934 research outputs found
Power, Techno-economics, and Transatlantic Relations in 1987-1999
This essay suggests that in 1987-1999 European elites, in their efforts of asymmetric balancing against the United States hegemony, decided to trade-off military capability for economic competitiveness. Thus, it documents a correlation between a) the reluctance of especially France and Germany during the 1990s to fully embrace and pursue the US-led RMA; and, b) the European Union's efforts since the late 1980s to challenge America's technological and economic supremacy in the aerospace sector. Two projects (Airbus and Galileo) indicate that the quest for strategic independence and the fear of reduced influence in international affairs were the driving forces behind European efforts to challenge the US commercial and technological supremacy in the aerospace sector in 1987-99. Furthermore, the article tries to identify what role the RMA played in this context (focusing in particular on Germany and France). It argues also that since the late 1980s (and especially during the 1990s), the European Commission and countries such as France and Germany perceived US policies in high-technology sectors (accentuated also by vigorous pursuit of the RMA) as limiting Europe’s abilities to advance its own agenda in international economic and security affairs
Determining European Options Values through Crank-Nicolson Method
Options are nowadays transacted within a lot of stock exchanges worldwide. The problem of options gets a special importance due to the fact that many of the managerial decisions can be assimilated to options. The paper deals with numerical methods of financial options evaluation. The mathematical model of determining the values of an option of European type is partial differential equation with an initial condition and two boundaries conditions, and for its solving, finite differences methods can be used. Out of these methods, the Crank-Nicolson method is proposed to be used. As Crank-Nicolson method is an implicit one, applying it leads to a linear system of equations, for whose solving the LU algorithm, Gauss method, Jacobi method, Gauss – Seidel method, method of successive over-relaxations are used.European options, values of an option, Crank – Nicolson Method, LU algorithm, Gauss method, Jacobi method, Gauss – Seidel method, method of successive over-relaxations
Cytotoxic activity of Pinus cembra L. needle extract: A preliminary study on HeLa cell line
The aim of this study was to investigate the cytotoxic effects of a hydromethanolic extract obtained from cembran pine needles in HeLa cell line. In this respect, the effects of needle extract on protein synthesis, viability, proliferation and cell cycle in HeLa cells were evaluated after 48 h treatment. Cembran pine needle extract dose-dependently decreased protein synthesis in HeLa cells causing 44.26% reduction in protein synthesis at 100µg/ml. At 25, 50 and 100µg/ml, it increased cell death in comparison with the control (20.99%, 21.49% and 23.63%, respectively vs. 9.83%). In addition, at 100µg/ml, cembran pine needle extract showed a remarkable antiproliferative effect whereas at 25 and 50µg/ml, it induced sub-G1 phase cells accumulation (11.68 ± 0.81% and 14.69 ± 0.56%, respectively in comparison with control, 6.03 ± 0.55%), an indicator of proapoptotic effects. Taken together, these results indicate that cembran pine needles are a source of compounds with antitumor potential which needs to be further investigated and exploited
Unusual Canine Distemper Virus Infection in Captive Raccoons (Procyon lotor)
Canine morbillivirus, also known as canine distemper virus (CDV), is the causative agent of canine distemper (CD), which is a serious contagious disease of canines, large felids, and, occasionally, raccoons. This study included seven raccoons from the Timisoara Zoological Garden, Romania. CDV was detected using RT-qPCR on blood samples, but several other exams were also performed—clinical, bacteriological, immunohistochemistry (IHC) and histopathology, toxicological screening, and necropsy—which confirmed CDV infection. Severe digestive disorders (diarrhea and frequent hematemesis) were observed. The necropsy findings included pseudo membranous gastroenteritis, congestion, and pulmonary edema in two raccoons. Immunohistochemistry showed immunolabeled CDV antigenantibodies on the viral nucleocapsid. Histopathology revealed lymphocyte depletion in mesenteric lymphnodes and intranuclear and intracytoplasmic inclusions in the enterocytes of the small intestine. Based on the RT-qPCR assay, laboratory tests, and the lesions observed, it was established that the raccoons were infected with CDV, which was the cause of death in two cases. The results from the necropsy, histology, and immunohistochemistry in the raccoons are comparable with reported CDV lesions in dogs. In conclusion, several exams may be performed to establish the etiology of possible interspecific viral infection, but only very specific exams can identify aCDV infection. Laboratory analyses must be completed by RT-qPCR assay or IHC to establish infection with uncommon viruses in raccoons with high accuracy
Observation of Exclusive Gamma Gamma Production in p pbar Collisions at sqrt{s}=1.96 TeV
We have observed exclusive \gamma\gamma production in proton-antiproton
collisions at \sqrt{s}=1.96 TeV, using data from 1.11 \pm 0.07 fb^{-1}
integrated luminosity taken by the Run II Collider Detector at Fermilab. We
selected events with two electromagnetic showers, each with transverse energy
E_T > 2.5 GeV and pseudorapidity |\eta| < 1.0, with no other particles detected
in -7.4 < \eta < +7.4. The two showers have similar E_T and azimuthal angle
separation \Delta\phi \sim \pi; 34 events have two charged particle tracks,
consistent with the QED process p \bar{p} to p + e^+e^- + \bar{p} by two-photon
exchange, while 43 events have no charged tracks. The number of these events
that are exclusive \pi^0\pi^0 is consistent with zero and is < 15 at 95% C.L.
