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To compare 6 airway-management devices in 3 isolation scenarios regarding their effect on airway management: portable isolation unit (PIU), personal protective equipment (PPE), and standard protection measures
In total, 30 anesthesiologists working in emergency medical services performed airway management on mannequins in 3 isolation settings using 6 different airway management devices (in random order): (1) standard Macintosh laryngoscope; (2) Airtraq SP-video-laryngoscope; (3) i-gel; (4) LMA-Fastrach; (5) Ambu fiberoptic-aScope; and (6) Melker cricothyrotomy-set. Each was assessed regarding time-to-ventilate (primary outcome) and rating of difficulty handling the device.
In 86% (standard protection) and 85% (PPE) of attempts, airway management was achieved in <60 seconds, irrespective of the device used. In the PIU setting, only 69% of attempts succeeded within this time frame (P<.05). Median time-to-ventilate was shorter for standard protection (23 seconds) and PPE (25 seconds) compared to the PIU (38 seconds; P<.001). In the PIU setting, the fiberscope took the longest (median, 170 seconds), while i-gel was the quickest (median, 13 seconds). The rating of difficulty (visual analogue scale [VAS], 0–100) differed significantly between the isolation scenarios: Airway management was most difficult with PIU (VAS, 76), followed by PPE (VAS, 35), and standard protection (VAS, 9) (P<.01).
Wearing PPE produced similar times-to-ventilate as standard protection among anesthesiologists, but it was subjectively rated more difficult. The portable isolation unit permitted acceptable times-to-ventilate when excluding fiberscope and cricothyrotomy. Supraglottic airway devices allowed the fastest airway management in all isolation scenarios, thus being highly recommendable if a portable isolation unit is used and emergency airway management becomes necessary.
The observational program “Deep spectral survey of the selected sky areas” on the 6-meter telescope is described. Preliminary results for the central part of field SA57 are discussed. The spectrum of a QS0 with probable redshift z=3.87 is presented. The number of quasars per sq. degree is estimated to be 470–675 to B < 23 mag., which gives the same slope in the increasing number of QSOs with magnitude as in brighter samples.
Two independent fields of 14′ × 14′ south east of M82 and 7′ × 7′ in SA 57 were completely spectroscopicaly searched for quasars using the Multi Slit Field Spectrograph at the 6-meter telescope of the Academy of Sciences of the USSR (Dodonov, 1982).
I would like to give the first results of a survey programme for high redshift quasars and related objects on the Tautenburg-Schmidt plates. It is known that objective prism plates are very useful for detecting these objects. the smaller the dispersion of the spectra, the fainter are the objects that can be found. Our Schmidt correcting lens gives spectra with the dispersion of 2500 Å mm−1 at Hγ. the limiting magnitude is about 19m in the B range. At this very low dispersion reliable classification of the objects requires the extraction of all the information stored on the plate. That means that a quantitative evaluation should supplement visual insepction.
Deep CCD photometry and kinematical observations can be used to constrain the dynamical status of compact groups of galaxies. In the case of Hickson 90 the main interaction is taking place between NGC 7174 and NGC 7173 while NGC 7176 appears to be virtually undisturbed.
Efficient data compression needs analyzing functions to recognise the local resolution of the signal. They are provided by the wavelet concept. The optimal wavelet (best information concentration) is defined by the image model of the application. For the most common images in astronomy the H-transform is optimal (in the sense of Karhunen-Loeve transform). The role of the H-transform in 2-dimensional processing is the same as the Haar-transform in 1-dimension, but it is not the ‘2-dimensional Haar-transform’ found in text books.
This is the second Asiago blue objects field studied to determine the physical nature of ultraviolet excess objects (UVX) at high galactic latitudes using low dispersion objective prism plates. As the first of this series ( Abati 1982 )this work has a double aim:
1.to determine the proportions in the component populations of UVX objects selected by the two-colour method on Schmidt telescope plates;
2.to determine the surface density of quasars down to a limiting magnitude m = 18 mag.
Observations with HST WFPC-2 from 1994 to 1997 show a number of features which can be attributed to the surface (notably the large as-yet-unnamed bright region, several smaller bright areas and a number of dark regions). The delineation of these features in several datasets is presented. Other features are variable and are due to atmospheric phenomena: these include the total brightness of Titan (drop by 5% 1994-1997 at 350 nm; increase by 7% at 889 nm), the hemispheric north-south asymmetry, and the hint of a south polar hood.
Additionally, small variable features, apparently due to clouds, are documented. As well as variability from one year to the next, these show anomalous center-to-limb brightness behaviour, and a 673/940 nm color much bluer than the large surface feature, consistent with clouds in the troposphere.
