Coupling constants of D∗DsKD^*D_sK and Ds∗DKD_s^*DK processes

We calculate the coupling constants of $D^*D_sK$ and $D_s^*DK$ vertices using the QCD sum rules technique. We compare results obtained in the limit of SU(4) symmetry and found that the symmetry is broken on the order of 40%.Comment: 4 pages, 3 ps figures. Talk presented in the 18 Workshop on Hadron Interactions, IFUSP, Sao Paulo, Brazil, may 22-24 of 200

A QCD sum rules calculation of the J/ψDs∗DsJ/\psi D_s^* D_s strong coupling constant

In this work, we calculate the form factors and the coupling constant of the strange-charmed vertex $J/\psi D_s^* D_s$ in the framework of the QCD sum rules by studying their three-point correlation functions. All the possible off-shell cases are considered, $D_s$, $D_s^*$ and $J/\psi$, resulting in three different form factors. These form factors are extrapolated to the pole of their respective off-shell mesons, giving the same coupling constant for the process. Our final result for the $J/\psi D_s^* D_s$ coupling constant is $g_{J/\psi D^*_s D_s} = 4.30^{+0.42}_{-0.37}\text{GeV}^{-1}$.Comment: 17 pages, 4 figure

Hybrid Photonic Crystal Fiber Sensing Of High Hydrostatic Pressure

The opto-mechanical response of Hybrid Photonic Crystal Fiber (HPCF) with Ge-doped inclusions is numerically modeled for high hydrostatic pressure sensing purpose. A typical photonic crystal fiber (PCF) consists of a silica solidcore and a cladding with a hexagonal lattice of air-holes. The HPCF is similar to the regular PCF, but a horizontal line of air-holes is substituted by solid high index rods of Ge-doped silica. The optical guidance in HPCFs is supported combining two physical effects: the modified total internal reflection and the photonic bandgap. In such fibers, the Gedoped inclusions induce residual birefringence. In our analysis, we evaluate the susceptibility of the phase modal birefringence and group birefringence to hydrostatic pressure. The analyses were performed at a photonic bandgap with central wavelength near to 1350 nm. The polarimetric pressure sensitivity is about 10 rad/MPa x m at λ = 1175 nm. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).7753Oz Optics,Simbol Test Systems, Inc.,FISO Technologies, Inc.,CMC Microsystems Corporation,Innovative Economy: National Strategic Reference FrameworkCerqueira, A.S., Hybrid photonic crystal fiber (2006) Opt. Express, 14 (2), pp. 926-931Cerqueira, A.S., Recent progress and novel applications of photonic crystal fibers (2010) Rep. Prog. Phys., 73, p. 023301Cerqueira, A.S., Birefringence properties of hybrid photonic crystal fibers (2009) Proceedings of Microwave and Optoelectronics Conference (IMOC 2009), pp. 804-806. , Belem, Brazil, 03-06, NovemberFranco, M.A.R., Thermal tunability of photonic bandgaps in photonic crystal fibers selectively filled with nematic liquid crystal Proceedings of 2nd Workshop on Specialty Optical Fibers and Their Applications (WSOF-2), Oaxaca, Mexico, 13-15, October, (2010)Fleming, J.W., Dispersion in GeO2 -SiO2 glasses (1984) Appl. Opt., 23 (24), pp. 4486-4493Martynkien, T., Highly birefringent microstructured fibers with enhanced sensitivity to hydrostatic pressure (2010) Opt. Express, 18 (14), pp. 15113-15121Kühn, B., Schadrack, R., Thermal expansion of synthetic fused silica as a function of OH content and fictive temperature (2009) J. Non-Cryst. Solids, 355, pp. 323-326Gupta, D., Kumar, A., Thyagarajan, K., Polarization mode dispersion in single mode optical fibers due to core-ellipticity (2006) Opt. Commun., 263, pp. 36-41Koshiba, M., (1992) Optical Waveguide Theory by the Finite Element Method, pp. 133-160. , KTK Scientific Publishers and Kluwer Academic Publishers, TokyoUrbanczyk, W., Martynkien, T., Bock, W.J., Dispersion effects in elliptical-core highly birefringent fibers (2001) Appl. Opt., 40 (12), pp. 1911-1920Olszewski, J., Birefringence analysis in photonic crystal fibers with germanium-doped core (2009) J. Opt. A: Pure Appl. Opt., 11, pp. 1-10Martynkien, T., Urbanczyk, W., Modeling of spectral characteristics of Corning PMF-38 highly birefringent fiber (2002) Optik, 113 (1), pp. 25-30Hlubina, P., Broad spectral range measurements and modelling of birefringence dispersion in two-mode elliptical-core fibres (2010) J. Opt., 12, pp. 1-8Martynkien, T., Birefringence in microstructure fiber with elliptical GeO2 highly doped inclusion in the core (2008) Opt. Lett., 33 (23), pp. 2764-2766Verbandt, Y., Polarimetric Optical Fiber Sensors: Aspects of Sensitivity and Practical Implementation (1997) Opt. Rev., 4 (1 A), pp. 75-79Lagakos, N., Bucaro, J.A., Hughes, R., Acoustic sensitivity predictions of single-mode optical fibers using Brillouin scattering (1980) Appl. Opt., 19 (21), pp. 3668-3670Chiang, K.S., Sceats, Wong, D., Ultraviolet photolytic-induced changes in optical fibers: The thermal expansion coefficient (1993) Opt. Lett., 18 (12), pp. 965-96

