue surrounding the idea of synthetic organisms -both artificial and naturally evolved. Conceptual in nature, the series functions as a continual framework for exploring and deducing the eclectic relationships found between the aforementioned fields

Options for informal environmental management : the agricultural industry highlighted

The original article can be found at: http://www3.interscience.wiley.com Copyright John Wiley & Sons, Ltd and ERP Environment.Discussions are frequently found in the environmental press regarding the possible advantages to an organisation should they implement a formal environmental management system such as BS 7750, ISO 14001 and the EC Eco-Management and Audit Scheme (EMAS). It is also widely recognised that these formal systems, although theoretically applicable to all, are often seen by many organisations as being too unwieldy, too prescriptive, frequently too expensive and often too public. However, there are many alternative options available to organisations who do not wish to commit themselves to a formal accredited system. This paper discusses the various options currently in use for informal environmental management in agriculture with particular reference to a computerised system being developed at the University of Hertfordshire. Application examples are taken from the agricultural industry.Peer reviewe

Transverse Demagnetization Dynamics of a Unitary Fermi Gas

Understanding the quantum dynamics of strongly interacting fermions is a problem relevant to diverse forms of matter, including high-temperature superconductors, neutron stars, and quark-gluon plasma. An appealing benchmark is offered by cold atomic gases in the unitary limit of strong interactions. Here we study the dynamics of a transversely magnetized unitary Fermi gas in an inhomogeneous magnetic field. We observe the demagnetization of the gas, caused by diffusive spin transport. At low temperatures, the diffusion constant saturates to the conjectured quantum-mechanical lower bound $\simeq \hbar/m$, where $m$ is the particle mass. The development of pair correlations, indicating the transformation of the initially non-interacting gas towards a unitary spin mixture, is observed by measuring Tan's contact parameter.Comment: 8 pages, 6 figures. Accepted versio

Liquid Crystal-Solid Interface Structure at the Antiferroelectric-Ferroelectric Phase Transition

Total Internal Reflection (TIR) is used to probe the molecular organization at the surface of a tilted chiral smectic liquid crystal at temperatures in the vicinity of the bulk antiferroelectric-ferroelectric phase transition. Data are interpreted using an exact analytical solution of a real model for ferroelectric order at the surface. In the mixture T3, ferroelectric surface order is expelled with the bulk ferroelectric-antiferroelectric transition. The conditions for ferroelectric order at the surface of an antiferroelectric bulk are presented

Toward the Adoption of New Farming Systems among Farmers: A Case study of Short Rotation Woody Crops in North Carolina

This study explores the human dimensions of the broad-based adoption of Short Rotation Woody Crops (SRWCs) among farmers in North Carolina. We used an actor diagramming and tracing approach to explore factors influencing farmers’ adoption of SRWCs. Results suggest four factors strongly influence the adoption process: 1) market availability, 2) education awareness, 3) funding, and 4) social networking. Based on these results, we recommend that Extension professionals use the following education modules to prompt the adoption of SRWCs practices and potentially adopt other new farming practices: 1) ecological sustainability, 2) financial considerations, 3) harvesting, and 4) community building

Riskometer—Voting with Your Feet

As Extension professionals, we are faced with the need to educate youth and adults about risk and to assess their preference for risk; however, many find the concepts difficult to illustrate. This article lays out a simple technique that can be used to illustrate how personal attitudes toward risk change with changes in situations. Youth and adults who participate in the exercise will have a better understanding of risk and their attitudes about risk, which will lead them to make personal choices that are right for them

Defect-induced perturbations of atomic monolayers on solid surfaces

We study long-range morphological changes in atomic monolayers on solid substrates induced by different types of defects; e.g., by monoatomic steps in the surface, or by the tip of an atomic force microscope (AFM), placed at some distance above the substrate. Representing the monolayer in terms of a suitably extended Frenkel-Kontorova-type model, we calculate the defect-induced density profiles for several possible geometries. In case of an AFM tip, we also determine the extra force exerted on the tip due to the tip-induced de-homogenization of the monolayer.Comment: 4 pages, 2 figure