Tetrahydrobiopterin analogues with NO-dependent pulmonary vasodilator properties

Reduced NO levels due to the deficiency of tetrahydrobiopterin (BH4) contribute to impaired vasodilation in pulmonary hypertension Due to the chemically unstable nature of BH4 it was hypothesised that oxidatively stable analogues of BR, would be able to support NO synthesis to improve Endothelial dysfunction in pulmonary hypertension Two analogues of BH4 namely 6-hydroxymethyl pterin (HMP) and 6-acetyl 7 7-dimethyl 7 8-dihydropterin (ADDP) were evaluated for vasodilator activity on precontracted rat pulmonary artery rings ADDP was administered to pulmonary hypertensive rats followed by measurement of pulmonary vascular resistance in perfused lungs and eNOS expression by immunohistochemistry ADDP and HMP caused significant relaxation in vitro in rat pulmonary arteries depleted of BH4 with a maximum relaxation at 0 3 mu M (both P<005) Vasodilator activity of ADDP and HMP was completely abolished following preincubation with the NO synthase inhibitor L-NAME ADDP and HMP did not alter relaxation induced by carbachol or spermine NONOate BH4 Itself did not produce relaxation In rats receiving ADDP 141 mg/kg/day pulmonary vasodilation induced by calcium ionophore A23187 was augmented and eNOS immunoreactivity was increased In conclusion ADDP and HMP are two analogues of BH4 which can act as oxidatively stable alternatives to BH4 in causing NO-mediated vasorelaxation Chronic treatment with ADDP resulted in Improvement of NO-mediated pulmonary artery dilation and enhanced expression of eNOS in the pulmonary vascular endothelium Chemically stable analogue, of BH4 may be able to limit endothelial dysfunction in the pulmonary vasculatur

Stories of Critical Moments Contributing to the Development of Applied Sport Psychology Practitioners

This study explored the stories of critical moments experienced by applied sport psychology practitioners. The 13 recruited practitioners (eight male and five female) were in different stages of their development (trainee, neophyte, and experienced) and were asked to tell one story about a critical moment that significantly contributed to their development as applied practitioners. Narrative analysis was used to explore the stories of critical moments. Four distinct narrative structures were evident; Re-birth, Rags to Riches, Tragedy, and The Quest. There was one consistent narrative feature that supported these plots: critical moments contribute towards an alignment between a practitioner’s beliefs and behaviour, which supports the development of a congruent philosophy of practice and the environment they choose to work within. We recommend future research, such as the use of narrative analysis to explore alternative narrative structures and the investigation of successful and unsuccessful consultancy experiences

Photonic mode density effects on single-molecule fluorescence blinking

We investigated the influence of the photonic mode density (PMD) on the triplet dynamics of individual chromophores on a dielectric interface by comparing their response in the presence and absence of a nearby gold film. Lifetimes of the excited singlet state were evaluated in ordet to measure directly the PMD at the molecules position. Triplet state lifetimes were simultaneously determined by statistical analysis of the detection time of the fluorescence photons. The observed singlet decay rates are in agreement with the predicted PMD for molecules with different orientations. The triplet decay rate is modified in a fashion correlated to the singlet decay rate. These results show that PMD engineering can lead to an important suppression of the fluorescence, introducing a novel aspect of the physical mechanism to enhance fluorescence intensity in PMD-enhancing systems such as plasmonic devices

Metallopanstimulin as a marker for head and neck cancer

BACKGROUND: Metallopanstimulin (MPS-1) is a ribosomal protein that is found in elevated amounts in the sera of patients with head and neck squamous cell carcinoma (HNSCC). We used a test, denoted MPS-H, which detects MPS-1 and MPS-1-like proteins, to determine the relationship between MPS-H serum levels and clinical status of patients with, or at risk for, HNSCC. PATIENTS AND METHODS: A total of 125 patients were prospectively enrolled from a university head and neck oncology clinic. Participants included only newly diagnosed HNSCC patients. Two control groups, including 25 non-smokers and 64 smokers, were studied for comparison. A total of 821 serum samples collected over a twenty-four month period were analyzed by the MPS-H radioimmunoassay. RESULTS: HNSCC, non-smokers, and smokers had average MPS-H values of 41.5 ng/mL, 10.2 ng/mL, and 12.8 ng/mL, respectively (p = 0.0001). CONCLUSION: We conclude that MPS-1 and MPS-1-like proteins are elevated in patients with HNSCC, and that MPS-H appears to be a promising marker of presence of disease and response to treatment in HNSCC patients

Ternary organic photodetectors based on pseudo–binaries nonfullerene–based acceptors

