461 research outputs found

    Global Monetary Conditions versus Country-Specific Factors in the Determination of Emerging Market Debt Spreads

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    We offer evidence in this paper that US interest rate policy has an important influence in the determination of credit spreads on emerging market bonds over US benchmark treasuries, and therefore on their cost of capital. Our analysis improves upon the existing literature and understanding, by addressing the dynamics of market expectations in shaping views on interest rate and monetary policy changes, and by recognizing non-linearities in the link between US interest rates and emerging market bond spreads, as the level of interest rates affects the market's perceived probability of default and the solvency of emerging market borrowers. For a country with a moderate level of debt, repayment prospects would remain good in the face of an increase in US interest rates, so there would be little increase in spreads. A country close to the borderline of solvency would face a steeper increase in the spreads. Simulations of a 200 basis points (bps) increase in US short-term interest rates (ignoring any change in the US 10 year Treasury rate) show an increase in emerging market spreads ranging from 6 bps to 65 bps, depending on debt/GDP ratios.emerging market spreads, currency crises, global monetary conditions

    Towards a rapidly rotating liquid sodium dynamo experiment

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    The main characteristics of the Earth's dynamo are reviewed. The combined actions of Coriolisand Lorentz forces lead to the so--called ``magnetostrophic'' regime. We derive an estimate of the power needed to sustain the magnetic field in this regime. We show that an experimentwith liquid sodium can be designed to operate in the magnetostrophic regime. Such an experiment would bring most valuable informations on the mechanisms of planetary dynamos. In order toprepare this large--scale experiment and explore the magnetostrophic balance, a smaller scale liquid sodium set--up has been designed and is being built. It consists of a rapidly rotating spherical shell filled with liquid sodium, in which motions are set by spinning at a different rotation rate an inner core permeated by a strong magnetic field. We discuss the processes that can be explored with this new device

    L’outil idéal. Analyse du standard Levallois des sites moustériens d’Hermies (Nord de la France)

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    Des fouilles récentes sur deux gisements moustériens de plein air du nord de la France ont mis au jour plusieurs niveaux d’occupation bien conservés où des activités de taille ont été conduites au sein de postes de débitage clairement délimités. Le débitage du silex, d’origine locale, était totalement orienté vers la production d’éclats préférentiels selon un schéma Levallois linéal. En confrontant les données fournies par différentes approches (analyse technologique, remontages, analyse spatiale, tracéologie) nous avons tenté d’identifier les produits finis répondant aux exigences des utilisateurs. Une analyse statistique portant sur la quasi-totalité des produits finis, soit 127 éclats préférentiels, a montré que les critères de sélection des pièces produites à des fins d’usage de boucherie se limitaient essentiellement au choix des éclats préférentiels présentant un profil longitudinal strictement rectiligne. La production, bien que fortement normalisée, admettait une certaine variabilité dimensionnelle ; au sein de cette gamme, les utilisateurs ont, dans un des niveaux, sélectionné deux formats assez lâches correspondant à deux types d’utilisation distincts. On pose également le problème de l’économie du débitage et des rapports entre la production effectuée sur place et les produits importés

    Motivations of patients seeking supportive care for cancer from physicians prescribing homeopathic or conventional medicines: results of an observational cross-sectional study