The cross section for p\bar{p} to p+\gamma\gamma+\bar{p} with |\eta(\gamma)| <
1.0 and E_T(\gamma) > 2.5$ GeV is
2.48^{+0.40}_{-0.35}(stat)^{+0.40}_{-0.51}(syst) pb.Comment: 7 pages, 4 figure
Observation of the Baryonic Flavor-Changing Neutral Current Decay Lambda_b -> Lambda mu+ mu-
We report the first observation of the baryonic flavor-changing neutral
current decay Lambda_b -> Lambda mu+ mu- with 24 signal events and a
statistical significance of 5.8 Gaussian standard deviations. This measurement
uses ppbar collisions data sample corresponding to 6.8fb-1 at sqrt{s}=1.96TeV
collected by the CDF II detector at the Tevatron collider. The total and
differential branching ratios for Lambda_b -> Lambda mu+ mu- are measured. We
find B(Lambda_b -> Lambda mu+ mu-) = [1.73+-0.42(stat)+-0.55(syst)] x 10^{-6}.
We also report the first measurement of the differential branching ratio of B_s
-> phi mu+ mu- using 49 signal events. In addition, we report branching ratios
for B+ -> K+ mu+ mu-, B0 -> K0 mu+ mu-, and B -> K*(892) mu+ mu- decays.Comment: 8 pages, 2 figures, 4 tables. Submitted to Phys. Rev. Let
Combined search for the standard model Higgs boson decaying to a bb pair using the full CDF data set
We combine the results of searches for the standard model Higgs boson based
on the full CDF Run II data set obtained from sqrt(s) = 1.96 TeV p-pbar
collisions at the Fermilab Tevatron corresponding to an integrated luminosity
of 9.45/fb. The searches are conducted for Higgs bosons that are produced in
association with a W or Z boson, have masses in the range 90-150 GeV/c^2, and
decay into bb pairs. An excess of data is present that is inconsistent with the
background prediction at the level of 2.5 standard deviations (the most
significant local excess is 2.7 standard deviations).Comment: To be published in Phys. Rev. Lett (v2 contains minor updates based
on comments from PRL
Shrinking a large dataset to identify variables associated with increased risk of Plasmodium falciparum infection in Western Kenya
Large datasets are often not amenable to analysis using traditional single-step approaches. Here, our general objective was to apply imputation techniques, principal component analysis (PCA), elastic net and generalized linear models to a large dataset in a systematic approach to extract the most meaningful predictors for a health outcome. We extracted predictors for Plasmodium falciparum infection, from a large covariate dataset while facing limited numbers of observations, using data from the People, Animals, and their Zoonoses (PAZ) project to demonstrate these techniques: data collected from 415 homesteads in western Kenya, contained over 1500 variables that describe the health, environment, and social factors of the humans, livestock, and the homesteads in which they reside. The wide, sparse dataset was simplified to 42 predictors of P. falciparum malaria infection and wealth rankings were produced for all homesteads. The 42 predictors make biological sense and are supported by previous studies. This systematic data-mining approach we used would make many large datasets more manageable and informative for decision-making processes and health policy prioritization
Evidence for t\bar{t}\gamma Production and Measurement of \sigma_t\bar{t}\gamma / \sigma_t\bar{t}
Using data corresponding to 6.0/fb of ppbar collisions at sqrt(s) = 1.96 TeV
collected by the CDF II detector, we present a cross section measurement of
top-quark pair production with an additional radiated photon. The events are
selected by looking for a lepton, a photon, significant transverse momentum
imbalance, large total transverse energy, and three or more jets, with at least
one identified as containing a b quark. The ttbar+photon sample requires the
photon to have 10 GeV or more of transverse energy, and to be in the central
region. Using an event selection optimized for the ttbar+photon candidate
sample we measure the production cross section of, and the ratio of cross
sections of the two samples. Control samples in the dilepton+photon and
lepton+photon+\met, channels are constructed to aid in decay product
identification and background measurements. We observe 30 ttbar+photon
candidate events compared to the standard model expectation of 26.9 +/- 3.4
events. We measure the ttbar+photon cross section to be 0.18+0.08 pb, and the
ratio of the cross section of ttbar+photon to ttbar to be 0.024 +/- 0.009.
Assuming no ttbar+photon production, we observe a probability of 0.0015 of the
background events alone producing 30 events or more, corresponding to 3.0
standard deviations.Comment: 9 pages, 3 figure
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