Mixing and merging for spoken document retrieval

This paper describes a number of experiments that explo- red the issues surrounding the retrieval of spoken documents. Two such issues were examined. First, attempting to find the best use of speech recogniser output to produce the highest retrieval effectiveness. Second, investigating the potential problems of retrieving from a so-called "mi- xed collection", i.e. one that contains documents from both a speech recognition system (producing many errors) and from hand transcription (producing presumably near perfect documents). The result of the first part of the work found that merging the transcripts of multiple recognisers showed most promise. The investigation in the second part showed how the term weighting scheme used in a retrieval system was important in determining whether the system was affected detrimentally when retrieving from a mixed collection

Asymmetric field dependence of magnetoresistance in magnetic films

We study an asymmetric in field magnetoresistance that is frequently observed in magnetic films and, in particular, the odd longitudinal voltage peaks that appear during magnetization reversal in ferromagnetic films, with out-of-plane magnetic anisotropy. We argue that the anomalous signals result from small variation of magnetization and Hall resistivity along the sample. Experimental data can be well described by a simple circuit model, the latter being supported by analytic and numerical calculations of current and electric field distribution in films with a gradual variation of the magnetization and Hall resistance.Comment: 7 pages, 5 figures, to be published in Phys. Rev.

Appropriate placement of intubation depth marks in a new cuffed paediatric tracheal tube

Background. The aim of this study was to evaluate the appropriateness of intubation depth marks on the new Microcuff paediatric tracheal tube. Methods. With local Institutional Ethics Committee approval and informed parental consent, we included patients from birth (weighing ≥3 kg) to 16 yr who were undergoing general anaesthesia requiring orotracheal intubation. Tracheal intubation was performed using direct laryngoscopy, the intubation depth mark was placed between the vocal cords, and the tube was taped to the lateral corner of the mouth. The distance between the tube tip and the tracheal carina was assessed by flexible bronchoscopy with the patients in supine, and their head in neutral positions. Tube sizes were selected according to the formula: internal diameter (ID; mm)=(age/4)+3.5 in children ≥2 yr. In full-term newborns (≥3 kg) to less than 1 yr ID 3.0 mm tubes were used and in children from 1 to less than 2 yr ID 3.5 mm tubes were used. Endoscopic examination was performed in 50 size ID 3.0 mm tubes, and in 25 tubes of each tube size from ID 3.5 to 7.0 mm. Tracheal length and percentage of the trachea to which the tube tip was advanced were calculated. Results. 250 patients were studied (105 girls, 145 boys). The distance from the tube tip to the carina ranged from 1.4 cm in a 2-month-old infant (ID 3.0 mm) to 7.7 cm in a 14-yr-old boy (ID 7.0 mm). Mean tube insertion into the trachea was 53.2% (6.3) of tracheal length with a minimum of 40% and a maximum of 67.6%. Conclusions. The insertion depth marks of the new Microcuff paediatric tracheal tube allow adequate placing of the tracheal tube with a cuff-free subglottic zone and without the risk for endobronchial intubation in children from birth to adolescenc

In-vivo assessment of in-vitro killing patterns of Pseudomonas aeruginosa

Time-kill curves of Pseudomonas aeruginosa exposed to gentamicin or ticarcilhn in vitro were correlated with time-kill curves obtained with various dosage schedules of the same study drugs in granulocytopenic mice. An instantaneous, fast and drug-dependent killing pattern was found in vitro with gentamicin. This pattern corresponded to bacterial killing in vivo which was clearly dependent on peak drug levels. In contrast, slow bacterial killing with little relationship to concentration was found in vitro with ticarcilhn and proved to correlate with an antibacterial effect in vivo seen at trough levels. We conclude that in-vitro time-kill curves of antimicrobial agents may be predictive for optimizing dosage regimens in viv

Correlation between the Extraordinary Hall Effect and Resistivity

We study the contribution of different types of scattering sources to the extraordinary Hall effect. Scattering by magnetic nano-particles embedded in normal-metal matrix, insulating impurities in magnetic matrix, surface scattering and temperature dependent scattering are experimentally tested. Our new data, as well as previously published results on a variety of materials, are fairly interpreted by a simple modification of the skew scattering model