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    Background & aimsThe motivations of patients who consult a homeopathic (GP-Ho) or conventional (GP-CM) general practitioner for supportive care during cancer treatment have not been widely studied. We investigated the reasons why cancer patients consult a GP-Ho versus a GP-CM for supportive care and the GPs' motivations for their prescriptions.MethodsThis observational survey was carried out in France between October 2008 and October 2011. GPs across France were randomly selected and asked to recruit four cancer patients each. At inclusion, the sociodemographic and clinical (including psychological) characteristics and medical history of the patients were recorded by the GPs and the patients noted their quality of life (QoL) and anxiety/depression using the Quality of Life Questionnaire-C30 (QLQ-C30) and Hospital Anxiety and Depression Scale (HADS) self-questionnaires. The main motivations of the patients regarding the type of GP consultation and the main reasons for the GPs' prescriptions were recorded.ResultsSix hundred and forty four patients were included in the analysis: 399 consulted a GP-CM (n = 112) and 245 a GP-Ho (n = 73). Patients consulting a GP-Ho were more often female [OR = 1.93; 95%CI: 1.11–3.35; p = 0.02], employed in a professional capacity [OR = 6.57; 95%CI: 1.96–21.99; p = 0.002], have a shorter time since cancer diagnosis [OR = 2.19; 95%CI: 1.24–3.87; p = 0.007], have received targeted anticancer therapy [OR = 3.70; 95%CI: 1.67–8.18; p = 0.001] and have a high QLQ-C30 score for constipation [OR = 1.01; 95%CI: 1.00–1.02; p = 0.001]. Patients mainly consulted a GP-Ho to receive overall care (73.5% vs. 64.9%; p = 0.024) and medicines to prevent anticancer treatment-related side-effects (63.7% vs. 41.4%; p < 0.0001). In contrast, patients consulted a GP-CM to receive psychological care (50.1% vs. 40.8%; p = 0.021) and more information regarding the oncologists' strategic decisions (p < 0.0001). There was a significantly greater prescription of psychotropic drugs by GP-CM (53.7% vs. 22.4%, p < 0.0001).ConclusionsPatients consulting a GP-Ho or GP-CM had different motivations for seeking supportive care. There was a significantly greater prescription of psychotropic drugs by GP-CM

    Experimental evidence of Alfv\'en wave propagation in a Gallium alloy

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    Experiments with a liquid metal alloy, galinstan, are reported and show clear evidence of Alfv\'en wave propagation as well as resonance of Alfv\'en modes. Galinstan is liquid at room temperature, and although its electrical conductivity is not as large as that of liquid sodium or NaK, it has still been possible to study Alfv\'en waves, thanks to the use of intense magnetic fi elds, up to 13 teslas. The maximal values of Lundquist number, around 60, are similar to that of the reference experimental study by Jameson [1]. The generation mechanism for Alfv\'en waves and their refl ection is studied carefully. Numerical simulations have been performed and have been able to reproduce the experimental results despite the fact that the simulated magnetic Prandtl number was much larger than that of galinstan. An originality of the present study is that a poloidal disturbance (magnetic and velocity fields) is generated, allowing us to track its propagation from outside the conducting domain, hence without interfering.Comment: 19 pages; Physics of Fluids (2011)

    Spatial–temporal variations of water vapor content over Ethiopia: a study using GPS observations and the ECMWF model

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    We characterize the spatial–temporal variability of integrated water vapor (IWV) in Ethiopia from a network of global positioning system (GPS) stations and the European Center for Medium range Weather Forecasting (ECMWF) model. The IWV computed from the ECMWF model is integrated from the height of the GPS stations on 60 pressure levels to take both the actual earth surface and the model orography discrepancies into account. First, we compare the IWV estimated from GPS and from the model. The bias varies from site to site, and the correlation coefficients between the two data sets exceed 0.85 at different time scales. The results of this study show that the general ECMWF IWV trend is underestimation over highlands and overestimation over lowlands for wet periods, and overestimation over high- lands and underestimation over lowlands for dry periods with very few exceptional stations. Second, we observe the spatial variation of the IWV. High values are obtained in those stations that are located in the north-eastern (Afar depression) sites and the south-western part of the country. This distribution is related to the spatial variability of the climate in Ethiopia. Finally, we study the seasonal cycle and inter-annual variability of IWV for all stations over Ethiopia. The main result is the strong inter-annual vari- ability observed for the dry seasons

    Quantifying sediment mass redistribution from joint time-lapse gravimetry and photogrammetry surveys

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    The accurate quantification of sediment mass redistribution is central to the study of surface processes, yet it remains a challenging task. Here we test a new combination of terrestrial gravity and drone photogrammetry methods to quantify sediment mass redistribution over a 1 km2 area. Gravity and photogrammetry are complementary methods. Indeed, gravity changes are sensitive to mass changes and to their location. Thus, by using photogrammetry data to constrain this location, the sediment mass can be properly estimated from the gravity data. We carried out three joint gravimetry–photogrammetry surveys, once a year in 2015, 2016 and 2017, over a 1 km^2 area in southern Taiwan, featuring both a wide meander of the Laonong River and a slow landslide. We first removed the gravity changes from non-sediment effects, such as tides, groundwater, surface displacements and air pressure variations. Then, we inverted the density of the sediment with an attempt to distinguish the density of the landslide from the density of the river sediments. We eventually estimate an average loss of 3.7 \ub1 0.4  7 10^9 kg of sediment from 2015 to 2017 mostly due to the slow landslide. Although the gravity devices used in this study are expensive and need week-long surveys, new instrumentation currently being developed will enable dense and continuous measurements at lower cost, making the method that has been developed and tested in this study well-suited for the estimation of erosion, sediment transfer and deposition in landscapes

