4,691 research outputs found
Monitoring cardiovascular function in the primate under prolonged weightlessness
Monitoring cardiovascular function in primates under prolonged weightlessnes
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e-Governance: Supporting pragmatic direct deliberative action through online communities of interest
Authors often report on the limited success of e-Government initiatives in developing nations. Top down, national strategies are developed to target improved government services, but maintain hierarchical, citizen-state conceptions of governance through representative democracy. An alternative conception, direct deliberative democracy, frames the potential role of the internet in governance differently. Web based platforms might support locally animated deliberations, which target pragmatic outcomes, while the resulting social networks afford collective learning through connections across traditional boundaries. This paper presents an investigation of direct deliberative governance as it occurs in online 'communities of interest', and is based on research with such a community in southern Africa. We investigate contributions to the online governance process and develop an action typology distinguishing between degrees of 'agency freedom'. Network analytic techniques are then used to understand how acts of varying degree are expressed in terms of the structure of a social network. The aim, more broadly, is to understand how the environment shapes acts of direct deliberative governance, and, in turn, how the acts shape the evolution and effectiveness of the community. The preliminary results suggest design considerations for online governance communities, and highlight their role to not only provide deliberative space, but to mediate social network connections
Estimating Animal Abundance with N-Mixture Models Using the R-INLA Package for R
Successful management of wildlife populations requires accurate estimates of abundance. Abundance estimates can be confounded by imperfect detection during wildlife surveys. N-mixture models enable quantification of detection probability and, under appropriate conditions, produce abundance estimates that are less biased. Here, we demonstrate how to use the R-INLA package for R to analyze N-mixture models, and compare performance of R-INLA to two other common approaches: JAGS (via the runjags package for R), which uses Markov chain Monte Carlo and allows Bayesian inference, and the unmarked package for R, which uses maximum likelihood and allows frequentist inference. We show that R-INLA is an attractive option for analyzing N-mixture models when (i) fast computing times are necessary (R-INLA is 10 times faster than unmarked and 500 times faster than JAGS), (ii) familiar model syntax and data format (relative to other R packages) is desired, (iii) survey-level covariates of detection are not essential, and (iv) Bayesian inference is preferred
STABILISING THE HIP AND PELVIS DURING RUNNING: IS THERE AN EXPLOSIVE SOLUTION FOR UNINJURED ATHLETES?
We compared the effectiveness of a conventional (slow-controlled) to a novel (explosive) eight week training program designed to improve lateral stability at the pelvis and hip during a running task. Parameters included: frontal-plane kinematics (500 Hz); electromyography recordings (1000 Hz) of gluteus medius (GM) and tensor fasciae latae (both sides); and oxygen kinetics. The groups were matched for hip and pelvis kinematics. After the training, reduction in peak angles at the hip and pelvis improved compared to baseline data regardless of group membership. Differences between groups were also found. Only the explosively trained group displayed changed GM onset times, where GM activation occurred earlier prior to ground contact when running. These differences in GM onsets support the notion of specific training adaptations, and the mechanism for hip and pelvis stability may not be the same for both groups. In addition, only the explosive group improved running performance (economy) further justifying this method of prescription
A method of predicting variable speed rail corrugation growth using standard statistical moments
Wear-type rail corrugation is a significant problem in the railway transport industry. Some recent work has suggested that speed control can be used as an effective tool to minimize the rate of corrugation growth. This has brought about the need to model corrugation growth under variable passing speed. Variable speed rail corrugation growth modelling normally consists of either numerical simulation of a sequence of varied speed wheel passes or direct integration of a probabilistic passing speed distribution function; both of which are computationally expensive. This paper investigates the use of the statistical moments of the speed probability density function to greatly improve the computational speed of variable speed corrugation growth models and compares results of changing standard deviation and skewness to numerical integration models. It also identifies the effects of individual statistical moments on corrugation growth to provide better insight into control methods. The new modelling method correlated well with the numerical integration models for small standard deviations in speed (less than 10%) and highlighted a need to consider kurtosis in predicting the performance of speed control based corrugation mitigation schemes. For larger standard deviations in speed, higher than 4th order effects need to be considered
Modularization for the Cell Ontology
One of the premises of the OBO Foundry is that development of an orthogonal set of ontologies will increase domain expert contributions and logical interoperability, and decrease maintenance workload. For these reasons, the Cell Ontology (CL) is being re-engineered. This process requires the extraction of sub-modules from existing OBO ontologies, which presents a number of practical engineering challenges. These extracted modules may be intended to cover a narrow or a broad set of species. In addition, applications and resources that make use of the Cell Ontology have particular modularization requirements, such as the ability to extract custom subsets or unions of the Cell Ontology with other OBO ontologies. These extracted modules may be intended to cover a narrow or a broad set of species, which presents unique complications.

