425 research outputs found

    Modeling The Complex Land Administration in Brazil

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    Land administration is one of the pillars of economic development and poverty reduction. Land registration and cadastres make up an important part of land administration. In Brazil, recent initiatives attempt to build an efficient land administration to overcome its deficiencies built from a history of disorderly occupation and with many specificities of a colonial past. The objective of this paper is to present the land registration process in urban areas in Brazil using modeling of land administration. The purpose is to present in a model the procedures for three scenarios of the registration and transfer of urban properties: 1. Procedures for transfer a formally registered; 2. Procedures for registration of a semi-formal property (individual proceeding); and 3. Procedures for the registration of an informal settlement (collective proceeding). From the models it was possible to visualize the complexity of the procedures of registration and transfer of a property in the urban area. The procedures usually have many steps, many actors involved, it requires a lot of time and it has high costs. In addition, the procedures show the absence of an urban cadastre that supports land registration. In conclusion, in Brazil, despite recent developments of legal framework and practices related to land, does not have a complete land administration system. The legal framework is extensive and often contradictory, processes are complex, expensive and take long, and there is still a long way until land and the information about land may be effectively managed

    Numerical predictions of a swirl combustor using complex chemistry fueled with ammonia/hydrogen blends

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    Ammonia, a chemical that contains high hydrogen quantities, has been presented as a candidate for the production of clean power generation and aerospace propulsion. Although ammonia can deliver more hydrogen per unit volume than liquid hydrogen itself, the use of ammonia in combustion systems comes with the detrimental production of nitrogen oxides, which are emissions that have up to 300 times the greenhouse potential of carbon dioxide. This factor, combined with the lower energy density of ammonia, makes new studies crucial to enable the use of the molecule through methods that reduce emissions whilst ensuring that enough power is produced to support high-energy intensive applications. Thus, this paper presents a numerical study based on the use of novel reaction models employed to characterize ammonia combustion systems. The models are used to obtain Reynolds Averaged Navier-Stokes (RANS) simulations via Star-CCM+ with complex chemistry of a 70%–30% (mol) ammonia–hydrogen blend that is currently under investigations elsewhere. A fixed equivalence ratio (1.2), medium swirl (0.8), and confined conditions are employed to determine the flame and species propagation at various operating atmospheres and temperature inlet values. The study is then expanded to high inlet temperatures, high pressures, and high flowrates at different confinement boundary conditions. The results denote how the production of NOx emissions remains stable and under 400 ppm, whilst higher concentrations of both hydrogen and unreacted ammonia are found in the flue gases under high power conditions. The reduction of heat losses (thus higher temperature boundary conditions) has a crucial impact on further destruction of ammonia post-flame, with a raise in hydrogen, water, and nitrogen through the system, thus presenting an opportunity of combustion efficiency improvement of this blend by reducing heat losses. Final discussions are presented as a method to raise power whilst employing ammonia for gas turbine systems

    Resonant inelastic x-ray scattering (RIXS) spectra of magnesium diboride

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    Using the tight-binding linear muffin-tin orbitals method, the soft x-ray fluorescence K-emission spectra of boron in MgB_2, excited close to the absorption edge, are estimated. In the calculations the angle of incidence between the direction of the incoming photon and the hexagonal axis of the specimen is 60 degrees and 75 degrees. Comparison with experiment is possible in the former case where good agreement is found. Furthermore, another resonant feature below the Fermi energy is predicted for the larger angle. This feature can be related to the excitations to the antibonding B pi-band in the neighbourhood of the L-H line in the Brillouin zone.Comment: 4 pages with 4 figure

    Efficacy of anidulafungin in 539 patients with invasive candidiasis: a patient-level pooled analysis of six clinical trials

