2,865 research outputs found

    Anomalous double peak structure in Nb/Ni superconductor/ferromagnet tunneling DOS

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    We have experimentally investigated the density of states (DOS) in Nb/Ni (S/F) bilayers as a function of Ni thickness, dFd_F. Our thinnest samples show the usual DOS peak at ±Δ0\pm\Delta_0, whereas intermediate-thickness samples have an anomalous ``double-peak'' structure. For thicker samples (dF3.5d_F \geq 3.5 nm), we see an ``inverted'' DOS which has previously only been reported in superconductor/weak-ferromagnet structures. We analyze the data using the self-consistent non-linear Usadel equation and find that we are able to quantitatively fit the features at ±Δ0\pm\Delta_0 if we include a large amount of spin-orbit scattering in the model. Interestingly, we are unable to reproduce the sub-gap structure through the addition of any parameter(s). Therefore, the observed anomalous sub-gap structure represents new physics beyond that contained in the present Usadel theory.Comment: 4 pages, 3 figure

    Aplikasi Reservasi kamar pada Penginapan Timur Palembang

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    Tujuan penulisan tugas akhir ini adalah untuk merancangdan membangun aplikasi pengelolaan data reservasi kamar berbasis web pada Penginapan Timur Palembang. Aplikasi ini berfungsi untuk memenuhi kebutuhan sistem yang ada pada pemesanan kamar (reservasi). Aplikasi ini berguna untuk mempermudah dalam pencarian dan proses pencatatan transaksi dan lebih menghemat waktu. Metodologi yang digunakan dalam pengembangan aplikasi ini adalah metodologi iterasi dengan langkah-langkah: perencanaan, analisis, desain,dan penerapan. Dari hasil pembahasan tersebut maka penulis menyimpulkan bahwa dengan adanya aplikasi pengelolaan data reservasi ini, kinerja administrasi dapat meningkatkan dan meminimalkan kesalahan dalam mencatat data pelanggan, data pemesanan, data pembayaran, dan pembuatan laporan

    Aplikasi Reservasi kamar pada Penginapan Timur Palembang

    Get PDF
    Tujuan penulisan tugas akhir ini adalah untuk merancangdan membangun aplikasi pengelolaan data reservasi kamar berbasis web pada Penginapan Timur Palembang. Aplikasi ini berfungsi untuk memenuhi kebutuhan sistem yang ada pada pemesanan kamar (reservasi). Aplikasi ini berguna untuk mempermudah dalam pencarian dan proses pencatatan transaksi dan lebih menghemat waktu. Metodologi yang digunakan dalam pengembangan aplikasi ini adalah metodologi iterasi dengan langkah-langkah: perencanaan, analisis, desain,dan penerapan. Dari hasil pembahasan tersebut maka penulis menyimpulkan bahwa dengan adanya aplikasi pengelolaan data reservasi ini, kinerja administrasi dapat meningkatkan dan meminimalkan kesalahan dalam mencatat data pelanggan, data pemesanan, data pembayaran, dan pembuatan laporan

    Experiments towards quantum information with trapped Calcium ions

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    Ground state cooling and coherent manipulation of ions in an rf-(Paul) trap is the prerequisite for quantum information experiments with trapped ions. With resolved sideband cooling on the optical S1/2 - D5/2 quadrupole transition we have cooled one and two 40Ca+ ions to the ground state of vibration with up to 99.9% probability. With a novel cooling scheme utilizing electromagnetically induced transparency on the S1/2 - P1/2 manifold we have achieved simultaneous ground state cooling of two motional sidebands 1.7 MHz apart. Starting from the motional ground state we have demonstrated coherent quantum state manipulation on the S1/2 - D5/2 quadrupole transition at 729 nm. Up to 30 Rabi oscillations within 1.4 ms have been observed in the motional ground state and in the n=1 Fock state. In the linear quadrupole rf-trap with 700 kHz trap frequency along the symmetry axis (2 MHz in radial direction) the minimum ion spacing is more than 5 micron for up to 4 ions. We are able to cool two ions to the ground state in the trap and individually address the ions with laser pulses through a special optical addressing channel.Comment: Proceedings of the ICAP 2000, Firenz

