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Cardiac catheterisation is commonly used for diagnosis and therapeutic interventions in paediatric cardiology. The inherent risk of the procedure can result in unanticipated admissions to critical care. Our goals were to provide a qualitative description of characteristics and evaluation of children admitted unexpectedly to the cardiac critical care unit (CCCU).
A retrospective single centre review of cardiac catheterisation procedures was done between 1 January, 2003 and 30 April, 2013.
Of 9336 cardiac catheterisations performed, 146 (1.6%) were admitted from the catheterisation laboratory to the CCCU and met inclusion criteria. Of these 146 patients, 117 (1.3%) met criteria for unexpected admission and 29 (0.3%) were planned admissions. The majority admitted unexpectedly were below 1 year of age without co-morbidity aside from heart disease. Patients with planned admissions were significantly more likely to have single ventricle physiology, undergoing angiography or transferred for observation. Most unplanned admissions were triggered by interventional catheterisations or procedure-related complications. Patients received mechanical ventilation as the main CCCU management. Eighteen patients needed either cardiopulmonary resuscitation and/or extracorporeal membrane oxygenation during their catheterisation. About 106/117 (90.6%) patients survived to hospital discharge with no deaths in the planned admission group.
Admission to CCCU following cardiac catheterisation was uncommon and tended to occur in younger children undergoing interventional procedures. Outcomes did not differ between patients experiencing planned and unplanned CCCU admission. Ongoing development of risk stratification tools may help to decrease unplanned CCCU admissions. Further studies are needed to determine whether unplanned admission following paediatric cardiac catheterisation should be utilised as a quality indicator.
Our experience using Mo Kα radiation in coal related research indicates that minerals can be detected and quantitatively measured at the 0.2% level in an amorphous substance such as coal. Since the linear absorption coefficient for most elements is about a factor of eight lower for Mo radiation than it is for Cu radiation, the matrix affect is greatly reduced and the intensity is a more linear function of concentration.
Although there is considerable overlapping of peaks when complex mixtures are analyzed using Mo radiation, the use of second derivative techniques to locate peaks, and least squares techniques to fit peaks can resolve many of these problems. The reduced time needed to collect a diffraction pattern, and the increased intensity obtained more than compensate for the extra computer time needed to analyze the data.
Superluminal motions were first seen in 3C 120 between 1972.5 and 1974.4 (Seielstad et al. 1979 and references therein). Between 1975 and 1980, the source was monitored along with 3C 273 and 3C 345 by the Caltech group. One reasonably clear episode of expansion was seen in 1979 (Walker et al. 1982) but, for most of the time, the source evolution was so rapid that it was difficult to relate the structures seen at successive epochs.
We present VLBI and VLA maps of the superluminal radio source 3C 120 (z = 0.03). The 18 cm VLBI maps shown in Figures 1 and 2c were constructed from a 14 station VLBI observation on 10, 11 October 1982. The map in Figure 1 is at full spatial resolution. The Figure 2c map was made from a uv-tapered data set and shows the extended emission. The VLBI maps show a jet ~175 pc long with distinct knots and bends (H0 = 55 kms−1 Mpc−1). The 18 cm jet smoothly connects to the 6 cm superluminal jet (Figure 2d). The VLBI jet remains well collimated through several bends and only begins to spread out 100 pc beyond the core. At 175 pc from the core, the jet is wide and weak, and disappears into the under-sampled region of the uv-plane (< 2(10)6 λ's).
3C236 is the largest radio source known. It has a 39 arcmin double structure (3.0 Mpc, Ho=75 kms−1 Mpc−1) in which the SE lobe is narrow and edge-brightened and the NW lobe more diffuse and centre-brightened (Barthel et al., 1985). About half the flux density comes from a steep spectrum (α = −0.7) radio core of overall size 1.3 arcsec (2.2 kpc) located in the centre of a 17m elliptical galaxy with redshift 0.0988.
The well known jet in M87 (Virgo A) has been extensively studied in the radio regime using conventional arrays with resultant resolutions in the range 0.22–1 arcsecond. We present here the results of a VLBI experiment to map the jet over its entire length (30 arcseconds) to high resolution. The observations were made in April 1984 at 1.67 GHz with a ‘World Array’ containing 18 VLBI telescopes. In addition, simultaneous observations were performed with the 6 station MERLIN array.
3C 120 is a nearby radio galaxy (z = 0.033) that shows superluminal motions in its radio jet within one parsec of the nucleus. The apparent velocities of the moving features are approximately 1.5 mas/yr. This object is of particular interest because it is clearly identified with an N-type galaxy, unlike all other superluminal radio sources which are only seen in quasars and BL Lac objects. Because of the close proximity of 3C 120, we have been able to make a series of VLBI and VLA images at stepped resolutions, and thereby map the radio jet continuously from the radio nucleus (0.5 h−1 parsec) into the diffuse 400 h−1 kpc structure.