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    Item does not contain fulltextObjectives: To evaluate the efficacy of anidulafungin for the treatment of candidaemia and invasive candidiasis in a large dataset, including patients with deep-seated tissue candidiasis, neutropenia and infection due to non- albicans Candida species. Methods: Data were pooled from six prospective, multicentre, multinational studies: four open-label, non-comparative studies of anidulafungin and two double-blind, double-dummy, randomized studies of anidulafungin versus caspofungin (clinical trial registrations: NCT00496197, NCT00548262, NCT00537329, NCT00689338, NCT00806351 and NCT00805740; ClinicalTrials.gov). In all studies, patients with culture-confirmed invasive candidiasis received a single intravenous (iv) loading dose of anidulafungin 200 mg on day 1, followed by 100 mg once-daily. Switch to oral fluconazole or voriconazole was permitted after 5-10 days of iv treatment in all studies except one. Antifungal treatment (iv plus oral therapy if applicable) was maintained for >/=14 days after the last positive Candida culture. The primary endpoint was successful global response at end of iv therapy (EOivT) in the modified ITT (mITT) population. Results: In total, 539 patients were included (mITT population). The most common baseline Candida species were Candida albicans (47.9%), Candida glabrata (21.0%), Candida tropicalis (13.7%), Candida parapsilosis (13.2%) and Candida krusei (3.5%). Median duration of anidulafungin iv treatment was 10.0 days. The global response success rate at EOivT was 76.4% (95% CI 72.9%-80.0%). All-cause mortality was 13.0% on day 14 and 19.1% on day 28. Adverse events (AEs) were consistent with the known AE profile for anidulafungin. Conclusions: These data demonstrate that anidulafungin is effective for treatment of candidaemia and invasive candidiasis in a broad patient population

    Measurement of W Polarisation at LEP

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    The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the polarisation of W bosons, and its dependence on the W boson production angle. The fraction of longitudinally polarised W bosons is measured to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and the second systematic, in agreement with the Standard Model expectation

    Measurement of W Polarisation at LEP

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    The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the polarisation of W bosons, and its dependence on the W boson production angle. The fraction of longitudinally polarised W bosons is measured to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and the second systematic, in agreement with the Standard Model expectation

    Search for Anomalous Couplings in the Higgs Sector at LEP

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    Anomalous couplings of the Higgs boson are searched for through the processes e^+ e^- -> H gamma, e^+ e^- -> e^+ e^- H and e^+ e^- -> HZ. The mass range 70 GeV < m_H < 190 GeV is explored using 602 pb^-1 of integrated luminosity collected with the L3 detector at LEP at centre-of-mass energies sqrt(s)=189-209 GeV. The Higgs decay channels H -> ffbar, H -> gamma gamma, H -> Z\gamma and H -> WW^(*) are considered and no evidence is found for anomalous Higgs production or decay. Limits on the anomalous couplings d, db, Delta(g1z), Delta(kappa_gamma) and xi^2 are derived as well as limits on the H -> gamma gamma and H -> Z gamma decay rates

    Z Boson Pair-Production at LEP

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    Events stemming from the pair-production of Z bosons in e^+e^- collisions are studied using 217.4 pb^-1 of data collected with the L3 detector at centre-of-mass energies from 200 GeV up to 209 GeV. The special case of events with b quarks is also investigated. Combining these events with those collected at lower centre-of-mass energies, the Standard Model predictions for the production mechanism are verified. In addition, limits are set on anomalous couplings of neutral gauge bosons and on effects of extra space dimensions

    Study of the e+e- -> Ze+e- process at LEP

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    The cross section of the process e+e- -> Ze+e is measured with 0.7fb^-1 of data collected with the L3 detector at LEP. Decays of the Z boson into quarks and muons are considered at centre-of-mass energies ranging from 183GeV up to 209GeV. The measurements are found to agree with Standard Model predictions, achieving a precision of about 10% for the hadronic channel

    Inclusive Lambda Production in Two-Photon Collisions at LEP

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    The reactions e^+e^- -> e^+e^- Lambda X and e^+e^- -> e^+e^- Lambda X are studied using data collected at LEP with the L3 detector at centre-of-mass energies between 189 and 209 GeV. Inclusive differential cross sections are measured as a function of the lambda transverse momentum, p_t, and pseudo-rapidity, eta, in the ranges 0.4 GeV < p_t < 2.5 GeV and |\eta| < 1.2. The data are compared to Monte Carlo predictions. The differential cross section as a function of p_t is well described by an exponential of the form A exp (- p_t / )$
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