Titan passed through southern summer solstice in late 2002, allowing an unprecedented view of summer seasonal effects. A set of images was acquired with the Hubble Space Telescope spanning the 0.25-2 μmspectral range. Among the effects seen were a rapidly changing hemispheric asymmetry and a polar hood that is visible at short wavelengths. The north-south asymmetry has reversed, returning Titans dominant visual feature to something like its Voyager-era state. The polar hood is spectrally different from the north-south asymmetry and is due to a mode of small particles. The amount of absorbing material in the polar hood cannot be uniquely constrained, but a lower limit can be derived by assuming that the absorber is the same as that found in the main haze (i.e., it is analogous to Titan tholin) and that the absorber is entirely above the main haze. The hood spectrum is consistent with about 4xl0_6g/cm2 of tholin-like material above the main haze south of 65 S. A larger amount of material mixed lower in the atmosphere cannot be ruled out. An upper limit to the particle radius of about 0.02 μmcan be determined by the lack of a bright polar hood in near-infrared methane band images. Considering time scales for removing material from the stratosphere leads to an estimate of summer polar mass production that is within a factor of five of published estimates of annual, global aerosol mass production. More detailed modeling of the observations is proceeding. The model includes the prediction of disk-resolved polarization based on particle characteristics. Comparisons to HST polarimetric images will provide new constraints on the properties of the northern, southern, and polar aerosols. Preliminary analysis of the polarimetry images shows the polarization is radial at all wavelengths (0.25-2 μm) and the magnitude of polarization peaks near 0.75 μm. The polarization is consistent with small particles, but is less than predicted by models of Pioneer 11 and Voyager 2 polarimetry.
Genetic variation in the gene encoding ZNF804A, a risk gene for schizophrenia, has been shown to affect brain functional endophenotypes of the disorder, while studies of white matter structure have been inconclusive.
We analysed effects of ZNF804A single nucleotide polymorphism rs1344706 on grey and white matter using voxel-based morphometry (VBM) in high-resolution T1-weighted magnetic resonance imaging scans of 62 schizophrenia patients and 54 matched healthy controls.
We found a significant (p < 0.05, family-wise error corrected for multiple comparisons) interaction effect of diagnostic group x genotype for local grey matter in the left orbitofrontal and right and left lateral temporal cortices, where patients and controls showed diverging effects of genotype. Analysing the groups separately (at p < 0.001, uncorrected), variation in rs1344706 showed effects on brain structure within the schizophrenia patients in several areas including the left and right inferior temporal, right supramarginal/superior temporal, right and left inferior frontal, left frontopolar, right and left dorsolateral/ventrolateral prefrontal cortices, and the right thalamus, as well as effects within the healthy controls in left lateral temporal, right anterior insula and left orbitofrontal cortical areas. We did not find effects of genotype of regional white matter in either of the two cohorts.
Our findings demonstrate effects of ZNF804A genetic variation on brain structure, with diverging regional effects in schizophrenia patients and healthy controls in frontal and temporal brain areas. These effects, however, might be dependent on the impact of other (genetic or non-genetic) disease factors.
Strabismus represents a complex oculomotor disorder characterized by the deviation of one or both eyes and poor vision. A more sophisticated understanding of the genetic liability of strabismus is required to guide searches for associated molecular variants. In this classical twin study of 1,462 twin pairs, we examined the relative influence of genes and environment in comitant strabismus, and the degree to which these influences can be explained by factors in common with refractive error. Participants were examined for the presence of latent (‘phoria’) and manifest (‘tropia’) strabismus using cover–uncover and alternate cover tests. Two phenotypes were distinguished: eso-deviation (esophoria and esotropia) and exo-deviation (exophoria and exotropia). Structural equation modeling was subsequently employed to partition the observed phenotypic variation in the twin data into specific variance components. The prevalence of eso-deviation and exo-deviation was 8.6% and 20.7%, respectively. For eso-deviation, the polychoric correlation was significantly greater in monozygotic (MZ) (r = 0.65) compared to dizygotic (DZ) twin pairs (r = 0.33), suggesting a genetic role (p = .003). There was no significant difference in polychoric correlation between MZ (r = 0.55) and DZ twin pairs (r = 0.53) for exo-deviation (p = .86), implying that genetic factors do not play a significant role in the etiology of exo-deviation. The heritability of an eso-deviation was 0.64 (95% CI 0.50–0.75). The additive genetic correlation for eso-deviation and refractive error was 0.13 and the bivariate heritability (i.e., shared variance) was less than 1%, suggesting negligible shared genetic effect. This study documents a substantial heritability of 64% for eso-deviation, yet no corresponding heritability for exo-deviation, suggesting that the genetic contribution to strabismus may be specific to eso-deviation. Future studies are now needed to identify the genes associated with eso-deviation and unravel their mechanisms of action.