    Random insertion of GFP into the cAMP-dependent protein kinase regulatory subunit from Dictyostelium discoideum

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    The green fluorescent protein (GFP) is currently being used for diverse cellular biology approaches, mainly as a protein tag or to monitor gene expression. Recently it has been shown that GFP can also be used to monitor the activation of second messenger pathways by the use of fluorescence resonance energy transfer (FRET) between two different GFP mutants fused to a Ca2+ sensor. We show here that GFP fusions can also be used to obtain information on regions essential for protein function. As FRET requires the two GFPs to be very close, N- or C-terminal fusion proteins will not generally produce FRET between two interacting proteins. In order to increase the probability of FRET, we decided to study the effect of random insertion of two GFP mutants into a protein of interest. We describe here a methodology for random insertion of GFP into the cAMP-dependent protein kinase regulatory subunit using a bacterial expression vector. The selection and analysis of 120 green fluorescent colonies revealed that the insertions were distributed throughout the R coding region. 14 R/GFP fusion proteins were partially purified and characterized for cAMP binding, fluorescence and ability to inhibit PKA catalytic activity. This study reveals that GFP insertion only moderately disturbed the overall folding of the protein or the proper folding of another domain of the protein, as tested by cAMP binding capacity. Furthermore, three R subunits out of 14, which harbour a GFP inserted in the cAMP binding site B, inhibit PKA catalytic subunit in a cAMP-dependent manner. Random insertion of GFP within the R subunit sets the path to develop two-component FRET with the C subuni

    A white-light trap for Bose-Einstein condensates

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    We propose a novel method for trapping Bose-condensed atoms using a white-light interference fringe. Confinement frequencies of tens of kHz can be achieved in conjunction with trap depths of only a few micro-K. We estimate that lifetimes on the order of 10 s can be achieved for small numbers of atoms. The tight confinement and shallow depth permit tunneling processes to be used for studying interaction effects and for applications in quantum information.Comment: 10 pages with 3 figure

    Feasibility of therapeutic pneumoperitoneum in a large animal model using a microvaporisator

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    Background: Multimodal therapy is used increasingly in advanced gastrointestinal tumors. Potential benefits of using an intraoperative adjuvant therapy during laparoscopy for cancer have been documented in animal studies. The aim of this study was to develop a device that could deliver such an intraoperative drug therapy. Methods: We developed a micropump suitable for minimally invasive surgery procedures that allowed microdroplets of therapeutic substance to be distributed into the pneumoperitoneum (CO2), creating a "therapeutic pneumoperitoneum.” A closed-loop control system regulates drug delivery according to the gas flow. In vitro, the micropump is able to aerosolize various aqueous and ethanol solutions, including cytostatic and bacteriostatic drugs and adhesionmodulating agents. The size of the microdroplets has been optimized to prevent visual artifacts. Results: The micropump was tested in an animal model (pig). The system was inserted into a 5-mm trocar. After insufflation of a 12-mm CO2 pneumoperitoneum, laparoscopic sigmoid colon resections could be performed with no special difficulties. No fog developed, and no systemrelated complication was observed. At autopsy, the active principle was distributed to all exposed peritoneal surfaces. Conclusions: As opposed to conventional peritoneal washing, therapeutic pneumoperitoneum reaches the entire peritoneal surface, allowing an optimal drug distribution. Drug diffusion into the tissues is enhanced by the intraperitoneal pressure. Precise determination of the instantaneous and total drug quantity is possible. Therefore, this drug delivery system has several advantages over conventional irrigation. Its potential domains of application are locoregional cancer therapy, prevention of port-site recurrences, immunomodulation, analgesia, peritonitis, and prevention of postoperative adhesion
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