Shortcomings of cuffed paediatric tracheal tubes†

Background. The goal of this investigation was to evaluate adequacy of the design of readily available paediatric cuffed tracheal tubes (CPTT). Methods. In 15 series of cuffed (11) and uncuffed (four) paediatric tracheal tubes (ID: 2.5-7.0 mm) from four different manufacturers the following dimensions were measured: outer diameter of the tube, position and largest diameter of the tube cuff inflated at 20 cm H2O and position of depth markings and compared with age‐related dimensions. Results. Outer diameters for tubes with similar IDs varied markedly between manufacturers and between cuffed and uncuffed tracheal tubes from the same manufacturer. Cuff diameters at 20 cm H2O cuff pressure and cross‐sectional cuff area at 20 cm H2O cuff pressure did not always cover maximal internal age‐related tracheal diameters and cross‐sectional areas. Placing the tube tip in the mid‐trachea, the cuffs of cuffed tubes with ID 3.0, 4.0, or 5.0 mm would become positioned within the larynx. If the cuffs were placed 1 cm below the cricoid level, many of the tube tips would be dangerously deep within the trachea. Only five of the 11 cuffed tubes had a depth marking. In many of these tubes the distances from depth marking to tube tip were greater than the age‐related minimal tracheal length. Conclusion. Most cuffed paediatric tracheal tubes are poorly designed, in particular the smaller sizes. A better design of cuffed tubes with a short high‐volume, low‐pressure cuff, cuff‐free subglottic space and adequately placed depth markings are urgently needed. Br J Anaesth 2004; 92: 78-8

Progressive Star Bursts and High Velocities in the Infrared Luminous, Colliding Galaxy Arp 118

In this paper we demonstrate for the first time the connection between the spatial and temporal progression of star formation and the changing locations of the very dense regions in the gas of a massive disk galaxy (NGC 1144) in the aftermath of its collision with a massive elliptical (NGC 1143). These two galaxies form the combined object Arp 118, a collisional ring galaxy system. The results of 3D, time-dependent, numerical simulations of the behavior of the gas, stars, and dark matter of a disk galaxy and the stars and dark matter in an elliptical during a collision are compared with multiwavelength observations of Arp 118. The collision that took place approximately 22 Myr ago generated a strong, non-linear density wave in the stars and gas in the disk of NGC 1144, causing the gas to became clumped on a large scale. This wave produced a series of superstarclusters along arcs and rings that emanate from the central point of impact in the disk. The locations of these star forming regions match those of the regions of increased gas density predicted the time sequence of models. The models also predict the large velocity gradients observed across the disk of NGC 1144. These are due to the rapid radial outflow of gas coupled to large azimuthal velocities in the expanding ring, caused by the impact of the massive intruder.Comment: 12 pages in document, and 8 figures (figures are separate from the document's file); Submitted to Astrophysical Journal Letter

Star Formation Across the Taffy Bridge: UGC 12914/15

We present BIMA two-field mosaic CO(1-0) images of the Taffy galaxies (UGC 12914/15), which show the distinct taffy-like radio continuum emission bridging the two spiral disks. Large amounts of molecular gas (1.4 x 10^{10} Msun, using the standard Galactic CO-to-H$_2$ conversion applicable to Galactic disk giant molecular clouds [GMCs]) were clearly detected throughout the taffy bridge between the two galaxies, which, as in the more extreme case of HI, presumably results from a head-on collision between the two galaxies. The highest CO concentration between the two galaxies corresponds to the H_alpha source in the taffy bridge near the intruder galaxy UGC 12915. This HII region is also associated with the strongest source of radio continuum in the bridge, and shows both morphological and kinematic connections to UGC 12915. The overall CO distribution of the entire system agrees well with that of the radio continuum emission, particularly in the taffy bridge. This argues for the star formation origin of a significant portion of the radio continuum emission. Compared to the HI morphology and kinematics, which are strongly distorted owing to the high-speed collision, CO better defines the orbital geometry and impact parameter of the interaction, as well as the disk properties (e.g., rotation, orientation) of the progenitor galaxies. Based on the 20cm-to-CO ratio maps, we conclude that the starburst sites are primarily located in UGC 12915 and the H_alpha source in the bridge and show that the molecular gas in the taffy bridge is forming into stars with star formation efficiency comparable to that of the target galaxy UGC 12914 and similar to that in the Galactic disk.Comment: Minor typo/style corrections to match with the published version (AJ, Nov. issue). A single .ps.gz file of the entire paper can be downloaded from http://spider.ipac.caltech.edu/staff/gao/Taffy/all.ps.g

Chandra Observations of Extended X-ray Emission in Arp 220

We resolve the extended X-ray emission from the prototypical ultraluminous infrared galaxy Arp 220. Extended, faint edge-brightened, soft X-ray lobes outside the optical galaxy are observed to a distance of 10 to 15 kpc on each side of the nuclear region. Bright plumes inside the optical isophotes coincide with the optical line emission and extend 11 kpc from end to end across the nucleus. The data for the plumes cannot be fit by a single temperature plasma, and display a range of temperatures from 0.2 to 1 keV. The plumes emerge from bright, diffuse circumnuclear emission in the inner 3 kpc centered on the Halpha peak, which is displaced from the radio nuclei. There is a close morphological correspondence between the Halpha and soft X-ray emission on all spatial scales. We interpret the plumes as a starburst-driven superwind, and discuss two interpretations of the emission from the lobes in the context of simulations of the merger dynamics of Arp 220.Comment: Accepted for publication in ApJ; see also astro-ph/0208477 (Paper 1