We report a study of InGaN and InAlN epilayers grown on GaN/Sapphire substrates by microfocused three-dimensional X-ray Reciprocal Space Mapping (RSM). The analysis of the full volume of reciprocal space, while probing samples on the microscale with a focused X-ray beam, allows us to gain uniquely valuable information about the microstructure of III-N alloy epilayers. It is found that “seed” InGaN mosaic nanocrystallites are twisted with respect to the ensemble average and strain free. This indicates that the growth of InGaN epilayers follows the Volmer-Weber mechanism with nucleation of “seeds” on strain fields generated by the a-type dislocations which are responsible for the twist of underlying GaN mosaic blocks. In the case of InAlN epilayer formation of composition gradient was observed at the beginning of the epitaxial growth.
We examined the light variations of AGB variables of the two Local Group members NGC 147 and NGC 185. A photometric monitoring in the i-band was carried out with the Nordic Optical Telescope at La Palma over ≈ 2.5 yrs resulting in roughly 35 data points for the period analysis. We found 513 long period variables (LPVs) in NGC 185 and 213 LPVs in NGC 147. Additional single-epoch Ks-band photometry was obtained for 387 (NGC 185, 323 with periods) and 182 (NGC 147, 147 with periods) LPVs, respectively. For a large fraction of these stars we also have an indication of the atmospheric chemistry (carbon- or oxygen-rich) from narrow band photometry (see Nowotny et al. 2003). The resulting Ks − logP diagrams for both systems show a well populated sequence of fundamental mode pulsators (sequence C, cf. Ita et al. 2004). In NGC 185 we also see a number of LPVs pulsating in the first overtone mode (sequence C’). Interestingly, such stars are missing in NGC 147. We speculate that this lack of shorter period variables in NGC 147 could originate from a difference in the star formation history (SFH) of the two galaxies, with NGC 147 containing a smaller population of intermediate-age stars.
The evolution of preferred orientations during processing appears to be of significant importance for the use of γ titanium aluminide alloys, since the desired lamellar microstructures exhibit a strong anisotropy of mechanical properties. As texture evolution certainly is dependent on several factors, involving deformation properties, recrystallization kinetics and particularly the phase constitution, different processing temperatures were investigated. By comparing the results it is indicated that the determined textures can be understood by the deformation modes of the dominating phase at hot-working temperature and the subsequent phase transformations.
Thin films of the orthorhombic perovskite GdAlO3 were grown on R-plane sapphire single crystals. Two different film growth methods were used, viz. (i) a chemical reaction of a Gd-O plasma with the sapphire crystals, and (ii) the reactive radio frequency (r.f.) sputtering of a GdAlO3 target. Subsequently, YBa2Cu3O7-δ (YBCO) films were deposited onto the GdAlO3 buffer by pulsed laser deposition (PLD). The GdAlO3 and YBCO films were investigated by Xray diffraction pole figure analysis and transmission electron microscopy (TEM), including highresolution transmission electron microscopy of cross sections. Independent of the deposition method the GdAlO3 films grew according to the nearly equivalent orientation relationships The GdAlO3 grains are additionally tilted by angles up to ± 3° around the sapphire [11.1] axis. On top of these buffer layers the YBCO films grew with c-orientation and with an in-plane rotation of 45°. YBCO films of 200 nm thickness on GdAlO3 buffer layers with a thickness of 10 to 20 nm showed a Tc > 87 K and a jc(77 K) > 3×106 A/cm2.
A knowledge of the structural behavior of molecules confined in thin liquid films and the way in which they differ from bulk behavior is of great importance to a variety of technological applications. We discuss X-ray scattering studies of the conformation of liquid polymer wetting layers on laterally structured substrates in order to test theories of the conformality of the wetting layer to the substrate. Recent work on guided X-ray beams confined to the thin film opens up the possibility of detailed studies of ordering phenomena in molecular layers adjacent to solid surfaces. Recent experiments are discussed.
Consolidation of continuous fiber-reinforced titanium aluminide matrix composites (TMC) by the foil/fiber/foil method has traditionally taken an empirical approach utilizing processing cycles derived by simple trial and error. In an effort to reduce the empirical nature of producing TMC, a simple but effective analytical approach is employed. This approach analyzes the effect of fiber and foil geometries on consolidation parameters by combining a physical constitutive creep model with computational methods of interpreting raw materials characterization data. Examples of SCS-6/super a2(Ti-25Al-10Nb-3Mo-lV) and Saphikon/γ-TiAl composites consolidation are discussed by comparing the model predictions with equivalent validation specimen microstructures.