28,040 research outputs found
Sagnac interferometry based on ultra-slow polaritons in cold atomic vapors
The advantages of light and matter-wave Sagnac interferometers -- large area
on one hand and high rotational sensitivity per unit area on the other -- can
be combined utilizing ultra-slow light in cold atomic gases. While a
group-velocity reduction alone does not affect the Sagnac phase shift, the
associated momentum transfer from light to atoms generates a coherent
matter-wave component which gives rise to a substantially enhanced rotational
signal. It is shown that matter-wave sensitivity in a large-area interferometer
can be achieved if an optically dense vapor at sub-recoil temperatures is used.
Already a noticeable enhancement of the Sagnac phase shift is possible however
with much less cooling requirements.Comment: 4 pages, 3 figure
Developing a partcipatory approach to seed production and varietal selection
The performance of UK winter wheat varieties was tested under organic conditions involving farmer participation. Three breadmaking varieties (Hereward, Solstice and Xi19) and their mixture (1:1:1) were grown at 19 UK farms in 2003/04 and 2004/05. The variability of productivity on organic farms was illustrated with more variation among farm sites than among varieties. Seed health was generally high over all sites. Although the trials were successful, more time was needed at project initiation to improve farmer involvement. Some farmers expected more researcher visits, and were reticent about assessing the trials themselves. In contrast, some participants valued the variety performance data on their farms particularly when related to that of other growers. The balance between the goals of the researchers relative to the farmers needs to be defined at project initiation
Lymphotoxin is an autocrine growth factor for Epstein-Barr virus-infected B cell lines.
Because human lymphotoxin (LT) was originally isolated from a lymphoblastoid cell line, we investigated the role of this molecule in three newly established Epstein-Barr virus (EBV)-infected human B cell lines. These lines were derived from acute lymphoblastic leukemia (Z-6), myelodysplastic syndrome (Z-43), and acute myelogenous leukemia (Z-55) patients who had a prior EBV infection. Each lymphoblastoid cell line had a karyotype that was different from that of the original parent leukemic cells, and all expressed B cell, but not T cell or myeloid surface markers. In all three lines, rearranged immunoglobulin heavy chain joining region (JH) bands were found, and the presence of EBV DNA was confirmed by Southern blotting. Z-6, Z-43, and Z-55 cell lines constitutively produced 192, 48, and 78 U/ml LT, respectively, as assessed by a cytotoxicity assay and antibody neutralization. Levels of tumor necrosis factor (TNF) were undetectable. Scatchard analysis revealed that all the cell lines expressed high-affinity TNF/LT receptors with receptor densities of 4197, 1258, and 1209 sites/cell on Z-6, Z-43, and Z-55, respectively. Furthermore, labeled TNF binding could be reversed by both unlabeled TNF, as well as by LT. Studies with p60 and p80 receptor-specific antibodies revealed that the three lines expressed primarily the p80 form of the TNF receptor. When studied in a clonogenic assay, exogenous LT stimulated proliferation of all three cell lines in a dose-dependent fashion at concentrations ranging from 25 to 500 U/ml. Similar results were obtained with [3H]TdR incorporation. Monoclonal anti-LT neutralizing antibodies at concentrations of 25-500 U/ml inhibited cellular multiplication in a dose-dependent manner. It is interesting that in spite of a common receptor, TNF (1,000 U/ml) had no direct effect on Z-55 cell growth, whereas it partially reversed the stimulatory effect of exogenous LT. In addition, TNF inhibited Z-6 and Z-43 cell proliferation, and its suppressive effect was reversed by exogenous LT. Both p80 and p60 forms of soluble TNF receptors suppressed the lymphoblastoid cell line proliferation and their inhibitory effect was partially reversed by LT. Our data suggest that (a) LT is an autocrine growth factor for EBV-transformed lymphoblastoid B cell lines; and (b) anti-LT antibodies, soluble TNF/LT receptors, and TNF itself can suppress the growth of lymphoblastoid cells, probably by modulating or competing with LT.(ABSTRACT TRUNCATED AT 400 WORDS
Probing Decoherence with Electromagnetically Induced Transparency in Superconductive Quantum Circuits
Superconductive quantum circuits (SQCs) comprise quantized energy levels that
may be coupled via microwave electromagnetic fields. Described in this way, one
may draw a close analogy to atoms with internal (electronic) levels coupled by
laser light fields. In this Letter, we present a superconductive analog to
electromagnetically induced transparency (S-EIT) that utilizes SQC designs of
present day experimental consideration. We discuss how S-EIT can be used to
establish macroscopic coherence in such systems and, thereby, utilized as a
sensitive probe of decoherence.Comment: 5 pages, 3 figure
Fully differential QCD corrections to single top quark final states
A new next-to-leading order Monte Carlo program for calculation of fully
differential single top quark final states is described and first results
presented. Both the s- and t-channel contributions are included.Comment: 3 pages, 3 figures, talk presented at DPF2000, August 9-12, 2000. To
appear in International Journal of Modern Physics
Cell Size Effects on Concentrator Solar Cell Performance
