Dendritic cells induce antigen-specific regulatory T cells that prevent graft versus host disease and persist in mice

Foxp3 + regulatory T cells (T reg cells) effectively suppress immunity, but it is not determined if antigen-induced T reg cells (iT reg cells) are able to persist under conditions of inflammation and to stably express the transcription factor Foxp3. We used spleen cells to stimulate the mixed leukocyte reaction (MLR) in the presence of transforming growth factor β (TGF-β) and retinoic acid. We found that the CD11c high dendritic cell fraction was the most potent at inducing high numbers of alloreactive Foxp3 + cells. The induced CD4 +CD25 +Foxp3 + cells appeared after extensive proliferation. When purified from the MLR, iT reg cells suppressed both primary and secondary MLR in vitro in an antigen-specific manner. After transfer into allogeneic mice, iT reg cells persisted for 6 mo and prevented graft versus host disease (GVHD) caused by co-transferred CD45RB hi T cells. Similar findings were made when iT reg cells were transferred after onset of GVHD. The CNS2 intronic sequence of the Foxp3 gene in the persisting iT reg cells was as demethylated as the corresponding sequence of naturally occurring T reg cells. These results indicate that induced Foxp3 + T reg cells, after proliferating and differentiating into antigen-specific suppressive T cells, can persist for long periods while suppressing a powerful inflammatory disease

Highly Reusable Space Transportation System Concept Evaluation (The Argus Launch Vehicle)

This paper summarizes the results of a conceptual design study that was performed in support of NASA's recent Highly Reusable Space Transportation study. The Argus concept uses a Maglifter magnetic-levitation sled launch assist system to accelerate it to a takeoff ground speed of 800 fps on its way to delivering a payload of 20,000 lb. to low earth orbit. Main propulsion is provided by two supercharged ejector rocket engines. The vehicle is autonomous and is fully reusable. A conceptual design exercise determined the vehicle gross weight to be approximately 597,250 lb. and the dry weight to be 75,500 lb. Aggressive weight and operations cost assumptions were used throughout the design process consistent with a second-generation reusable system that might be deployed in 10-15 years. Drawings, geometry, and weight of the concept are included. Preliminary development, production, and operations costs along with a business scenario assuming a price-elastic payload market are also included. A fleet of three Argus launch vehicles flying a total of 149 flights per year is shown to have a financial internal rate of return of 28%. At $169/lb., the recurring cost of Argus is shown to meet the study goal of$100/lb.-$200/lb., but optimum market price results in only a factor of two to five reduction compared to today's launch systems

Explorando el océano a través de paisajes sonoros

Listening to underwater soundscapes helps us understand how ocean physics and the biology of marine communities are responding to a dynamically changing ocean.Escuchar paisajes sonoros submarinos nos ayuda a entender cómo la física oceánica y la biología de las comunidades marinas están respondiendo a un océano que cambia dinámicamente

Fitting the man to the machine: The ADAPT project

The size and shape of humans have been changing dramatically over the last 100 years. People have grown taller and fatter, with relatively longer legs and higher waist–hip ratios. Aircraft, on the other hand, are often designed to last for several decades. Consequently, there is an increasing mismatch between the size and shape of crewstations and the size and shape of aircrew. This mismatch has been exacerbated by the introduction of female aircrew. This is particularly true in Australia, where the most recent anthropometric survey dates from the 1970s, and crewstations are designed based on overseas specifications. In the past, anthropometric surveys have been conducted with the traditional instruments of tape measures and calipers. The Australian Defence Anthropometric Personnel Testing (ADAPT) project is taking a different approach, using a combination of 3D whole-body scanners, laser scans of crewstations, human modelling and animation software, and mathematical optimisation, to refine anthropometric recruitment standards for the RAAF. The project will additionally improve clothing and equipment fit, human functionality in aircraft, reduce the risk of injury and provide the opportunity to open recruitment to a wider selection of applicants. The work done in the ADAPT project has applications across the ADF, and will spill over into many civilian fields.C

The effects of an area-based intervention on the uptake of maternal and child health assessments in Australia: A community trial

