Diagnosis and treatment of hereditary hemorrhagic telangiectasia in a pediatric patient with chronic cyanosis.

Background: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder of vascular dysplasias that is characterized by mucocutaneous telangiectasias, gastrointestinal tract bleeding, and arteriovenous malformations (AVMs) of the pulmonary, hepatic, and cerebral vascular systems. Case Summary: A seven-year-old boy presented to his primary care provider with a five-day history of watery diarrhea and was incidentally found to have oxygen saturations in the low eighties, perioral cyanosis, and clubbing on physical exam. He was referred to the pediatric emergency department (ED) for evaluation. Upon presentation to the pediatric ED, oxygen saturation ranged from 74-85%. He was in no acute distress and was afebrile with normal vital signs. The patient was small for his age with height and weight in the thirteenth and third percentiles, respectively, and had central cyanosis and clubbing of fingers and toes. Auscultation revealed diminished lung sounds in the right lower lobe. No mucocutaneous telangiectasias or cardiac murmurs were appreciated. Family history was positive for hereditary hemorrhagic telangiectasia (HHT) with gastrointestinal bleeding and anemia in his maternal great grandmother and maternal grandmother, minor bleeding and mucocutaneous telangiectasias in his mother, and cyanosis with exercise and recurrent epistaxis in his brother. Complete blood count was significant for a hemoglobin level of 18.1 g/dL. A chest x-ray (Figure 1) showed an airspace opacification within the superior segment of the right lower lobe suspicious for an arteriovenous malformation (AVM).peer-reviewe

Shared understandings of dementia? : An application of the Common Sense Self Regulation Model to a case study

Peer reviewedPostprin

13 Years of Timing of PSR B1259-63

This paper summarizes the results of 13 years of timing observations of a unique binary pulsar, PSR B1259$-$63, which has a massive B2e star companion. The data span encompasses four complete orbits and includes the periastron passages in 1990, 1994, 1997 and 2000. Changes in dispersion measure occurring around the 1994, 1997 and 2000 periastrons are measured and accounted for in the timing analysis. There is good evidence for a small glitch in the pulsar period in 1997 August, not long after the 1997 periastron, and a significant frequency second derivative indicating timing noise. We find that spin-orbit coupling with secular changes in periastron longitude and projected semi-major axis ($x$) cannot account for the observed period variations over the whole data set. While fitting the data fairly well, changes in pulsar period parameters at each periastron seem ruled out both by X-ray observations and by the large apparent changes in pulsar frequency derivative. Essentially all of the systematic period variations are accounted for by a model consisting of the 1997 August glitch and step changes in $x$ at each periastron. These changes must be due to changes in the orbit inclination, but we can find no plausible mechanism to account for them. It is possible that timing noise may mask the actual changes in orbital parameters at each periastron, but the good fit to the data of the $x$ step-change model suggests that short-term timing noise is not significant.Comment: 9 pages, 7 figures, accepted by MNRA

On Estimates of Split-Ticket Voting: EI and EMax

Cho and Gaines have recently criticized work by Burden and Kimball on split-ticket voting in the USA, suggesting that their estimates of the volume of such voting (derived using King�s EI method) across Congressional Districts and States are unreliable. Using part of the Burden-Kimball data set, we report on a parallel set of estimates generated by a different procedure (EMax), which employs three rather than two sets of bounds. The results are extremely similar to Burden and Kimball�s, providing strong circumstantial evidence for their conclusions regarding the impact of campaign spending and other influences on the volume of split-ticket voting

Exploring the Relationship Between Daily Steps, Body Mass Index and Physical Self-Esteem in Female Australian Adolescents

Current research suggests that a decline in physical activity occurs some time during the adolescent years, but at what specific age is unknown. Determination of the age at which physical activity levels decline and possible contributors to this phenomenon, are needed to increase Australian healthcare knowledge. The participants involved in the study were female adolescents (n = 297) aged 13-15 years from a high school in Southeast Queensland, Australia. The purpose of this study was to: (a) determine mean steps per day, using pedometers, for grade 8 through 10 girls, (b) determine body mass index (BMI) by measuring height (cm) and weight (kg), and (c), using the Children and Youth Physical Self-Perception Profile (CY-PSPP) questionnaire, identify determinants of physical self-worth in Australian female adolescents and their relationship to activity level and BMI. The study revealed that a significant drop-off in pedometer-determined mean daily steps occurred at grade ten, or approximately 15 years of age. A significant inverse relationship between mean daily steps and BMI was found (r = ¯.251, p<.0001). The study also revealed negative correlations between BMI and all self-perceptions (p<.05), except strength, which showed a positive correlation (p<0.05). A positive correlation was found between level of physical activity and all self-perceptions, except Global Self-Worth, which showed no significant difference

How does grain size distribution impact the mobility and deposition of analogue pyroclastic density currents?

Pyroclastic density currents (PDCs) are hot, density-driven flows of gas, rock and ash generated during explosive volcanic eruptions or from the collapse of lava domes. PDCs are able to travel for tens of km, traversing topographic barriers hundreds of metres high. They are notably more mobile than other gravity currents of comparable size. Gas fluidisation has been attributed as a major contributor to this high mobility. Experimentation on non-fluidised granular flows has assessed the influence of grainsize on mobility, finding that the finer the grains, the larger the mobility of the mass. Recent advances in analogue models of gas-fluidised granular currents have revealed the impact of aeration on current mobility, and how flow behaviour can control deposit architecture and morphology. However, these experiments have so far largely used only a single grain-size.The impact of grain size variations on the mobility of aerated granular currents remains untested. Therefore, this project investigated the impact of grain size distribution on current velocity and run-out distance in a series of analogue experiments using an aerated flume.The experiments demonstrate that the mobility of these dense granular currents is related to the proportion of fines within the current but is primarily controlled by the initial sorting of the current. The more well sorted currents have a lower velocity but a greater run-out distance than the poorly sorted currents. The proportion of fines is found to have very little control on current velocity, but does have some control on run-out distance and degree of non-uniformity in velocity. Deposition during the analogue experiments occurs by a combination of gradual and stepwise aggradation.This work contributes our understanding of PDC mobility and how mobility can be interpreted from ignimbrites, with implications for numerical modelling and hazard mapping of PDCs

Autonomous RPRV Navigation, Guidance and Control

Dryden Flight Research Center has the responsibility for flight testing of advanced remotely piloted research vehicles (RPRV) to explore highly maneuverable aircraft technology, and to test advanced structural concepts, and related aeronautical technologies which can yield important research results with significant cost benefits. The primary purpose is to provide the preliminary design of an upgraded automatic approach and landing control system and flight director display to improve landing performance and reduce pilot workload. A secondary purpose is to determine the feasibility of an onboard autonomous navigation, orbit, and landing capability for safe vehicle recovery in the event of loss of telemetry uplink communication with the vehicles. The current RPRV approach and landing method, the proposed automatic and manual approach and autoland system, and an autonomous navigation, orbit, and landing system concept which is based on existing operational technology are described