An inertial velocity reference for the NASA airborne Doppler lidar

The following four tasks were studied: (1) modification of the calibration routines to calibrate the Inertial Measurement Unit gyroscope drifts with fixed platform heading; (2) modification of the calibration routines to calibrate the Inertial Measurement Unit accelerometers; (3) checking overall software again for errors; and (4) providing documentation on the above work describing changes to the present software, results of these changes and future operating procedures

Longitudinal patterns of physical activity in children aged 8 to 12 years: the LOOK study

BACKGROUND Data on longitudinal monitoring of daily physical activity (PA) patterns in youth over successive years is scarce but may provide valuable information for intervention strategies aiming to promote PA. METHODS Participants were 853 children (starting age ~8 years) recruited from 29 Australian elementary schools. Pedometers were worn for a 7-day period each year over 5 consecutive years to assess PA volume (steps per day) and accelerometers were worn concurrently in the final 2 years to assess PA volume (accelerometer counts (AC) per day), moderate and vigorous PA (MVPA), light PA (LPA) and sedentary time (SED). A general linear mixed model was used to examine daily and yearly patterns. RESULTS A consistent daily pattern of pedometer step counts, AC, MVPA and LPA emerged during each year, characterised by increases on school days from Monday to Friday followed by a decrease on the weekend. Friday was the most active and Sunday the least active day. The percentage of girls and boys meeting international recommendations of 11,000 and 13,000 steps/day respectively on a Monday, Friday and Sunday were 36%, 50%, 21% for boys and 35%, 45%, 18% for girls. The equivalent percentages meeting the recommended MVPA of >60 min/day on these days were 29%, 39%, 16% for boys and 15%, 21%, 10% for girls. Over the 5 years, boys were more active than girls (mean steps/day of 10,506 vs 8,750; p<0.001) and spent more time in MVPA (mean of 42.8 vs 31.1 min/day; p<0.001). Although there was little evidence of any upward or downward trend in steps/day from age 8 to 12 years, there was a trend toward lower MVPA, LPA and a corresponding increase in SED from age 11 to 12 years. CONCLUSION A weekly pattern of PA occurred in children as young as age 8 on a day by day basis; these patterns persisting through to age 12. In addition to supporting previous evidence of insufficient PA in children, our data, in identifying the level and incidence of insufficiency on each day of the week, may assist in the development of more specific strategies to increase PA in community based children

Investigating the requirements of 3D dose reconstruction via optical calorimetry.

Optical calorimetry (OC) is a novel form of radiation dosimetry that used two interfering beams of light to measure the radiation induced phase change in a volume of water, and relates the phase change to absorbed dose to water. It presents a promising dosimetric method for the measurement of FLASH therapy beams, where its measurement of dose to water, lack of components perturbing the radiation beam, and dose rate independence avoids many of the technical challenges facing traditional dosimetric methods in these ultra-high dose rate beams. The current OC dosimeter outputs a 2D image of dose, integrated across the volume of water. This study aims to investigate the requirements to accurately reconstruct a 3D dose distribution through performing a tomographic reconstruction upon the 2D OC dosimeter output. Due to a desire to keep the mechanical complexity of a 3D OC dosimeter design minimised, this work looks at performing a single-projection reconstruction upon radially symmetric radiation beams using the inverse Abel transform, and performing a two-projection reconstruction on simple square and circular radiation beams using a filtered back projection or fast Fourier transform algorithm. A multi-projection reconstruction where the restriction on the number of projections used is removed was also performed, to indicate the level of mechanical complexity such an approach would entail if required. Reconstruction results showed the single-projection inverse Abel transform method could reconstruct a manually integrated proton beam to an accuracy of better than 1%, but this error increased to 8% when using the projection data generated using the FRED virtual OC dosimeter model. This error could be reduced to below 4% when the level of noise in the FRED dosimeter model was reduced to 1/8th of the full amount, indicating that an accurate 3D reconstruction using a single projection is possible, but a substantial decrease in the noise within the detector system is required. The two-projection method performed accurately in some situations, did not reliably produce accurate reconstructions of simple photon beams with clinical features modelled. The multi- projection reconstruction investigation determined that at least 25 projections would be required to achieve a reconstruction with an error below 2% for all beams investigated, representing a significant increase in mechanical complexity of the OC dosimeter design. The findings of this work recommend that in order to accurately reconstruct a 3D dose distribution using the OC dosimeter, the single-projection inverse Abel transform method could be used provided the noise in the dosimeter system is reduced, or the multi-projection FBP reconstruction method could be used provided that the additional mechanical complexity of such a design is accounted for

Human Babesia microti Incidence and Ixodes scapularis Distribution, Rhode Island, 1998–2004

Distribution of nymphal Ixodes scapularis in Rhode Island was used as a logistical regressor for predicting presence of human babesiosis. Although the incidence of babesiosis is increasing in southern Rhode Island, large areas of the state are free of babesiosis risk

Incrimination of shrews as a reservoir for Powassan virus

Powassan virus lineage 2 (deer tick virus) is an emergent threat to American public health, causing severe neurologic disease. Its life cycle in nature remains poorly understood. We use a host-specific retrotransposon-targeted real time PCR assay to test the hypothesis that white-footed mice, considered the main eastern U.S. reservoir of the coinfecting agent of Lyme disease, is the reservoir for deer tick virus. Of 20 virus-infected host-seeking nymphal black-legged ticks 65% fed on shrews and none on mice. The proportion of ticks feeding on shrews at a site is positively associated with prevalence of viral infection, but not the Lyme disease agent. Viral RNA is detected in the brain of one shrew. We conclude that shrews are a likely reservoir host for deer tick virus and that host bloodmeal analysis can provide direct evidence to incriminate reservoir hosts, thereby promoting our understanding of the ecology of tick-borne infections

