Instrumentierung fuer BESSY II und temperaturprogrammierte Desorption von CO, NO und Wasser von (100)-Einkristallspaltflaechen der Metalloxide NiO und MgO

Fuer das Spektromikroskop SMART wurde eine Praeparationskammer und ein trotz seitlichen Zuges auf 2 #mu#m stabiles Schwingungsdaempfungssystem zur Verfuegung gestellt. In Tandemaufstellung mit dem SMART bei BESSY wurde ein Spektrometersystem mit hochaufloesendem Energieanalysator, Partial-Yield-Detektor, Fluoreszenzdetektor, Probenpraeparation sowie Heliumkuehlung aufgebaut. XPS-Messungen an Tantal-Deponaten auf Al_2O_3/NiAl(110)-Filmen zeigen, dass, waehrend dicke Filme oxidieren, Submonolagen inert sind. Erstmalig wurde die temperaturprogrammierte Desorption (TPD, TDS) von CO, NO und H_2O einschliesslich der Multilagendesorptionen von UHV-gespaltenen MgO und NiO-Einkristallen untersucht. Dafuer wurde eine UHV-Apparatur und eine Heizrampenregelung entwickelt.For the spectromicroscope SMART, an independent preparation chamber and a vibration isolation system accurate to 2 #mu#m in spite of lateral forces have been set up. Placed in a row with the SMART at BESSY, a spectrometer system has been built. It contains a high-resolution energy analyser, a partial-yield- and a fluorescence detector, sample preparation tools and helium cooling. XPS investigations on tantalum deposits on Al_2O_3/NiAl(110) thin films revealed that submonolayer deposits show no oxidation although thicker films do. For the first time, temperature programmed desorption (TPD, TDS) of CO, NO, and H_2O has been investigated including the respective multilayer desorptions on UHV-cleaved single crystal MgO and NiO-surfaces.SIGLEAvailable from: http://www.iwi-iuk.org/dienste/TheO/ / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

TDS study of the bonding of CO and NO to vacuum-cleaved NiO(100)

Using thermal desorption spectroscopy (TDS) we have determined the adsorption enthalpies of NO and CO on a NiO(100) surface obtained by cleavage of a NiO single crystal rod under ultra-high vacuum (UHV) conditions. The TDS data have been evaluated using the leading edge method and complete analysis, yielding values of 0.30±0.04 and 0.57±0.04 eV for the heats of adsorption of CO and NO, respectively, in the low coverage regime. These values decrease with increasing coverage down to the respective multilayer values. The results obtained experimentally are different from the theoretical ones, in that the experimental values are systematically larger. This is possibly due to the influence of the Ni3d electrons as concluded from a comparison with TDS data for CO on vacuum-cleaved MgO(100). The adsorbate bonding energies obtained for vacuum-cleaved NiO(100) are in good agreement with values for thin NiO(100) films deduced from thermal-desorption studies and infrared investigations

Thermodesorption of CO and NO from Vacuum-Cleaved NiO(100) and MgO(100)

This paper presents experimental data on the bonding of CO and NO to vacuum-cleaved MgO(100) and NiO(100) and compares them with theoretical results. In the case of CO and NO on NiO(100) we find that the bonding energies obtained for the vacuum-cleaved single crystals agree well with results of recent studies on thin NiO(100) films grown by oxidation of Ni(100) whereas they are at variance with theoretical results. On the other hand, for CO on MgO(100) the experimental data fit well to recent theoretical studies while they contradict studies of adsorption on MgO(100) films grown on Mo(100). The experimentally determined values for the adsorption energies are 0.30 and 0.57 eV for adsorption of CO and NO on NiO(100), respectively, and 0.14 and 0.22 eV for adsorption on MgO(100). We suggest that the stronger bonding to NiO(100) as compared to MgO(100) is due to the influence of the 3d electrons of NiO

Hybrid Treatment For Correction Of Pseudoaneurysm After Surgical Treatment Of Aortic Coarctation [tratamento Híbrido Para Correção De Pseudoaneurisma Após Tratamento Cirúrgico De Coarctação Aórtica]

The need for a new surgical procedure for correction of postoperative pseudoaneurysm of aortic coarctation makes the procedure especially challenging for the surgeon.ta abstract.274642644Yazar, O., Budts, W., Maleux, G., Houthoofd, S., Daenens, K., Fourneau, I., Thoracic endovascular aortic repair for treatment of late complications after aortic coarctation repair (2011) Ann Vasc Surg., 25 (8), pp. 1005-1011Oliver, J.M., Gallego, P., Gonzalez, A., Aroca, A., Bret, M., Mesa, J.M., Risk factors for aortic complications in adults with coarctation of the aorta (2004) J Am Coll Cardiol, 44 (8), pp. 1641-1647Hörmann, M., Pavlidis, D., Brunkwall, J., Gawenda, M., Long-term results of endovascular aortic repair for thoracic pseudoaneurysms after previous surgical coarctation repair (2011) Interact Cardiovasc Thorac Surg., 13 (4), pp. 401-404Crafoord, C., Nylin, G., Congenital coarctation of the aorta and its surgical treatment (1945) J Thorac Surg., 14, pp. 347-361Carr, J.A., The results of catheter-based therapy compared with surgical repair of adult aortic coarctation (2006) J Am Coll Cardiol., 47 (6), pp. 1101-1107Ingrund, J.C., Nasser, F., Jesus-Silva, S.G., Limaco, R.P., Galastri, F.L., Burihan, M.C., Tratamento híbrido das doenças complexas da aorta torácica (2010) Rev Bras Cir Cardiovasc., 25 (3), pp. 303-31

