Metabolomics--a new exciting field within the "omics" sciences.

keine DOI, kein abstract (Editorial!)/keg18.8.1

A Waveguide for Bose-Einstein Condensates

We report on the creation of Bose-Einstein condensates of $^{87}$Rb in a specially designed hybrid, dipole and magnetic trap. This trap naturally allows the coherent transfer of matter waves into a pure dipole potential waveguide based on a doughnut beam. Specifically, we present studies of the coherence of the ensemble in the hybrid trap and during the evolution in the waveguide by means of an autocorrelation interferometer scheme. By monitoring the expansion of the ensemble in the waveguide we observe a mean field dominated acceleration on a much longer time scale than in the free 3D expansion. Both the autocorrelation interference and the pure expansion measurements are in excellent agreement with theoretical predictions of the ensemble dynamics

Phase Fluctuations in Bose-Einstein Condensates

We demonstrate the existence of phase fluctuations in elongated Bose-Einstein Condensates (BECs) and study the dependence of those fluctuations on the system parameters. A strong dependence on temperature, atom number, and trapping geometry is observed. Phase fluctuations directly affect the coherence properties of BECs. In particular, we observe instances where the phase coherence length is significantly smaller than the condensate size. Our method of detecting phase fluctuations is based on their transformation into density modulations after ballistic expansion. An analytic theory describing this transformation is developed.Comment: 11 pages, 7 figure

Localization and Anomalous Transport in a 1-D Soft Boson Optical Lattice

We study the dynamics of Bose-Einstein condensed atoms in a 1-D optical lattice potential in a regime where the collective (Josephson) tunneling energy is comparable with the on-site interaction energy, and the number of particles per lattice site is mesoscopically large. By directly imaging the motion of atoms in the lattice, we observe an abrupt suppression of atom transport through the array for a critical ratio of these energies, consistent with quantum fluctuation induced localization. Directly below the onset of localization, the frequency of the observed superfluid transport can be explained by a phonon excitation but deviates substantially from that predicted by the hydrodynamic/Gross-Pitaevskii equations.Comment: 14 pages, 5 figure

Maximal length of trapped one-dimensional Bose-Einstein condensates

I discuss a Bogoliubov inequality for obtaining a rigorous bound on the maximal axial extension of inhomogeneous one-dimensional Bose-Einstein condensates. An explicit upper limit for the aspect ratio of a strongly elongated, harmonically trapped Thomas-Fermi condensate is derived.Comment: 6 pages; contributed paper for Quantum Fluids and Solids, Trento 2004, to appear in JLT

Adaptable-radius, time-orbiting magnetic ring trap for Bose-Einstein condensates

We theoretically investigate an adjustable-radius magnetic storage ring for laser-cooled and Bose-condensed atoms. Additionally, we discuss a novel time-dependent variant of this and other ring traps. Time-orbiting ring traps provide a high optical access method for spin-flip loss prevention near a storage ring's circular magnetic field zero. Our scalable storage ring will allow one to probe the fundamental limits of condensate Sagnac interferometry.Comment: 5 pages, 3 figures. accepted in J Phys

Agricultura e inovação: estudo sobre a viabilidade de uso do 'pó de rocha' em sistemas de produção agrícola.

O uso dos chamados remineralizadores de solo, "pó de rocha" (rochagem / ?rocks-for-crops?), é uma técnica que vem se expandindo com o passar dos anos. O trabalho visa observar o comportamento das culturas anuais de soja e milho durante três safras consecutivas, utilizando pó de rocha (remineralizador), como fonte principal da adubação verificando viabilidade econômica e técnica de uso da técnica. O projeto está sendo conduzido na Fazenda Campanário município de Itaquiraí, estado de Mato Grosso do Sul, Brasil, a partir da safra de soja 2018/2019. São três tratamentos sendo T1, utilizando adubo químico solúvel na base de plantio, T2 e T3 utilizando 12 e 6 toneladas de pó de rocha de origem basáltica respectivamente, 30 dias após o plantio. O acompanhamento da área para tomada dos dados e observações é semanal, com visitas in loco, tendo maior frequência a partir do período de implantação da cultura até sua colheita. Foram coletadas informações como: datas de plantio, emergência e colheita da cultura Tipos de manejos efetuados para o controle das pragas, doenças e plantas invasoras. A coleta do solo para análise é realizada depois da retirada de cada cultura. Análises foliares são realizadas durante o desenvolvimento da cultura.EIGEDIN 2019

Observation of Phase Fluctuations in Bose-Einstein Condensates

The occurrence of phase fluctuations due to thermal excitations in Bose-Einstein condensates (BECs) is studied for a variety of temperatures and trap geometries. We observe the statistical nature of the appearence of phase fluctuations and characterize the dependence of their average value on temperature, number of particles and the trapping potential. We find pronounced phase fluctuations for condensates in very elongated traps in a broad temperature range. The results are of great importance for the realization of BEC in quasi 1D geometries, for matter wave interferometry with BECs, as well as for coherence properties of guided atom laser beams.Comment: 4 pages, 4 figure

Homeless drug users' awareness and risk perception of peer "Take Home Naloxone" use – a qualitative study

BACKGROUND Peer use of take home naloxone has the potential to reduce drug related deaths. There appears to be a paucity of research amongst homeless drug users on the topic. This study explores the acceptability and potential risk of peer use of naloxone amongst homeless drug users. From the findings the most feasible model for future treatment provision is suggested. METHODS In depth face-to-face interviews conducted in one primary care centre and two voluntary organisation centres providing services to homeless drug users in a large UK cosmopolitan city. Interviews recorded, transcribed and analysed thematically by framework techniques. RESULTS Homeless people recognise signs of a heroin overdose and many are prepared to take responsibility to give naloxone, providing prior training and support is provided. Previous reports of the theoretical potential for abuse and malicious use may have been overplayed. CONCLUSION There is insufficient evidence to recommend providing "over the counter" take home naloxone" to UK homeless injecting drug users. However a programme of peer use of take home naloxone amongst homeless drug users could be feasible providing prior training is provided. Peer education within a health promotion framework will optimise success as current professionally led health promotion initiatives are failing to have a positive impact amongst homeless drug users

Extension of Bogoliubov theory to quasi-condensates

We present an extension of the well-known Bogoliubov theory to treat low dimensional degenerate Bose gases in the limit of weak interactions and low density fluctuations. We use a density-phase representation and show that a precise definition of the phase operator requires a space discretisation in cells of size $l$. We perform a systematic expansion of the Hamiltonian in terms of two small parameters, the relative density fluctuations inside a cell and the phase change over a cell. The resulting macroscopic observables can be computed in one, two and three dimensions with no ultraviolet or infrared divergence. Furthermore this approach exactly matches Bogoliubov's approach when there is a true condensate. We give the resulting expressions for the equation of state of the gas, the ground state energy, the first order and second order correlations functions of the field. Explicit calculations are done for homogeneous systems.Comment: 32 pages, 2 figures; typos corrected in revised versio