The jet in the superluminal source 3C 120 has been observed on all scales from under a parsec to about 100 kpc. The jet brightness decays rather smoothly with core distance, indicating that the basic characteristics of the jet are established on parsec or smaller scales and evolve simply with distance.
The IceCube Neutrino Observatory was constructed at the South Pole during the 2004/05 to 2010/11 austral summer seasons. IceCube transforms 1 km3 of Antarctic ice into an astrophysical particle detector composed of 86 cables (strings) of optical sensors buried deep beneath the surface. Each string required drilling a borehole ∼60 cm in diameter to a depth of 2500 m. The 5 MW Enhanced Hot Water Drill was designed and built specifically for this task, capable of producing the required boreholes at a rate of one hole per 48 hours. Hot-water drilling on this scale presented unique challenges and was rich in lessons learned, yielding a collection of notable developments and takeaways (e.g. fuel-saving measures, thermal modeling, firn drilling and closed-loop computer control). Descriptions of system functionality and of lessons learned from IceCube drilling are presented.
IceCube, a cubic-kilometer neutrino detector, was built at the South Pole using a hot-water drill system. Deep holes were drilled into the Antarctic ice sheet and filled with highly sensitive optical instrumentation. For the hot-water drilling, a computer model was developed to predict the hole sizes and hole lifetimes during construction. The goal was to predict ultimate size and freezeback rates based on water flow rate and temperature, drill speed, ice temperature and ream parameters (for a secondary operation where hot water continues to flow as the drill is withdrawn). This model proved to be very successful. It increased confidence that the holes would remain open long enough after drilling to allow the deployment of the necessary instrumentation. It also allowed for a decrease, over the course of the project, in the amount of overdrilling that was used as a margin against a too-rapid freeze-in. This resulted in significant fuel savings.
Field measurements of water temperatures in two turbulent streams in interior Alaska have been made during periods of frazil-ice production. The measured equilibrium temperature of the water Te-0.005°C agrees with the value calculated from the electrical conductivity of the water. Average cooling rates of the streams during the summer-to-fall stream cooling period were on the order of several tenths of a degree per day with average surface heat losses of -5 to -18 W m−2. Just prior to a frazil-ice event, the water-cooling rates were -1 to -3 mK min−1 with surface heat losses of -47 to -140 M m−2Supercooling at the water surface of a stream prior to and during frazil-ice production does not exceed 0.2°C as shown by measurements of air-water temperature profiles and by radiometer measurements. Mater supercooling at the time of frazil-ice nucleation was <10 mK. These measurements show that frazil-ice nuclei in streams must be other ice particles, cold organic materials, cold soil particles, or a combination of these, that may be introduced into the stream by mass exchange processes at the air-water interface.
The maximum observed supercooling was ΔTm 40 mK. Two measured values for the residual supercooling were 3 and 9 mK. Frazil growth rates calculated from the observed values of supercooling show that, unless the period of residual supercooling is very long, most of the frazil-ice production during one night of supercooling occurred in the transient thermal period from the time of nucleation to the time that the water became residually supercooled.
Sinonasal undifferentiated carcinoma is a rare aggressive tumour arising from the Schneiderian epithelium lining the sinonasal tract. Although considered the cornerstone of therapy, surgical resection can only be performed in a limited number of patients. This report describes the experience of treating sinonasal undifferentiated carcinoma with a multimodality approach.
The treatment charts of sinonasal undifferentiated carcinoma patients treated at a tertiary care centre from 2004 to 2012 were retrospectively reviewed.
A total of 16 sinonasal undifferentiated carcinoma patients with a median age at diagnosis of 47.5 years (range 8–65 years) were included: 19 per cent had neck nodal metastasis at presentation. Four patients (25 per cent) underwent surgery: of these, two had post-operative radiotherapy, one had pre-operative radiotherapy and one had adjuvant chemotherapy alone. Six patients (38 per cent) received definitive radiotherapy: five had received neoadjuvant chemotherapy to reduce tumour size and help in radiotherapy planning, while four (25 per cent) received palliative radiotherapy. The median follow up was 10.4 months (range 1–42.5 months). The estimated median progression-free survival time was 29.3 months. One- and three-year progression-free survival rates were 77 per cent and 41 per cent, respectively.
Surgery is the best treatment option for sinonasal undifferentiated carcinoma, although most patients require post-operative radiotherapy for advanced disease and close tumour margins. Definitive radiotherapy with or without chemotherapy may be suitable for patients with inoperable locally advanced disease. Elective nodal irradiation to address the high nodal involvement rates should be considered to improve the survival rate.
We describe a space VLBI experiment involving an earth-orbiting satellite (SURFSAT) and simulated satellites, a space VLBI ground tracking station, an array of ground radio telescopes, and a space VLBI correlator. The purpose of this experiment was to provide as complete as possible an end-to-end simulation of space VLBI in preparation for the first space VLBI mission, VSOP, and in particular to test the most critical aspect of space VLBI, viz. the ability to generate a stable and accurate frequency standard (clock) for the orbiting VLBI element.
