449 research outputs found
Perfluorocarbon (Oxycyte) as Innovative Therapy post Spinal Cord Injury
Spinal cord injury (SCI) is a traumatic, life-altering event, which presently, cannot be reversed. A key component of the secondary injury cascade of SCI is an inadequate blood supply (ischemia) present at the injury site, leading to a decrease in oxygen delivery (hypoxia), and possibly neuronal cell death (apoptosis). However, a third generation perfluorocarbon (OxycyteTM), at the appropriate dosage, can improve oxygenation of the injured tissue and overall motor behavior. To test this hypothesis, adult Long-Evans rats were divided into six experimental groups: a control group, a laminectomy group with no treatment, a 2 mL/kg and 5 mL/kg saline group, and a 2 mL/kg and 5 mL/kg Oxycyte group, with the focus on the 5mL/kg Oxycyte group. After performing a laminectomy on T9-T10 of the spinal cord, a 10g weight-dropping device was used at 25mm height, to mimic SCI, and the respective treatment was given. Post operation, rats were monitored and subjected to scoring according to the BBB scale and inclined plane test, to determine improvement on a functional level, day 1, 4, 7, 14, 21, 28, 35, and 42 after surgery. After functional tests were conducted, rats were euthanized for various lab tests, including histopathology and immunohistochemical analyses, to determine the key apoptotic related proteins, including caspase-3, ERK1/2, and TNFα. The results indicated a statistically significant improvement in recovery, on a functional and molecular level, in rats receiving 5 mL/kg dosage Oxycyte. However, more research of the optimal safe, efficacious dose needs to be conducted to present this research in a clinical setting.https://scholarscompass.vcu.edu/uresposters/1208/thumbnail.jp
Reaction Norms for Age and Size at Maturation: Study of the Long-Term Trend (1970-1998) for Georges Bank and Gulf of Maine Cod Stocks
Average age and size at maturation have decreased in many commercially exploited fish stocks during the last decades. This phenomenon could be either a direct phenotypic response to some environmental variation, or the evolutionary consequence of some selective pressure. Traditionally used maturation indices, i.e., the age and size at which 50% of individuals are mature, are not appropriate to assess the causes of changes in maturation because they are influenced, in addition to maturation per se, by growth and survival. To make up for this shortcoming, we use a reaction norm based approach to disentangle evolutionary changes and phenotypic plasticity. A method is presented to estimate the reaction norm for age and size at maturation from data commonly gathered for the maturation of fisheries. This method is applied to data on Georges Bank Gulf of Maine stocks of Atlantic cod ("Gadus morhua"). The results show that maturation reaction norms in these stocks have shifted significantly downwards, resulting in a tendency to mature earlier at smaller size. These findings support the hypothesis that an evolutionary trend, probably caused by high fishing mortalities, is partially responsible for the observed decrease in age and size at maturation in these cod stocks. Two independent reasons justify this interpretation. First, there is no corresponding trend in growth that would suggest that improved feeding conditions could have facilitated maturation. Second, the results are based on maturation reaction norms, from which the known confounding effects of the growth and mortality variations are removed. Consequences of fisheries-induced evolution for the sustainability of the fisheries are discussed
Estimating Reaction Norms for Age and Size at Maturation When Age at First Reproduction is Unknown
We describe a novel method to estimate the probabilities of maturing at age as a function of size; these probabilities can often be interpreted as probabilistic reaction norms for age and size at maturation. Such estimations are useful for describing maturation process independently from the processes of growth and mortality, and they can also help to disentangle phenotypic plasticity from evolutionary changes in maturation. The estimation method can be used when mature and immature individuals are representatively sampled over two consecutive seasons, even when maturing individuals are not distinguished. Confidence intervals are derived for the reaction norm parameters using a bootstrap approach. Using simulated data, the method is shown to be asymptotically unbiased and robust to moderate violations of the main simplifying assumptions. However, it is relatively sensitive to small sample sizes: the method is not robust when fewer than about 100 individuals (mature and immature) are sampled from a cohort at a certain age. The method is illustrated by an application to Georges Bank cod stock (Gadus morhua) but can be used for any type of organism
Changes in researcher capacity in assessing food safety risks and value chains: Insights from PigRisk team
Distribution of machine information using Blackboard designed component for remote monitoring of reconfigurable manufacturing systems