The sun is an abundant power source that is clean and inexhaustible. Photovoltaic devices facilitate the collection of this energy The practice of using relatively inexpensive optics to concentrate light to reduce the amount of expensive semiconductor required has been a large driver in terrestrial application of concentrator photovoltaics (CPV). Solar cell design is critical in optimizing the device for CPV conditions. The goal of this project was to design and optimize GaAs solar cells of sizes ranging from 0.0125cm2 to 0.25cm2 for operation under a light concentration of 500 suns. The parameter of cell size was investigated in this study, as it has major impacts on solar cell perform a nce
Associated Top Quark-Higgs Boson Production at the LHC
We compute the O(alpha_s^3) inclusive cross section for the process pp ->
t-tbar-h in the Standard Model, at sqrt(s)=14 TeV. The next-to-leading order
corrections drastically reduce the renormalization and factorization scale
dependence of the Born cross section and increase the total cross section for
renormalization and factorization scales larger than m_t. These corrections
have important implications for models of new physics involving the top quark.Comment: 5 pages, 4 figures, RevTeX
Seleksi Berkorelasi pada Pertumbuhan Prasapih dan Pascasapih Kambing Peranakan Etawah Kelompok Ternak Margarini VI Desa Sungai Langka Kecamatan Gedong Tataan
Selection on growth pre weaning addition can improve the growth of livestock post weaningconcerned can boost growth. Post weaning growth due to selection on growth pre weaningexpressed as a correlated response to selection caused by a genetic correlation between the natureof the growth. The aim of this study to determine the genetic correlation between growth preweaning and post weaning Peranakan Etawah goats (PE) in the village Sungailangka, DistrictGedongtataan, Pesawaran District, Lampung Province. Research conducted the survey methodsand explore secondary data is a record growth of 40 breeding goats and 40 tai female kids,regardless of the delivery period, the Group Livestock Margarini VI. Data recording are used tocalculate the corrected weaning weight and the entire year. Parent group then used to calculategrowth pre weaning and post weaning parent. Records used to calculate kidd and the entire yearcorrected weaning weight, then used to calculate growth pre weaning and post weaning kids. Datagrowth pre weanig and post weaning parent and kidds is used to estimate the heritability of growthpre and post weaning. Genetic correlations between growth pre and post weaning analyzed withregression methods to parent kidds. Results of this study showed that the estimated geneticcorrelation between growth pre and post weaning of 0.9968 ± 0.0002 thus included in the categoryof high positive
Reconstruction of midface defect from idiopathic destructive process using Medpor implant
Importance
Reconstruction of the midface remains a challenging task for even the most experienced surgeon, with a host of reconstructive options including free tissue transfer, allografts, or prosthetic implants. Presented here is a case of idiopathic bony destruction of the right midface in a 19 year old female, creating a unique defect requiring repair.
Objective
Demonstrate a unique case of severe maxillary degeneration and discuss the associated reconstructive challenges and final repair with a prosthetic implant.
Design
Case report.
Results
The patient presented with a 7 month history of an idiopathic progressive deformity of the right cheek. Computed tomography of the paranasal sinuses revealed extensive bone loss of the right midface and orbit. The patient underwent facial reconstruction using a customized Medpor (Stryker Corp, Kalamazoo, MI) implant. At 6 month follow-up the patient and physician were both pleased with the patient's overall appearance. The patient did have some residual lower lid retraction present as well as some lateral pull at the lateral canthus outward from the orbit itself.
Conclusions
Preoperative planning for midface reconstruction requires a deep understanding of the aesthetic, functional, and supportive roles this structure holds. Computer assistance allows the creation of custom made implants, providing the reconstructive surgeon with innovative options for reconstruction with minimal morbidity to the patient. As the technology around the design and creation of the custom implants continues to improve, the role of computer assistance in reconstruction will become more prominent
Developing Decision Tree Models to Create a Predictive Blockage Likelihood Model for Real-World Wastewater Networks
To reduce the blockages occurring on wastewater networks, reducing costs, customer and environmental impact, greater levels of proactive maintenance are being conducted by water and sewerage companies. For effective prioritisation of this maintenance, an accurate model of blockage likelihood is required. This paper presents the development of a model, for provision of a blockage likelihood level and verification using unseen data, based on previous decision tree models constructed using the asset and historical incident data from the wastewater network of Dŵr Cymru Welsh Water. The model has been developed here using the geographical grouping of sewers and the application of ensemble techniques, with the results illustrating the potential benefits which can be derived from these techniques.The work has been conducted as part of a Knowledge Transfer Partnership (KTP) with funding provided by Innovate UK and Dŵr Cymru Welsh Water (DCWW), working in collaboration with the University of Exeter’s Centre for Water Systems (CWS)
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