Background Recognition of the importance of the early years in determining health and educational attainment and promotion of the World Health Organization Health for All (HFA) principles has led to an international trend towards community-based initiatives to improve developmental outcomes among socio-economically disadvantaged children. In this study we examine whether, Best Start, an Australian area-based initiative to improve child health was effective in improving access to Maternal and Child Health (MCH) services. Methods The study compares access to information, parental confidence and annual 3.5 year Ages and Stages visiting rates before (2001/02) and after (2004/05) the introduction of Best Start. Access to information and parental confidence were measured in surveys of parents with 3 year old children. There were 1666 surveys in the first wave and 1838 surveys in the second wave. The analysis of visiting rates for the 3.5 year Ages and Stages visit included all eligible Victorian children. Best Start sites included 1,739 eligible children in 2001/02 and 1437 eligible children in 2004/05. The comparable figures in the rest of the state were and 45, 497 and 45, 953 respectively. Results There was a significant increase in attendance at the 3.5 year Ages and Stages visit in 2004/05 compared to 2001/02 in all areas. However the increase in attendance was significantly greater at Best Start sites than the rest of the state. Access to information and parental confidence improved over the course of the intervention in Best Start sites with MCH projects compared to other Best Start sites. Conclusion These results suggest that community-based initiatives in disadvantaged areas may improve parents' access to child health information, improve their confidence and increase MCH service use. These outcomes suggest such programmes could potentially contribute to strategies to reduce child health inequalities

International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) : Contributions to Understanding the Global Obesity Epidemic

The purpose of this review is to summarize the scientific contributions of the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) in extending our understanding about obesity in children from around the world. ISCOLE was a multi-national study of 9 to 11 year-old children from sites in 12 countries from all inhabited continents. The primary purpose was to investigate relationships between lifestyle behaviors and obesity, and the influence of higher-order characteristics such as behavioral settings, and physical, social and policy environments. ISCOLE has made several advances in scientific methodology related to the assessment of physical activity, dietary behavior, sleep and the neighborhood and school environments. Furthermore, ISCOLE has provided important evidence on (1) epidemiological transitions in obesity and related behaviors, (2) correlates of obesity and lifestyle behaviors at the individual, neighborhood and school levels, and (3) 24-h movement behaviors in relation to novel analytical techniques. A key feature of ISCOLE was the development of a platform for international training, data entry, and data quality for multi-country studies. Finally, ISCOLE represents a transparent model for future public-private research partnerships across low, middle and high-income countries.Peer reviewe

Noise level correlates with manatee use of foraging habitats

Author Posting. © Acoustical Society of America, 2007. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 121 (2007): 3011-3020, doi:10.1121/1.2713555.The introduction of anthropogenic sound to coastal waters is a negative side effect of population growth. As noise from boats, marine construction, and coastal dredging increases, environmental and behavioral monitoring is needed to directly assess the effect these phenomena have on marine animals. Acoustic recordings, providing information on ambient noise levels and transient noise sources, were made in two manatee habitats: grassbeds and dredged habitats. Recordings were made over two 6-month periods from April to September in 2003 and 2004. Noise levels were calculated in one-third octave bands at nine center frequencies ranging from 250 Hz to 64 kHz. Manatee habitat usage, as a function of noise level, was examined during four time periods: morning, noon, afternoon, and night. Analysis of sightings data in a variety of grassbeds of equal species composition and density indicate that manatees select grassbeds with lower ambient noise for frequencies below 1 kHz. Additionally, grassbed usage was negatively correlated with concentrated boat presence in the morning hours; no correlation was observed during noon and afternoon hours. This suggests that morning boat presence and its associated noise may affect the use of foraging habitat on a daily time scale.This research was supported by a P.E.O. Scholar Award and National Defense Science and Engineering Graduate Fellowship awarded to Jennifer Miksis

Physical Education Classes, Physical Activity, and Sedentary Behavior in Children

