5,870 research outputs found

    Assessment of free-living nitrogen fixing microorganisms for commercial nitrogen fixation

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    Ammonia production by Klebsiella pneumoniae is not economical with present strains and improving nitrogen fixation to its theoretical limits in this organism is not sufficient to achieve economic viability. Because the value of both the hydrogen produced by this organism and the methane value of the carbon source required greatly exceed the value of the ammonia formed, ammonia (fixed nitrogen) should be considered the by-product. The production of hydrogen by KLEBSIELLA or other anaerobic nitrogen fixers should receive additional study, because the activity of nitrogenase offers a significant improvement in hydrogen production. The production of fixed nitrogen in the form of cell mass by Azotobacter is also uneconomical and the methane value of the carbon substrate exceeds the value of the nitrogen fixed. Parametric studies indicate that as efficiencies approach the theoretical limits the economics may become competitive. The use of nif-derepressed microorganisms, particularly blue-green algae, may have significant potential for in situ fertilization in the environment

    Barium release system

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    A chemical system is described for releasing a good yield of free barium neutral atoms and barium ions in the upper atmosphere and interplanetary space for the study of the geophysical properties of the medium. The barium is released in the vapor phase so that it can be ionized by solar radiation and also be excited to emit resonance radiation in the visible range. The ionized luminous cloud of barium becomes a visible indication of magnetic and electrical characteristics in space and allows determination of these properties over relatively large areas at a given time

    Rocket having barium release system to create ion clouds in the upper atmosphere

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    A chemical system for releasing a good yield of free barium atoms and barium ions to create ion clouds in the upper atmosphere and interplanetary space for the study of the geophysical properties of the medium is presented

    Symmetry Analysis of Multiferroic Co_3TeO_6

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    A phenomenological explanation of the magnetoelectric behavior of Co_3TeO_6 is developed. We explain the second harmonic generation data and the magnetic field induced spontaneous polarization in the magnetically ordered phase below 20K.Comment: Phys rev B Rapids, to appea

    R-modes in Neutron Stars with Crusts: Turbulent Saturation, Spin-down, and Crust Melting

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    Rossby waves (r-modes) have been suggested as a means to regulate the spin periods of young or accreting neutron stars, and also to produce observable gravitational wave radiation. R-modes involve primarily transverse, incompressive motions of the star's fluid core. However, neutron stars gain crusts early in their lives: therefore, r-modes also imply shear in the fluid beneath the crust. We examine the criterion for this shear layer to become turbulent, and derive the rate of dissipation in the turbulent regime. Unlike dissipation from a viscous boundary layer, turbulent energy loss is nonlinear in mode energy and can therefore cause the mode to saturate at amplitudes typically much less than unity. This energy loss also reappears as heat below the crust. We study the possibility of crust melting as well as its implications for the spin evolution of low-mass X-ray binaries. Lastly, we identify some universal features of the spin evolution that may have observational consequences.Comment: 12 pages, 4 figures, submitted to Ap

    IgE-Mediated Hypersensitivity Reactions to Cannabis in Laboratory Personnel

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    Background: There have been sporadic reports of hypersensitivity reactions to plants of the Cannabinaceae family (hemp and hops), but it has remained unclear whether these reactions are immunologic or nonimmunologic in nature. Objective: We examined the IgE-binding and histamine-releasing properties of hashish and marijuana extracts by CAP-FEIA and a basophil histamine release test. Methods: Two workers at a forensic laboratory suffered from nasal congestion, rbinitis, sneezing and asthmatic symptoms upon occupational contact with hashish or marijuana, which they had handled frequently for 25 and 16 years, respectively. Neither patient had a history of atopic disease. Serum was analyzed for specific IgE antibodies to hashish or marijuana extract by research prototype ImmunoCAP, and histamine release from basophils upon exposure to hashish or marijuana extracts was assessed. Results were matched to those of 4 nonatopic and 10 atopic control subjects with no known history of recreational or occupational exposure to marijuana or hashish. Results: Patient 1 had specific IgE to both hashish and marijuana (CAP class 2), and patient 2 to marijuana only (CAP class 2). Controls proved negative for specific IgE except for 2 atopic individuals with CAP class 1 to marijuana and 1 other atopic individual with CAP class 1 to hashish. Stimulation of basophils with hashish or marijuana extracts elicited histamine release from basophils of both patients and 4 atopic control subjects. Conclusions: Our results suggest an IgE-related pathomechanism for hypersensitivity reactions to marijuana or hashish. Copyright (C) 2011 S. Karger AG, Base