The addition of a third component to a donor:acceptor blend is a powerful tool to enhance the power conversion efficiency of organic solar cells. Featuring a similar operating mechanism, organic photodetectors are also expected to benefit from this approach. Here, we fabricated ternary organic photodetectors, based on a polymer donor and two nonfullerene acceptors, resulting in a low dark current of 0.42 nA cm−2 at −2 V and a broadband specific detectivity of 1012 Jones. We found that exciton recombination in the binary blend is reduced in ternary devices due to the formation of a pseudo-binary microstructure with mixed donor–acceptor phases. With this approach a wide range of intermediate open-circuit voltages is accessible, without sacrificing light-to-current conversion. This results in ternary organic photodetector (TOPD) with improved Responsivity values in the near-infrared. Moreover, morphology analyses reveal that TOPD devices showed improved microstructure ordering and consequentially higher charge carrier mobilities compared to the reference devices

Surface roughness in XeF2 etching of a-Si/c-Si(100)

Single wavelength ellipsometry and at. force microscopy (AFM) were applied in a well-calibrated beam-etching expt. to characterize the dynamics of surface roughening induced by chem. etching of a .apprx.12 nm amorphous Si (a-Si) top layer and the underlying cryst. Si (c-Si) bulk. In both the initial and final phase of etching, where either only a-Si or only c-Si is exposed to the XeF2 flux, we observe a similar evolution of the surface roughness as a function of the XeF2 dose proportional to D(XeF2)b with b~0.2. In the transition region from the pure amorphous to the pure cryst. silicon layer, we observe a strong anomalous increase of the surface roughness proportional to D(XeF2)b with b~1.5. Not only the growth rate of the roughness increases sharply in this phase, also the surface morphol. temporarily changes to a structure that suggests a cusp-like shape. The remaining a-Si patches on the surface act effectively as a capping layer which causes the growth of deep trenches in the c-Si. The ellipsometry data on the roughness are corroborated by the AFM results, by equating the thickness of the rough layer to 6 s, with s the root-mean-square variation of the AFM's distribution function of height differences. In the AFM data, the anomalous behavior is reflected in a too small value of s which again suggests narrow and deep surface features that cannot be tracked by the AFM tip. The final phase morphol. is characterized by an effective increase in surface area by a factor of two, as derived from a simple bilayer model of the reaction layer, using the exptl. etch rate as input. We obtain a local reaction layer thickness of 1.5 monolayer consistent with the 1.7 ML value of Lo et al. [Lo et al., Phys. Rev. B 47, 648 (1993)] that is also independent of surface roughness. [on SciFinder (R)

Boundary conditions at a fluid - solid interface

We study the boundary conditions at a fluid-solid interface using molecular dynamics simulations covering a broad range of fluid-solid interactions and fluid densities, and both simple and chain-molecule fluids. The slip length is shown to be independent of the type of flow, but rather is related to the fluid organization near the solid, as governed by the fluid-solid molecular interactions.Comment: REVtex, to appear in Physical Review Letter

Very high rotational frequencies and band termination in 73Br

Rotational bands in 73Br have been investigated up to spins of 65/2 using the EUROBALL III spectrometer. One of the negative-parity bands displays the highest rotational frequency 1.85 MeV reported to date in nuclei with mass number greater than 25. At high frequencies, the experimental dynamic moment of inertia for all bands decrease to very low values, indicating a loss of collectivity. The bands are described in the configuration-dependent cranked Nilsson-Strutinsky model. The calculations indicate that one of the negative-parity bands is observed up to its terminating single-particle state at spin 63/2. This result establishes the first band termination case in the A = 70 mass region.Comment: 6 pages, 6 figures, submitted to Phys. Rev. C as a Rapid Communicatio

Quantum teleportation and entanglement swapping with linear optics logic gates

We report on the usage of a linear optics phase gate for distinguishing all four Bell states simultaneously in a quantum teleportation and entanglement swapping protocol. This is demonstrated by full state tomography of the one and two qubit output states of the two protocols, yielding average state fidelities of about 0.83 and 0.77, respectively. In addition, the performance of the teleportation channel is characterised by quantum process tomography. The non classical properties of the entanglement swapping output states are further confirmed by the violation of a CHSH-type Bell inequality of 2.14 on average.Comment: 11 pages, 3 figure

Shape coexistence at the proton drip-line: First identification of excited states in 180Pb

Excited states in the extremely neutron-deficient nucleus, 180Pb, have been identified for the first time using the JUROGAM II array in conjunction with the RITU recoil separator at the Accelerator Laboratory of the University of Jyvaskyla. This study lies at the limit of what is presently achievable with in-beam spectroscopy, with an estimated cross-section of only 10 nb for the 92Mo(90Zr,2n)180Pb reaction. A continuation of the trend observed in 182Pb and 184Pb is seen, where the prolate minimum continues to rise beyond the N=104 mid-shell with respect to the spherical ground state. Beyond mean-field calculations are in reasonable correspondence with the trends deduced from experiment.Comment: 5 pages, 4 figures, submitted to Phys.Rev.