SMART: An Aberration-Corrected XPEEM/LEEM with Energy Filter

A new UHV spectroscopic X-ray photoelectron emission and low energy electron microscope is presently under construction for the installation at the PM-6 soft X-ray undulator beamline at BESSY II. Using a combination of a sophisticated magnetic beam splitter and an electrostatic tetrode mirror, the spherical and chromatic aberrations of the objective lens are corrected and thus the lateral resolution and sensitivity of the instrument improved. In addition a corrected imaging energy filter (a so-called omega filter) allows high spectral resolution (ΔE=0.1 eV) in the photoemission modes and back-ground suppression in LEEM and small-spot LEED modes. The theoretical prediction for the lateral resolution is 5 Å; a realistic goal is about 2 nm. Thus, a variety of electron spectroscopies (XAS, XPS, UPS, XAES) and electron diffraction (LEED, LEEM) or reflection techniques (MEM) will be available with spatial resolution unreached so far

SMART: a planned ultrahigh-resolution spectromicroscope for BESSY II

A new UHV spectromicroscope called SMART (spectromicroscope for all relevant techniques) is currently under construction for a soft X-ray undulator beamline at BESSY II. The instrument consists of a plane-grating monochromator with an aspherical focusing mirror and an ultrahigh-resolution, low-energy electron microscope containing an energy filter. It can be used as a photoemission microscope for a variety of electron spectroscopies (XAS, XPS, UPS, XAES) and has a calculated spatial resolution of better than 1 nm. A maximum energy resolution of about 0.1 eV will be provided by a corrected omega filter. The high lateral resolution of the electron microscope will be achieved through the correction of the chromatic and spherical aberrations of the objective lens by means of an electrostatic mirror in combination with a corrected magnetic beam separator. An additional electron source placed on the other side of the beam separator opposite the electrostatic mirror will also allow LEEM, MEM and small-spot LEED investigations to be carried out. The basic ideas, the various modes of operation and the electron optical design of the instrument are outlined

Cerebral oximetry during cardiac arrest: a multicenter study of neurologic outcomes and survival

OBJECTIVES: Cardiac arrest is associated with morbidity and mortality because of cerebral ischemia. Therefore, we tested the hypothesis that higher regional cerebral oxygenation during resuscitation is associated with improved return of spontaneous circulation, survival, and neurologic outcomes at hospital discharge. We further examined the validity of regional cerebral oxygenation as a test to predict these outcomes. DESIGN: Multicenter prospective study of in-hospital cardiac arrest. SETTING: Five medical centers in the United States and the United Kingdom. PATIENTS: Inclusion criteria are as follows: in-hospital cardiac arrest, age 18 years old or older, and prolonged cardiopulmonary resuscitation greater than or equal to 5 minutes. Patients were recruited consecutively during working hours between August 2011 and September 2014. Survival with a favorable neurologic outcome was defined as a cerebral performance category 1-2. INTERVENTIONS: Cerebral oximetry monitoring. MEASUREMENTS AND MAIN RESULTS: Among 504 in-hospital cardiac arrest events, 183 (36%) met inclusion criteria. Overall, 62 of 183 (33.9%) achieved return of spontaneous circulation, whereas 13 of 183 (7.1%) achieved cerebral performance category 1-2 at discharge. Higher mean ± SD regional cerebral oxygenation was associated with return of spontaneous circulation versus no return of spontaneous circulation (51.8% ± 11.2% vs 40.9% ± 12.3%) and cerebral performance category 1-2 versus cerebral performance category 3-5 (56.1% ± 10.0% vs 43.8% ± 12.8%) (both p < 0.001). Mean regional cerebral oxygenation during the last 5 minutes of cardiopulmonary resuscitation best predicted the return of spontaneous circulation (area under the curve, 0.76; 95% CI, 0.69-0.83); regional cerebral oxygenation greater than or equal to 25% provided 100% sensitivity (95% CI, 94-100) and 100% negative predictive value (95% CI, 79-100); regional cerebral oxygenation greater than or equal to 65% provided 99% specificity (95% CI, 95-100) and 93% positive predictive value (95% CI, 66-100) for return of spontaneous circulation. Time with regional cerebral oxygenation greater than 50% during cardiopulmonary resuscitation best predicted cerebral performance category 1-2 (area under the curve, 0.79; 95% CI, 0.70-0.88). Specifically, greater than or equal to 60% cardiopulmonary resuscitation time with regional cerebral oxygenation greater than 50% provided 77% sensitivity (95% CI,:46-95), 72% specificity (95% CI, 65-79), and 98% negative predictive value (95% CI, 93-100) for cerebral performance category 1-2. CONCLUSIONS: Cerebral oximetry allows real-time, noninvasive cerebral oxygenation monitoring during cardiopulmonary resuscitation. Higher cerebral oxygenation during cardiopulmonary resuscitation is associated with return of spontaneous circulation and neurologically favorable survival to hospital discharge. Achieving higher regional cerebral oxygenation during resuscitation may optimize the chances of cardiac arrest favorable outcomes