3,393 research outputs found

    What was a mortarium used for? Organic residues and cultural change in Iron Age and Roman Britain.

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    The Romans brought the mortarium to Britain in the first century AD, and there has long been speculation on its actual purpose. Using analysis of the residues trapped in the walls of these ‘kitchen blenders’ and comparing them with Iron Age and Roman cooking pots, the authors show that it wasn't the diet that changed — just the method of preparing certain products: plants were being ground in the mortarium as well as cooked in the pot. As well as plants, the mortars contained animal fats, including dairy products. The question that remains, however, is why these natural products were being mixed together in mortaria. Were they for food, pharmaceuticals or face creams?</jats:p

    Opening Remarks: An Overview of the Problem

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    It is a pleasure to be here this morning and to give you some opening comments about what is obviously a very important issue and one that I think does require the involvement of a multitude of different persons from public policy, public health, law and other fields. As I look at the Conference program, however, I feel a little bit uneasy with my assignment since those of us in Foundations are quintessential consultants; we are not really out on the front line doing anything, but are instead providing advice, assistance, counseling, and sometimes money, to those who are out there. That description of the role of a consultant reminds me of a story that really tells you what a consultant is

    Opening Remarks: An Overview of the Problem

    Get PDF
    It is a pleasure to be here this morning and to give you some opening comments about what is obviously a very important issue and one that I think does require the involvement of a multitude of different persons from public policy, public health, law and other fields. As I look at the Conference program, however, I feel a little bit uneasy with my assignment since those of us in Foundations are quintessential consultants; we are not really out on the front line doing anything, but are instead providing advice, assistance, counseling, and sometimes money, to those who are out there. That description of the role of a consultant reminds me of a story that really tells you what a consultant is

    Tunneling control and localization for Bose-Einstein condensates in a frequency modulated optical lattice

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    The similarity between matter waves in periodic potential and solid-state physics processes has triggered the interest in quantum simulation using Bose-Fermi ultracold gases in optical lattices. The present work evidences the similarity between electrons moving under the application of oscillating electromagnetic fields and matter waves experiencing an optical lattice modulated by a frequency difference, equivalent to a spatially shaken periodic potential. We demonstrate that the tunneling properties of a Bose-Einstein condensate in shaken periodic potentials can be precisely controlled. We take additional crucial steps towards future applications of this method by proving that the strong shaking of the optical lattice preserves the coherence of the matter wavefunction and that the shaking parameters can be changed adiabatically, even in the presence of interactions. We induce reversibly the quantum phase transition to the Mott insulator in a driven periodic potential.Comment: Laser Physics (in press

    Maine EPSCoR End-to-End Connectivity for Sustainability Science Collaboration

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    This NSF EPSCoR C2 project allowed Maine EPSCoR to continue the state’s momentum to enhance the connectivity of the state’s research, higher education, and K-12 institutions through Maine’s Research and Education Network (MaineREN). Over the last few years, multi-million dollar investments have built networking and computing power at the state level, including: 1) the installation of 1,100 miles of middle-mile fiber optic cable; 2) investments in shared computing resources for high performance computing and cloud computing; 3) the Maine School and Library Network; 4) the Maine Learning Technology Initiative (grade 6-12 laptops); and 5) investments in high-performance visualization and videoconferencing. This C2 project allowed Maine EPSCoR to address the cyberinfrastructure gaps at the seven campuses of the University of Maine System that had still been preventing the delivery of true end-to-end connectivity between Maine’s researchers and the new advanced networking services provided over MaineREN. The research and education focus that was enabled by this C2 project is the Maine EPSCoR Sustainability Science Initiative (SSI) Rll Track 1, with the goal of providing SSI researchers and students at the seven campuses of the University of Maine System true end-to-end connectivity. Cyberinfrastructure is an important key to helping SSI to advance their sustainability science objectives to: 1) examine interactions between social and ecological systems (SES) as landscapes change in response to urbanization, forest management, and climate variability; 2) investigate how such SES knowledge affects, and is influenced by, the actions and decisions of diverse stakeholders, with a goal of strengthening connections between knowledge and action; 3) evaluate the factors that facilitate and impede interdisciplinary collaboration, with a goal of identifying and implementing individual and institutional best practices that are needed to support successful interdisciplinary research programs in sustainability science. In particular, the C2 connectivity improvements that are now in place will support the Track 1 SSI research agenda by addressing various data management, visualization, and virtual proximity challenges that were present. Except for a small amount of support towards the AAAS review, all of the C2 budget was allocated for the capital cyberinfrastructure improvements, with the goal of enabling the effectiveness of the research and education activities of the SSI Track 1 project. This then means that there is a high degree of leveraging and synergy between the two projects, and that the personnel participation, research, diversity, and workforce development activities were supported from a variety of other sources including SSI Track 1, state funds, university funds, and UMaine System funds (and therefore are not a direct part of this award). While somewhat confusing for reporting purposes, this high degree of leveraging resulted in a tightly integrated and effective manner of furthering Maine’s research and education capacity in Sustainability Science. The implementation and administration of all three NSF EPSCoR projects (Track 1, 2, C2) has been through the Maine EPSCoR office at the University of Maine, which allowed for effective coordination and leveraging of resources and investments for the maximum benefit to Maine researchers