    Test 1157: John Deere 2630 and 2640 Diesel

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    EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The fuel used and the maintenance operations must also conform to the published information delivered with the tractor. The tractor is then limbered-up for 1 hour on drawbar work in accordance with the manufacturers published recommendations. The manufacturer’s representative is present to make appropriate decisions regarding mechanical adjustments. The tractor is equipped with approximately the amount of added ballast that is used during maximum drawbar tests. The tire tread-bar height must be at least 65% of new tread height prior to the maximum power run. BELT OR POWER TAKE-OFF PERFORMANCE Maximum Power and Fuel Consumption. The manufacturer’s representative makes carburetor, fuel pump, ignition and governor control settings which remain unchanged throughout tall subsequent runs. The governor and the manually operated governor control lever is set to provide the high-idle speed specified by the manufacturer for maximum power. Maximum power is measured by connecting the belt pulley or the power take-off to a dynamometer. The dynamometer load is then gradually increased until the engine is operating at the rated speed specified by the manufacturer for maximum power. The corresponding fuel consumption is measured. Varying Power and Fuel Consumption. Six different horsepower levels are used to show corresponding fuel consumption rates and how the governor causes the engine to react to the following changes in dynamometer load: 85% of the dynamometer torque at maximum power; minimum dynamometer torque, ½ the 85% torque; maximum power; ¼ and ¾ of the 85% torque. Since at tractor is generally subjected to varying loads the average of the results in this test serve well for predicting the fuel consumption of a tractor in general usage. DRAWBAR PERFORMANCE All engine adjustments are the same as those used in the belt or power take-off tests. If the manufacturer specifies a different rated crankshaft speed for drawbar operations, then the position of the manually operated governor control is changed to provide the high-idle speed specified by the manufacturer in the operating instructions. Varying Power and Fuel Consumption With Ballast. The varying power runs are made to show the effect of speed-control devices (engine governor, automatic transmissions, etc.) on horsepower, speed and fuel consumption. These runs are made around the entire test course with has two 180 degree turns with a minimum radius of 50 feet. The drawbar pull is set at 3 different levels as follows: (1) as near to the pull a maximum power as possible and still have the tractor maintain the travel speed at maximum horsepower on the straight sections of the test course; (2) 75% of the pull at maximum power; and (3) 50% of the pull at maximum power. Prior to 1958, fuel consumption data (10 hour test) were shown only for the pull obtained at maximum power for tractors having torque converters and at 75% of the pull obtained at maximum power for gear-type tractors. Maximum Power With Ballast. Maximum power is measured on straight level sections of the test course. Data are shown for not more that 12 different gears or travel speeds. Some gears or travel speeds may be omitted because of high slippage of the traction members or because the travel speed may exceed the safe-limit for the test course. The maximum safe speed for the Nebraska Test course has been set at 15 miles per hour. The slippage limits have been set at 15% and 7% for pneumatic tires and steel tracks or lugs, respectively. Higher slippage gives widely varying results. Maximum Power Without Ballast. All added ballast is removed from the tractor. The maximum drawbar power of the tractor is determined by the same procedure used for getting maximum power with ballast. The gear (or travel speed) is the same as that used in the 10-hours test. Varying Power and Travel Speed With Ballast. Travel speeds corresponding to drawbar pulls beyond the maximum power range are obtained to show the “lugging ability” of the tractor. The run starts with the pull at maximum power; then additional drawbar pull is applied to cause decreasing speeds. The run is ended by one of three conditions; (1) maximum pull is obtained, (2) the maximum slippage limit is reached, or (3) some other operating limit is reached

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

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    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN
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