Zr65Cu17.5Ni10Al7.5 as well as Zr69.5Cu12Ni11Al7.5 belong to the best glass forming alloys known. Glass transition temperatures of melt-spun ribbons are 372 and 360 °C, respectively. TEM and x-ray analysis of samples annealed above the glass transition temperature exhibit the formation of quasicrystalline microstructures with small amounts of crystalline phases. The metastable icosahedral phase is primitive with a quasilattice constant a=0.253 nm; its composition as determined by EDX is close to Zr69.5Cu12Ni11Al7.5. In both glasses, growth of the quasicrystals has been observed to be time-dependent (r∝t1/2), thus indicating a diffusion controlled transformation.

The incorporation of NO into the surface of extracorporeal circuits reduces platelet consumption and eliminates the need for systemic heparinization in a rabbit model of extracorporeal circulation.

Increased abdominal pressure is common in intensive care unit patients. To investigate its impact on respiration and hemodynamics we applied intraabdominal pressure (aIAP) of 0 and 20 cm H 2 O (pneumoperitoneum) in seven pigs. The whole-lung computed tomography scan and a complete set of respiratory and hemodynamics variables were recorded both in healthy lung and after oleic acid (OA) injury. In healthy lung, aIAP 20 cm H 2 O significantly lowered the gas content, leaving the tissue content unchanged. In OAinjured lung at aIAP 0 cm H 2 O, the gas content significantly decreased compared with healthy lung. The excess tissue mass (edema) amounted to 30 Ϯ 24% of the original tissue weight (455 Ϯ 80 g). The edema was primarily distributed in the base regions and was not gravity dependent. Heart volume, central venous, pulmonary artery, wedge, and systemic arterial pressures significantly increased. At aIAP 20 cm H 2 O in OA-injured lung, the central venous and pulmonary artery pressures further increased. The gas content further decreased, and the excess tissue mass rose up to 103 Ϯ 37% (tissue weight 905 Ϯ 134 g), with homogeneous distribution along the cephalocaudal and sternovertebral axis. We conclude that in OAinjured lung, the increase of IAP increases the amount of edema.Keywords: intraabdominal pressure; acute respiratory distress syndrome; pulmonary edema; lung mechanics; computed tomography scanThe importance of intraabdominal pressure (IAP) in acute lung injury and acute respiratory distress syndrome has been recently suggested (1). For a long time any change in respiratory mechanics in patients with acute lung injury/acute respiratory distress syndrome was attributed to lung mechanics, whereas chest wall mechanics was assumed to be normal. However, few studies in which chest wall elastance was actually measured have showed that it was abnormal in a substantial proportion of patients with acute lung injury/acute respiratory distress syndrome (2-4). We (5) and others (6) have described different chest wall mechanics in patients with pulmonary and extrapulmonary acute respiratory distress syndrome, mainly due to different IAP values.However, apart from respiratory mechanics, the increased intrathoracic pressure caused by chest wall impairment may have important consequences on hemodynamics (7). We investigated the effect of changing IAP during controlled mechanical ventilation in healthy and diseased lungs. Surprisingly, the increase of IAP had an unexpected impact on lung edema, likely related to its formation and clearance. We wish to report our findings and METHODS(Additional details about Methods are provided in an online supplement.)The study group consisted of seven anesthetized and paralyzed domestic pigs (41 Ϯ 4 kg) ventilated throughout the experiment in supine position, with a Vt of 12 ml/kg, respiratory rate of 12-14 breaths/minute, positive end-expiratory pressure of 5 cm H 2 O, and Fi O 2 of 1.0. The animals were fully instrumented for hemodynamic monitoring (carotid artery, right atrium, mea...

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The rare case of a metal-triggered broad-band yellow emitter among inorganic-organic hybrid materials was achieved by in situ codoping of the novel imidazolate metal-organic framework ∞(3)[Ba(Im)2] with divalent europium. The emission maximum of this dense framework is in the center of the yellow gap of primary light-emitting diode phosphors. Up to 20% Eu2+ can be added to replace Ba2+ as connectivity centers without causing observable phase segregation. High-resolution energy-dispersive X-ray spectroscopy showed that incorporation of even 30% Eu2+ is possible on an atomic level, with 2-10% Eu2+ giving the peak quantum efficiency (QE = 0.32). The yellow emission can be triggered by two processes: direct excitation of Eu2+ and an antenna effect of the imidazolate linkers. The emission is fully europium-centered, involving 5d → 4f transitions, and depends on the imidazolate surroundings of the metal ions. The framework can be obtained by a solvent-free in situ approach starting from barium metal, europium metal, and a melt of imidazole in a redox reaction. Better homogeneity for the distribution of the luminescence centers was achieved by utilizing the hydrides BaH2 and EuH2 instead of the metals.

To cite this article: P-A Douissard et al 2012 JINST 7 P09016 View the article online for updates and enhancements. Related content Detection system for microimaging with neutrons S H Williams, A Hilger, N Kardjilov et al.-Characterisation of microfocused beam for synchrotron powder diffraction using a new X-ray camera C Thomas, J Potter, C C Tang et al.-Laminographic imaging using synchrotron radiation-challenges and opportunities Lukas Helfen, Feng Xu, Heikki Suhonen et al.-Recent citations Epitaxial growth of single crystalline film scintillating screens based on Eu3+ doped RAlO3 (R = Y, Lu, Gd, Tb) perovskites V. Gorbenko et al-Mixing instabilities during shearing of metals Mohsen Pouryazdan et al-A transmission and reflection coupled ultrasonic process tomography based on cylindrical miniaturized transducers using PVDF films J. Gu et al

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