We discuss some of these requirements, and present our progress towards a customizable simple-to-use modularization tool that leverages existing OWL-based tools and opens up their use for the CL and other ontologies
Probabilistic Prediction of Wheel Squeal under Field Humidity Variation
This research examines the effect of changes in coefficient of friction due to humidity on the likelihood of wheel squeal events occurring in practice. Theoretical mechanics based modeling is developed and compared to a database of field measurements of wheel squeal occurrences at a field site in Australia. In particular, a relatively simplified model of wheel squeal is developed based on existing literature but notably incorporates probabilistic mechanics to account for field parameter variations and hence allows direct comparisons with field data. The model is then tuned to field site conditions at which over 2 million wheel passes have been monitored for a period of 3 years. The comparison indicates that field measured trends for the effect of relative humidity on coefficient of friction and hence the occurrences of wheel squeal have been able to be predicted using the very efficient model
Quantitative magnetophoresis of micro and nano particles
Micro- and nanoscale magnetic particles are becoming increasingly utilized in a variety of settings. Magnetophoresis is commonly used in diagnostic devices, research applications, and medicinal science. The applications of magnetophoresis in drug delivery, gene transfection, and hyperthermic treatment of tumours are in the initial phases of development. While a large body of work in magnetophoresis exists, here are few reports of the relevant magnetophoretic parameters of a system being quantitatively correlated with driven particle mobility. The relationships between the size, shape, and magnetic properties of the particles, the applied magnetic field, and the viscosity of the medium are relevant to particle magnetophoresis and the design of magnetophoretic systems. The investigation described here begins with the room temperature magnetic characterization of the three particles used: commercial beads, nanorods, and for the first time ferritin. Ferritin is a magnetic protein which has been used extensively in a research context for labelling biological particles, however such systems have not been quantifiably characterized to enable the development of loading/force causal relationships. Here, a model platform was used to correlate for the first time, the quantified ferritin loading, the empirically determined magnetic properties of the ferritin labelled particles, and the magnetophoretic forces. The quantified magnetophoresis of spheres and rods in a model viscous medium and shear thinning polymer networks was performed for the first time. This investigation also represents the first report of particle shear thinning of DNA. The decreasing viscosity experienced by the particles in DNA points toward potential implications for considering the benefits of particle induced shear thinning in the designing of magnetic particle drug delivery systems. In the final investigation, the results of the previous chapters are brought together in the fabrication and magnetophoresis of a novel, ferritin based, rod shaped, biocompatible, nanoparticles. For the first time, magnetophoresis of the nanoparticles is demonstrated and validated by spatially resolved Raman spectroscopic analysis of the magnetically concentrated material. This dual component magnetic particle has potential application in the fabrication of new functionally graded biomaterials and drug and gene delivery
Blood, fire and fertility : human remains and ritual practices at the temple pyramid groups of Cantona, Puebla, Mexico
La ville préhispanique de Cantona, située dans la vallée d’Oriental dans l’état de Puebla au Mexique, atteignit sa première apogée culturelle entre 150 av. J.C. et 600/650 A.D. Durant cette période, des complexes cérémoniaux comprenant des groupes de pyramides-temples et des terrains de jeu de balle furent construits. Ces installations servirent au déroulement de nombreux rites au cours desquels les victimes de sacrifices étaient décapitées, démembrées, décharnées, écorchées, bouillies, brûlées et, dans certains cas, consommées. D’autres traitements du corps humain comportent l’inhumation d’individus en position assise et repliés sur eux-mêmes. Pour mieux comprendre le traitement mortuaire rituel des corps humains à Cantona, les découvertes faites sur place sont comparées aux données datant de la même époque obtenues dans trois régions voisines : la vallée de Mexico, Puebla-Tlaxcala et le golfe du Mexique. A partir de ces renseignements, on peut en déduire que la majorité des découvertes faites à Cantona sont les restes des dépouilles et offrandes provenant de rites destinés à la communication avec les dieux et à l’obtention de la fertilité, tandis que les dépouilles des individus en position assise appartiennent à des prêtres ou à des personnages religieux.The prehispanic city of Cantona, located in the Valley of Oriental in the state of Puebla, Mexico, reached its first cultural apogee between 150 B.C. - 600/650 A.D. During this time, ceremonial complexes such as Temple Pyramid Groups and ballcourts were constructed. These served as the location for a number of rituals involving the beheading, dismemberment, defleshing, flaying, boiling, burning, and in some cases, the consumption of sacrifice victims. Other human body treatment included the burial of individuals in flexed seated positions. To better understand the ritual mortuary treatment of human bodies at Cantona, the finds are compared with data from three neighboring areas: the Valley of Mexico, Puebla-Tlaxcala, and the Gulf of Mexico. From this information, it can be deduced that most of discoveries at Cantona are the remains of rites dedicated to deity communication and fertility while those of individuals in flexed, seated positions belong to religious actors.La ciudad prehispánica de Cantona, ubicada en el valle de Oriental dentro del estado de Puebla, Mexico, tuvo su primer apogeo cultural entre 150 a.ne. y 600/650 d.n.e. Durante ese periodo, se edificaron gran número de complejos ceremoniales tal como Grupos de Templo Pirámide y canchas de juego de pelota. Estas construcciones sirvieron como sitios rituales en donde se llevaron a cabo gran número de ritos, los cuales, en parte, consistÃan en decapitar, desmembrar, descarnar, desollar, hervir, quemar, y, en algunos casos, comer a las vÃctimas humanas de los sacrificios. En otros casos, los cuerpos humanos fueron encontrados en posición flexionada y sentada. Para entender mejor el tratamiento ritual de cuerpos humanos en Cantona, estos descubrimientos fueron comparados con información obtenida de tres regiones cercanas: el Valle de México, Puebla-Tlaxcala y la Costa del Golfo. Esto permitió deducir que la mayorÃa de los hallazgos en Cantona representan los restos de ritos dedicados a la comunicación con divinidades y a la fertilidad, mientras que los individuos encontrados en posición flexionada y sentada corresponden a sacerdotes o actores rituales difuntos
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