    Emergency supply of prescription-only medicines to patients by community pharmacists: a mixed methods evaluation incorporating patient, pharmacist and GP perspectives

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    Objective To evaluate and inform emergency supply of prescription-only medicines by community pharmacists (CPs), including how the service could form an integral component of established healthcare provision to maximise adherence. Design Mixed methods. 4 phases: prospective audit of emergency supply requests for prescribed medicines (October–November 2012 and April 2013); interviews with CPs (February–April 2013); follow-up interviews with patients (April–May 2013); interactive feedback sessions with general practice teams (October–November 2013). Setting 22 community pharmacies and 6 general practices in Northwest England. Participants 27 CPs with experience of dealing with requests for emergency supplies; 25 patients who received an emergency supply of a prescribed medicine; 58 staff at 6 general practices. Results Clinical audit in 22 pharmacies over two 4-week periods reported that 526 medicines were requested by 450 patients. Requests peaked over a bank holiday and around weekends. A significant number of supplies were made during practice opening hours. Most requests were for older patients and for medicines used in long-term conditions. Difficulty in renewing repeat medication (forgetting to order, or prescription delays) was the major reason for requests. The majority of medicines were ‘loaned’ in advance of a National Health Service (NHS) prescription. Interviews with CPs and patients indicated that continuous supply had a positive impact on medicines adherence, removing the need to access urgent care. General practice staff were surprised and concerned by the extent of emergency supply episodes. Conclusions CPs regularly provide emergency supplies to patients who run out of their repeat medication, including during practice opening hours. This may aid adherence. There is currently no feedback loop, however, to general practice. Patient care and interprofessional communication may be better served by the introduction of a formally structured and funded NHS emergency supply service from community pharmacies, with ongoing optimisation of repeat prescribing

    Symmetry Analysis for the Ruddlesden-Popper Systems, Ca3Mn2O7 and Ca3Ti2O7

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    We perform a symmetry analysis of the zero-temperature instabilities of the tetragonal phase of Ca3Mn2O7 and Ca3Ti2O7 which is stable at high temperature. We introduce order parameters to characterize each of the possible lattice distortions in order to construct a Landau free energy which elucidates the proposed group-subgroup relations for structural transitions in these systems. We include the coupling between the unstable distortion modes and the macroscopic strain tensor. We also analyze the symmetry of the dominantly antiferromagnetic ordering which allows weak ferromagnetism. We show that in this phase the weak ferromagnetic moment and the spontaneous ferroelectric polarization are coupled, so that rotating one of these ordering by applying an external electric or magnetic field one can rotate the other ordering. We discuss the number of different domains (including phase domains) which exist in each of the phases and indicate how these may be observed.Comment: 21 pages, 14 figure

    Deicing Composition

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    A deicing composition is provided. The composition includes a potassium or sodium salt of a carboxylic acid and a lithium salt of a carboxylic acid or lithium nitrate, wherein the molar ratio of lithium to potassium or lithium to sodium is from 10 percent to 80 percent

    Deicing composition

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    A deicing composition is provided. The composition includes a potassium or sodium salt of a carboxylic acid and a lithium salt of a carboxylic acid or lithium nitrate, wherein the molar ratio of lithium to potassium or lithium to sodium is from 10 percent to 80 percent
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