1,070 research outputs found

    Lichen taxonomic composition from MustafaKemalpaºa, Bursa district (Turkey)

    Get PDF
    A total of 130 lichen taxa belonging to 24 families in Ascomycotina are listed for MustafaKemalPaºa, NW Turkey. Tuckneraria laureri and Usnea substerilis are newly recordeds for Turkey. Distribution and substrates are presented

    Thermal behaviors of light unflavored tensor mesons in the framework of QCD sum rule

    Get PDF
    In this study, we investigate the sensitivity of the masses and decay constants of the light f2(1270)f_{2}(1270) and a2(1320)a_{2}(1320) tensor mesons to the temperature using QCD sum rule approach. In our calculations, we take into account the additional operators appearing in operator product expansion at finite temperature. It is obtained that at deconfinement temperature the decay constants and masses decrease with amount of 6%6\% and 96%96\% compared to their vacuum values, respectively. Our results on the masses at zero temperature are consistent with the vacuum sum rules predictions as well as the experimental data.Comment: 4 Pages and 1 Table, Prepared for the proceeding of the 4th International Conference on Hadron Physics (TROIA'14

    Three new lichenicolous fungi records for Turkey and Asia

    Get PDF
    Three lichenicolous fungi, Abrothallus peyritschii, Lichenochora verrucicola and Sclerococcum montagnei, collected from Burdur and Bitlis provinces, are reported as new to Turkey, the latter species is also new to Asia. Short descriptions, including geographical distributions, hosts and comparisons with similar taxa are provided

    Robust Upward Dispersion of the Neutron Spin Resonance in the Heavy Fermion Superconductor Ce1x_{1-x}Ybx_{x}CoIn5_5

    Get PDF
    The neutron spin resonance is a collective magnetic excitation that appears in copper oxide, iron pnictide, and heavy fermion unconventional superconductors. Although the resonance is commonly associated with a spin-exciton due to the dd(s±s^{\pm})-wave symmetry of the superconducting order parameter, it has also been proposed to be a magnon-like excitation appearing in the superconducting state. Here we use inelastic neutron scattering to demonstrate that the resonance in the heavy fermion superconductor Ce1x_{1-x}Ybx_{x}CoIn5_5 with x=0,0.05,0.3x=0,0.05,0.3 has a ring-like upward dispersion that is robust against Yb-doping. By comparing our experimental data with random phase approximation calculation using the electronic structure and the momentum dependence of the dx2y2d_{x^2-y^2}-wave superconducting gap determined from scanning tunneling microscopy for CeCoIn5_5, we conclude the robust upward dispersing resonance mode in Ce1x_{1-x}Ybx_{x}CoIn5_5 is inconsistent with the downward dispersion predicted within the spin-exciton scenario.Comment: Supplementary Information available upon reques

    Nature of the spin resonance mode in CeCoIn5_5

    Full text link
    Spin-fluctuation-mediated unconventional superconductivity can emerge at the border of magnetism, featuring a superconducting order parameter that changes sign in momentum space. Detection of such a sign-change is experimentally challenging, since most probes are not phase-sensitive. The observation of a spin resonance mode (SRM) from inelastic neutron scattering is often seen as strong phase-sensitive evidence for a sign-changing superconducting order parameter, by assuming the SRM is a spin-excitonic bound state. Here, we show that for the heavy fermion superconductor CeCoIn5_5, its SRM defies expectations for a spin-excitonic bound state, and is not a manifestation of sign-changing superconductivity. Instead, the SRM in CeCoIn5_5 likely arises from a reduction of damping to a magnon-like mode in the superconducting state, due to its proximity to magnetic quantum criticality. Our findings emphasize the need for more stringent tests of whether SRMs are spin-excitonic, when using their presence to evidence sign-changing superconductivity.Comment: accepted for publication in Communications Physic

    Effect of ligamenta flava hypertrophy on lumbar disc herniation with contralateral symptoms and signs: a clinical and morphometric study

    Get PDF
    Introduction: The purpose of this study was to determine whether ligamentum flavum hypertrophy among disc herniated patients causes contralateral pain symptoms For this reason we measured the thickness of the ligament in disc herniated patients with ipsilateral or contralateral symptoms

    The Notch pathway is a critical regulator of angiogenesis in a skin model of ischemia

    Get PDF
    WOS: 000355334000001PubMed ID: 25834117The Notch pathway is definitely required for normal vascular development. Although the contribution of Notch in postnatal angiogenesis is the focus of intense investigation, the implication of Notch in reparative neovascularization in the skin remains unexplored. In this study, we investigated Notch changes using a skin model of ischemia. Thirty Sprague-Dawley rats were divided into two groups. In the surgery group (n = 24), a caudally based dorsal skin flap was raised and sutured back into its initial position. In the control group, no surgical procedure was performed. Tissue biopsies were obtained at different time intervals. Tissue specimens were assessed for Delta-like ligand 4 (DLL4) and vascular endothelial growth factor (VEGF) gene expression by real-time polymerase chain reaction (PCR). Immunohistochemical staining was used for detection of DLL4 in tissue materials. Quantitative assessment of skin flap microvasculature was made. Compared with normoperfused tissue, VEGF and DLL4 expressions increased significantly (p < 0.01). Immunohistochemical analysis revealed weak and patchy expression of DLL4 in microvascular endothelial cells of normoperfused tissues. Conversely, DLL4 expression was upregulated in capillary endothelial cells after ischemia. In conclusion, in this study we have shown that the Notch ligand DLL4 is upregulated in skin tissue after ischemia. A deeper understanding of these fundamental principles will aid in the development of new avenues for the treatment of blood vessel-related skin pathologies.Baskent University Research FundBaskent UniversityThis study was approved by Baskent University Ethical Committee for Experimental Research on Animals and supported by Baskent University Research Fund

    Structural insights on TRPV5 gating by endogenous modulators.

    Get PDF
    TRPV5 is a transient receptor potential channel involved in calcium reabsorption. Here we investigate the interaction of two endogenous modulators with TRPV5. Both phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and calmodulin (CaM) have been shown to directly bind to TRPV5 and activate or inactivate the channel, respectively. Using cryo-electron microscopy (cryo-EM), we determined TRPV5 structures in the presence of dioctanoyl PI(4,5)P2 and CaM. The PI(4,5)P2 structure reveals a binding site between the N-linker, S4-S5 linker and S6 helix of TRPV5. These interactions with PI(4,5)P2 induce conformational rearrangements in the lower gate, opening the channel. The CaM structure reveals two TRPV5 C-terminal peptides anchoring a single CaM molecule and that calcium inhibition is mediated through a cation-π interaction between Lys116 on the C-lobe of calcium-activated CaM and Trp583 at the intracellular gate of TRPV5. Overall, this investigation provides insight into the endogenous modulation of TRPV5, which has the potential to guide drug discovery
    corecore