Whole genome sequencing,molecular typing and in vivovirulence of OXA-48-producingEscherichia coli isolates includingST131 H30-Rx, H22 and H41subclones

Carbapenem-resistant Enterobacteriaceae, including the increasingly reported OXA-48 Escherichia coli producers, are an emerging public health threat worldwide. Due to their alarming detection in our healthcare setting and their possible presence in the community, seven OXA-48-producing, extraintestinal pathogenic E. coli were analysed by whole genome sequencing as well as conventional tools, and tested for in vivo virulence. As a result, five E. coli OXA-48-producing subclones were detected (O25:H4-ST131/PST43-fimH30-virotype E; O25:H4-ST131/PST9-fimH22-virotype D5, O16:H5-ST131/ PST506-fimH41; O25:H5-ST83/PST207 and O9:H25-ST58/PST24). Four ST131 and one ST83 isolates satisfied the ExPEC status, and all except the O16:H5 ST131 isolate were UPEC. All isolates exhibited local inflammatory response with extensive subcutaneous necrosis but low lethality when tested in a mouse sepsis model. The blaOXA-48 gene was located in MOBP131/IncL plasmids (four isolates) or within the chromosome (three ST131 H30-Rx isolates), carried by Tn1999-like elements. All, except the ST83 isolate, were multidrug-resistant, with additional plasmids acting as vehicles for the spread of various resistance genes. This is the first study to analyse the whole genome sequences of blaOXA-48-positive ST131, ST58 and ST83 E. coli isolates in conjunction with experimental data, and to evaluate the in vivo virulence of blaOXA-48 isolates, which pose an important challenge to patient management

High proportion of smaller ranged hummingbird species coincides with ecological specialization across the Americas.

Ecological communities that experience stable climate conditions have been speculated to preserve more specialized interspecific associations and have higher proportions of smaller ranged species (SRS). Thus, areas with disproportionally large numbers of SRS are expected to coincide geographically with a high degree of community-level ecological specialization, but this suggestion remains poorly supported with empirical evidence. Here, we analysed data for hummingbird resource specialization, range size, contemporary climate, and Late Quaternary climate stability for 46 hummingbird-plant mutualistic networks distributed across the Americas, representing 130 hummingbird species (ca 40% of all hummingbird species). We demonstrate a positive relationship between the proportion of SRS of hummingbirds and community-level specialization, i.e. the division of the floral niche among coexisting hummingbird species. This relationship remained strong even when accounting for climate, furthermore, the effect of SRS on specialization was far stronger than the effect of specialization on SRS, suggesting that climate largely influences specialization through species' range-size dynamics. Irrespective of the exact mechanism involved, our results indicate that communities consisting of higher proportions of SRS may be vulnerable to disturbance not only because of their small geographical ranges, but also because of their high degree of specialization

Utility of Cardiac Magnetic Resonance to assess association between admission hyperglycemia and myocardial damage in patients with reperfused ST-Segment Elevation Myocardial Infarction

International audienceAbstract: Aims: to investigate the association between admission hyperglycemia and myocardial damage in patients with ST-segment elevation myocardial infarction (STEMI) using Cardiac Magnetic Resonance (CMR). Methods: We analyzed 113 patients with STEMI treated with successful primary percutaneous coronary intervention. Admission hyperglycemia was defined as a glucose level >= 7.8 mmol/l. Contrast-enhanced CMR was performed between 3 and 7 days after reperfusion to evaluate left ventricular function and perfusion data after injection of gadolinium-DTPA. First-pass images (FP), providing assessment of microvascular obstruction and Late Gadolinium Enhanced images (DE), reflecting the extent of infarction, were investigated and the extent of transmural tissue damage was determined by visual scores. Results: Patients with a supramedian FP and DE scores more frequently had left anterior descending culprit artery (p = 0.02 and < 0.001), multivessel disease (p = 0.02 for both) and hyperglycemia (p < 0.001). Moreover, they were characterized by higher levels of HbA(1c) (p = 0.01 and 0.04), peak plasma Creatine Kinase (p < 0.001), left ventricular end-systolic volume (p = 0.005 and < 0.001), and lower left ventricular ejection fraction (p = 0.001 and < 0.001). In a multivariate model, admission hyperglycemia remains independently associated with increased FP and DE scores. Conclusion: Our results show the existence of a strong relationship between glucose metabolism impairment and myocardial damage in patients with STEMI. Further studies are needed to show if aggressive glucose control improves myocardial perfusion, which could be assessed using CMR