    Maine EPSCoR End-to-End Connectivity for Sustainability Science Collaboration

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    Project DescriptionThis RII C2 proposal from Maine (ME) EPSCoR is focused on addressing last-mile bottlenecks at seven campuses of the University of Maine System. Maine\u27s Research and Education Network, MaineREN, delivers high performance inter-campus fiber connectivity to public and private institutions across the state, but the intra-campus networking has lacked the same investment by the state.The proposed improvements include:- Rewiring eight buildings at the University of Maine Orono Campus (UMaine) with Cat-6 cable, increasing end-to-end performance to 10 Gbps.- Upgrading the fiber backbone between the two University of Southern Maine (USM) campuses, one in Portland and one in Gorham, 12 miles apart. In addition, upgrades will be done for the buildings housing the ME RII Track-1 researchers, including the Law Building, Library, Bailey Hall, and the buildings that make up the fiber core for the Portland campus. - Upgrades to edge routers to connect to the MaineREN backbone for UMaine Augusta (UMA), UMaine Farmington (UMF), UMaine Fort Kent (UMFK), UMaine Machias (UMM), and UMaine Presque Isle (UMPI). Intellectual MeritThe proposed upgrades in network connections will greatly improve the networking capacity available to the University of Maine system and enable researchers to take advantage of state-wide upgrades with improved end-to-end performance. The proposed RII C2 connectivity improvements will support the Maine RII Track-1 Sustainability Science Initiative (SSI) by increasing bandwidth availability for the SSI data management and visualization approaches. SSI is advancing the emerging field of sustainability science in three integrative ways: 1) examining interactions between social and ecological systems (SES) as landscapes change in response to urbanization, forest management, and climate variability; 2) investigating how much SES knowledge affects, and is influenced by, the actions and decision of stakeholders, with a goal of strengthening connections between knowledge and actions; 3) evaluating the factors that facilitate and impede interdisciplinary collaboration, with a goal of identifying and implementing individual and institutional best practices that are needed to support successful interdisciplinary research programs in sustainability science.Broader ImpactsBy filling in relatively small gaps in the infrastructure, Maine will be able to make very large gains in the effectiveness of the state\u27s cyberinfrastructure (CI) that will allow researchers to fully utilize investments to improve research effectiveness, promote collaboration, improve K-12 interaction, and develop the future workforce of the state. The networking upgrades will support the 300 researchers, students, and stakeholders that are part of the SSI collaboration over 17 different disciplinary fields. The SSI activities have the potential to increase Maine\u27s research capacity and competitiveness and grow Maine\u27s green innovation economy. The proposed project will leverage the RII Track-1 programs for broader impacts

    New Results from NA49

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    We present recent results of the SPS experiment NA49 on production of strange particles and event-by-event fluctuations of mean ptp_t and of charged particle ratios in central Pb+Pb collisions at various beam energies (40, 80, 158 AGeV) as well as in different collisions at 158 AGeV, going from p+p over light-ion collisions to peripheral and central Pb+Pb.Comment: 5 pages, 6 figures (in eps) talk given at XXXI International Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong China URL http://ismd31.ccnu.edu.cn

    Ground state energy of a homogeneous Bose-Einstein condensate beyond Bogoliubov

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    The standard calculations of the ground-state energy of a homogeneous Bose gas rely on approximations which are physically reasonable but difficult to control. Lieb and Yngvason [Phys. Rev. Lett. 80, 2504 (1998)] have proved rigorously that the commonly accepted leading order term of the ground state energy is correct in the zero-density-limit. Here, strong indications are given that also the next to leading term is correct. It is shown that the first terms obtained in a perturbative treatment provide contributions which are lost in the Bogoliubov approach.Comment: 6 pages, accepted for publication in Europhys. Lett. http://www.epletters.ch

    Interaction-dependent photon-assisted tunneling in optical lattices: a quantum simulator of strongly-correlated electrons and dynamical gauge fields

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    We introduce a scheme that combines photon-assisted tunneling by a moving optical lattice with strong Hubbard interactions, and allows for the quantum simulation of paradigmatic quantum many-body models. We show that, in a certain regime, this quantum simulator yields an effective Hubbard Hamiltonian with tunable bond-charge interactions, a model studied in the context of strongly-correlated electrons. In a different regime, we show how to exploit a correlated destruction of tunneling to explore Nagaoka ferromagnetism at finite Hubbard repulsion. By changing the photon-assisted tunneling parameters, we can also obtain a t-J model with independently controllable tunneling t, super-exchange interaction J, and even a Heisenberg-Ising anisotropy. Hence, the full phase diagram of this paradigmatic model becomes accessible to cold-atom experiments, departing from the region t _ J allowed by standard single-band Hubbard Hamiltonians in the strong-repulsion limit. We finally show that, by generalizing the photon-assisted tunneling scheme, the quantum simulator yields models of dynamical Gauge fields, where atoms of a given electronic state dress the tunneling of the atoms with a different internal state, leading to Peierls phases that mimic a dynamical magnetic field
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