Purpose This study aimed to examine the associations between participation frequency in physical education (PE) classes and objective measures of physical activity (PA) and sedentary behavior (SB) in children from 12 countries at different levels of development. Methods This multinational, cross-sectional study included 5874 children 9-11 yr old from sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. PA and SB were monitored for seven consecutive days using a waist-worn accelerometer. PA and SB data were presented for weekdays (times in and out of school) and weekend days. Participation frequency in PE classes was determined by questionnaire. Multilevel modeling analyses stratified by sex were used. Results Overall, 24.8% of children self-reported participation in PE classes ≥3 times per week (25.3% in high-income countries [HIC] and 24.3% in low- and middle-income countries [LMIC]). After adjusting for age, sex, parental education, and body mass index z-score, results showed that children from low- and middle-income countries who took PE classes one to two times per week were more likely to present better indicators of PA and shorter time in SB in and out of school. In HIC, boys that participated in PE classes were more likely to meet the moderate-to-vigorous PA recommendations and to present better indicators of PA (in school) and shorter time in SB in and out of school. For girls in HIC, attending PE classes increased the likelihood of spending more time in moderate-to-vigorous PA, especially if they attended ≥3 times per week. Conclusion Attending PE classes is associated with a higher level of PA and a lower level of SB in and out of school during weekdays in children from countries at various levels of development.</p

Adiposity and the isotemporal substitution of physical activity, sedentary time and sleep among school-aged children : a compositional data analysis approach

Background: Daily activity data are by nature compositional data. Accordingly, they occupy a specific geometry with unique properties that is different to standard Euclidean geometry. This study aimed to estimate the difference in adiposity associated with isotemporal reallocation between daily activity behaviours, and to compare the findings from compositional isotemporal subsitution to those obtained from traditional isotemporal substitution. Methods: We estimated the differences in adiposity (body fat%) associated with reallocating fixed durations of time (isotemporal substitution) between accelerometer-measured daily activity behaviours (sleep, sedentary time and light and moderate-to-vigorous physical activity (MVPA)) among 1728 children aged 9-11 years from Australia, Canada, Finland and the UK (International Study of Childhood Obesity, Lifestyle and the Environment, 2011-2013).We generated estimates from compositional isotemporal substitution models and traditional non-compositional isotemporal substitution models. Results: Both compositional and traditional models estimated a positive (unfavourable) difference in body fat% when time was reallocated from MVPA to any other behaviour. Unlike traditional models, compositional models found the differences in estimated adiposity (1) were not necessarily symmetrical when an activity was being displaced, or displacing another (2) were not linearly related to the durations of time reallocated, and (3) varied depending on the starting composition. Conclusion: The compositional isotemporal model caters for the constrained and therefore relative nature of activity behaviour data and enables all daily behaviours to be included in a single statistical model. The traditional model treats data as real variables, thus the constrained nature of time is not accounted for, nor reflected in the findings. Findings from compositional isotemporal substitution support the importance of MVPA to children's health, and suggest that while interventions to increase MVPA may be of benefit, attention should be directed towards strategies to avoid decline in MVPA levels, particularly among already inactive children. Future applications of the compositional model can extend from pair-wise reallocations to other configurations of time-reallocation, for example, increasing MVPA at the expense of multiple other behaviours.Peer reviewe

Temporal and bi-directional associations between sleep duration and physical activity/sedentary time in children:An international comparison

The purpose of this multinational and cross-sectional study was to investigate whether nighttime sleep duration was associated with physical activity (PA) and sedentary time (SED) the following day, whether daytime PA/SED were associated with sleep duration the subsequent night, and whether the associations were modified by sex and study sites. Data from 5779 children aged 9-11years were analyzed. A waist-worn Actigraph GT3X+ accelerometer was used to assess children's 24-h movement behaviours for 7days, i.e. sleep duration, total SED, light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA). Multilevel linear regression models were used to account for the repeated measures nested within participants (there were up to 7 sleep→PA/SED and PA/SED→sleep pairings per participant) and schools, and adjusted for covariates. To facilitate interpretation, all sleep and PA/SED variables were standardized. Results showed that the relationship between sleep and PA/SED is bi-directional in this international sample of children. Specifically, for each one standard deviation (SD) unit increase in sleep duration, SED the following day decreased by 0.04 SD units, while LPA and MVPA increased by 0.04 and 0.02 SD units, respectively. Sleep duration decreased by 0.02 SD units and increased by 0.04 SD units for each one SD unit increase in SED and MVPA, respectively. Sleep duration was not affected by changes in LPA. These associations differed across sex and study sites in both directions. However, since the observed effect sizes are subtle, public health initiatives should consider the clinical and practical relevance of these findings.</p