Outcomes of a four-year specialist-taught physical education program on physical activity: a cluster randomized controlled trial, the LOOK study

BackgroundThe objective of this study was to investigate the effect of a 4-year specialist-taught Physical Education (PE) program on physical activity (PA) among primary school children.MethodsA 4-year cluster randomised controlled trial was conducted in children (initially aged 8 years) from 29 primary schools (13 Intervention, 16 Control). Intervention students (N&thinsp;=&thinsp;457) received 2&thinsp;&times;&thinsp;45 min PE lessons per week from specialist-trained PE teachers (68 lessons per year, 272 lessons over 4 years). Control group students (N&thinsp;=&thinsp;396) received usual practice PE from generalist classroom teachers. PA during PE lessons was examined using the System for Observing Fitness Instruction Time (SOFIT). Pedometers (steps/day) were worn for 7 days each year, and accelerometers were worn concurrently in the final two years to assess moderate to vigorous (MVPA) and sedentary activity. Linear and generalized mixed models were used to determine differences in Intervention and Control student PA and the proportion of students meeting PA guidelines.ResultsThe intervention increased SOFIT-observed student MVPA during PE lessons by 6.5 mins (16.7 v 10.2, p&thinsp;&lt;&thinsp;0.001). Within intervention schools, participants increased their whole-day step counts (boys&thinsp;=&thinsp;449 [CI,140 to 756]; girls&thinsp;=&thinsp;424 [CI,222 to 626]) and minutes of MVPA (boys&thinsp;=&thinsp;8.0 [CI,6.8 to 9.2]; girls&thinsp;=&thinsp;3.5 [CI,1.7 to 5.4]) on PE days. However, compared to the Control group the Intervention did not: increase habitual steps/day or MVPA when averaged over 7 days; elicit greater improvements in these measures over time; or increase the odds of meeting step/day or MVPA recommendations. At age 11 years Intervention group boys were 20 mins less sedentary per day (380 [CI,369 to 391] vs 360 [CI,350 to 369]) and this effect was sustained at age 12 years.ConclusionsWell-designed specialist-taught PE can improve student PA during PE lessons. However for PE to be a significant contributor to improving habitual PA in pre-adolescent children, daily classes are likely to be required, and even this would need to be supplemented with a wider multicomponent strategy. Our finding of a reduction in sedentary time among Intervention boys warrants further investigation into the potential role PE could play in influencing sedentary behaviour.<br /

Reversals in Temperature-Precipitation Correlations in the Northern Hemisphere Extratropics During the Holocene

Future precipitation levels remain uncertain because climate models have struggled to reproduce observed variations in temperature-precipitation correlations. Our analyses of Holocene proxy-based temperature-precipitation correlations and hydrological sensitivities from 2,237 Northern Hemisphere extratropical pollen records reveal a significant latitudinal dependence and temporal variations among the early, middle, and late Holocene. These proxy-based variations are largely consistent with patterns obtained from transient climate simulations (TraCE21k). While high latitudes and subtropical monsoon areas show mainly stable positive correlations throughout the Holocene, the mid-latitude pattern is temporally and spatially more variable. In particular, we identified a reversal from positive to negative temperature-precipitation correlations in the eastern North American and European mid-latitudes from the early to mid-Holocene that mainly related to slowed down westerlies and a switch to moisture-limited convection under a warm climate. Our palaeoevidence of past temperature-precipitation correlation shifts identifies those regions where simulating past and future precipitation levels might be particularly challenging.publishedVersio

Receptor-Binding and Oncogenic Properties of Polyoma Viruses Isolated from Feral Mice

Laboratory strains of the mouse polyoma virus differ markedly in their abilities to replicate and induce tumors in newborn mice. Major determinants of pathogenicity lie in the sialic binding pocket of the major capsid protein Vp1 and dictate receptor-binding properties of the virus. Substitutions at two sites in Vp1 define three prototype strains, which vary greatly in pathogenicity. These strains replicate in a limited fashion and induce few or no tumors, cause a disseminated infection leading to the development of multiple solid tumors, or replicate and spread acutely causing early death. This investigation was undertaken to determine the Vp1 type(s) of new virus isolates from naturally infected mice. Compared with laboratory strains, truly wild-type viruses are constrained with respect to their selectivity and avidity of binding to cell receptors. Fifteen of 15 new isolates carried the Vp1 type identical to that of highly tumorigenic laboratory strains. Upon injection into newborn laboratory mice, the new isolates induced a broad spectrum of tumors, including ones of epithelial as well as mesenchymal origin. Though invariant in their Vp1 coding sequences, these isolates showed considerable variation in their regulatory sequences. The common Vp1 type has two essential features: 1) failure to recognize “pseudoreceptors” with branched chain sialic acids binding to which would attenuate virus spread, and 2) maintenance of a hydrophobic contact with true receptors bearing a single sialic acid, which retards virus spread and avoids acute and potentially lethal infection of the host. Conservation of these receptor-binding properties under natural selection preserves the oncogenic potential of the virus. These findings emphasize the importance of immune protection of neonates under conditions of natural transmission