A variety of means, including forelimb proportions and shell bone histology have been used to infer the paleoecology of extinct turtles. However, the height-to-width ratio of the shell (as a one-parameter shell model) has been dismissed because of its unreliability, and more complex aspects of shell geometry have generally been overlooked. Here we use a more reliable, three-parameter geometric model of the shell outline in anterior view as a means to assess turtle paleoecology. The accuracy of predictions of extant turtle ecology based on our three-parameter shell model is comparable to that derived from forelimb proportions when distinguishing between three ecological classes (terrestrial, semiaquatic, and aquatic). Higher accuracy is obtained when distinguishing between two classes (terrestrial and non-terrestrial), because the contours of aquatic and semiaquatic turtles are often very similar. Our model classifies Proterochersis robusta, a stem turtle from the Late Triassic of Germany, as non-terrestrial, and likely semiaquatic. Our method, combined with inferences based on limb proportions, indicates a diverse range of ecotypes represented by Late Triassic stem turtles. This implies that the ecological diversification of stem-group turtles may have been rapid, or that a substantial period of currently cryptic diversification preceded the first fossil appearance of the turtle stem lineage during the Late Triassic.
The objective of this study was to report procedural characteristics and adverse events on the data collected in the IMproving Paediatric and Adult Congenital Treatment registry.
The IMproving Paediatric and Adult Congenital Treatment– registry is a catheterisation registry focussed on paediatric and adult patients with congenital heart disease who are undergoing diagnostic catheterisations and catheter-based interventions. This study reports procedural characteristics and adverse events of patients who have undergone selected catheterisation procedures from January, 2011 to June, 2013.
Demographic, clinical, procedural, and institutional data elements were collected at participating centres and entered via either a web-based platform or software provided by the American College of Cardiology-certified vendors, and were collected in a secure, centralised database. For the purpose of this study, procedures that were not classified as one of the ‘core’ IMproving Paediatric and Adult Congenital Treatment procedures originally chosen for additional data collection were identified and selected for further data analysis.
During the time frame of data collection, a total of 8021 cases were classified as other procedures and/or multiple procedures. The most commonly performed case types – isolated or in combination with other procedures – were right ventricular biopsy in 3433 (42.8%), conduit/MPA interventions in 979 (12.3%), and systemic pulmonary artery collateral occlusion in 601 (7.5%). For the whole cohort, adverse events of any severity occurred in 957 (12.0%) cases, whereas major adverse events occurred in 113 (1.4%) cases; six patients (0.1%) died in the catheterisation laboratory.
The IMproving Paediatric and Adult Congenital Treatment registry has provided important data on the frequency and spectrum of cardiac catheterisation procedures performed in the present era. For many procedures, more data and work are needed to identify more subtle differences between case categories, especially as it relates to the incidence of major adverse events, and to further develop a risk-adjustment methodology to allow equitable comparisons among institutions.
To report procedural characteristics and adverse events on data collected in the registry.
The IMPACT – IMproving Paediatric and Adult Congenital Treatment – Registry is a catheterisation registry of paediatric and adult patients with CHD undergoing diagnostic and interventional cardiac catheterisation. We are reporting the procedural characteristics and adverse events of patients undergoing diagnostic and interventional catheterisation procedures from January, 2011 to March, 2013.
Demographic, clinical, procedural, and institutional data elements were collected at the participating centres and entered via either a web-based platform or software provided by American College of Cardiology-certified vendors, and were collected in a secure, centralised database. Centre participation was voluntary.
During the time frame of data collection, 19,797 procedures were entered into the IMPACT Registry. Procedures were classified as diagnostic only (35.4%); one of six specific interventions (23.8%); other or multiple interventions (40.7%); and were further broken down into four age groups. Anaesthesia was used in 84.1% of diagnostic procedures and 87.8% of interventional ones. Adverse events occurred in 10.0% of diagnostic and 11.1% of interventional procedures.
The IMPACT Registry is gathering data to set national benchmarks for diagnostic and certain specific interventional procedures. We are seeing little differences in procedural characteristics or adverse events in diagnostic procedures compared with interventional procedures overall, but there is significant variation in adverse events amongst age categories. Risk stratification and patient acuity scores will be required for further analysis of these differences.
To determine the incidence of high jugular bulb in a group of patients with definite Ménière's disease, and to investigate whether the position or size of the jugular bulb is significantly different in the affected ear than in the unaffected ear.
Retrospective review of patient charts, audiograms, and computed tomography scans to determine the position and size of the jugular bulb in the affected and contralateral ears, as well as other abnormalities.
High jugular bulb was found in 57.1 per cent of affected ears. Encroachment of the cochlear and vestibular aqueducts was apparent in 39.3 per cent and 35.7 per cent, respectively, of affected ears. Diverticulum and dehiscence were observed in 28.6 per cent of affected ears. High jugular bulb was significantly associated with encroachment of the cochlear aqueduct (p = 0.003).
The mediolateral and anteroposterior position of the jugular bulb determines encroachment of the surrounding structures. An abnormal position is postulated to contribute to the development of Ménière's disease.