A blackboard-based design for a system component called the "Broadcaster" is described in this paper. It supports remote monitoring of reconfigurable manufacturing systems using a novel system architecture coupled with the Component-Based system paradigm. The design of this component has been evaluated using a case study on a web services-enabled test rig funded by the Ford Motor Company, U. K. The test rig has been implemented using a fully distributed control device called FTB, designed by the Schneider Electric Company. Evaluation of this component has been carried out using three scenario test cases which demonstrate the potentials offered when deploying this solution to a real production environment. The system component not only operates in a heterogeneous reconfigurable manufacturing environment, offering a vendor-independent solution to monitoring machines, but it also supports remote monitoring of the machines throughout their development and management lifecycles
Stage-classified matrix models and age estimates
When the size of individuals is a better indicator of their chances to survive, grow, and reproduce than their age, the suitable matrix population model is stage-classified. Cochran and Ellner developed a method to assess age-based parameters from such models. We present here, for these age estimates, simplified formulas that are valid whenever there is neither retrogression nor fission: individuals may only die, survive in the same stage, or survive and recruit to the next stage. Our formulas enable one to understand better why, and under which hypotheses, it is possible to compute age estimates from a stage-classified model, and point out some limitations of the method. These limitations in fact come from the basic hypothesis of stage-classified matrix models: stage is considered to be the only variable that influences survival and recruitment rates. As a consequence, age estimates using stage-classified models should be valid if the stages describe precisely enough the life cycles of the studied species, and particularly if senescence is taken into account
“Broadcaster”: An architectural description of a prototype supporting real-time remote data propagation in distributed manufacturing
Globalisation of manufacturing activities tend to geographically distribute manufacturing entities, resulting into each entity adopting its own mechanism, for aggregating and analysing real-time shop floor machines' information. The enterprise systems normally employ sophisticated and computationally expensive techniques to access this data, even if they operate remotely having limited network connectivity and system legacies. There is a need to propagate machine information in soft real-time basis to these entities regardless of their geographic locations and / or mechanisms. Authors are presenting an architectural description of a prototype system called the ldquoBroadcasterrdquo which efficiently distributes manufacturing machine information to a number of remotely located global engineering partners. This prototype addresses the emergent system issues like maintainability, reliability, integrity, robustness, flexibility and performance using a heterogeneous composition of ldquoBlackboardrdquo repository model with an event-driven invocation technique, implemented using interface-based strategy. The design and implementation assumes the control environment description to be engineered using the component-based system paradigm. Presently, the prototype is evaluated on a demonstration test rig provided by the Ford Motor Company, which is implemented using a fully Web services distributed control device called FTB, designed by the Schneider Electric Company. Based on the evaluation from the implementation stage, authors have justified and concluded the paper highlighting the key benefits of this approach, and described any future research that is to be carried out
A WORLDWIDE 3D GCP DATABASE INHERITED FROM 20 YEARS OF MASSIVE MULTI-SATELLITE OBSERVATIONS
Abstract. High location accuracy is a major requirement for satellite image users. Target performance is usually achieved thanks to either specific on-board satellite equipment or an auxiliary registration reference dataset. Both methods may be expensive and with certain limitations in terms of performance. The Institut national de l'information géographique et forestière (IGN) and Airbus Defence and Space (ADS) have worked together for almost 20 years, to build reference data for improving image location using multi-satellite observations. The first geometric foundation created has mainly used SPOT 5 High Resolution Stereoscopic (HRS) imagery, ancillary Ground Control Points (GCP) and Very High Resolution (VHR) imagery, providing a homogenous location accuracy of 10m CE90 almost all over the world in 2010.Space Reference Points (SRP) is a new worldwide 3D GCP database, built from a plethoric SPOT 6/7 multi-view archive, largely automatically processed, with cloud-based technologies. SRP aims at providing a systematic and reliable solution for image location (Unmanned Aerial Vehicle, VHR satellite imagery, High Altitudes Pseudo-Satellite…) and similar topics thanks to a high-density point distribution with a 3m CE90 accuracy.This paper describes the principle of SRP generation and presents the first validation results. A SPOT 6/7 smart image selection is performed to keep only relevant images for SRP purpose. The location of these SPOT 6/7 images is refined thanks to a spatiotriangulation on the worldwide geometric foundation, itself improved where needed. Points making up the future SRP database are afterward extracted thanks to classical feature detection algorithms and with respect to the expected density. Different filtering methods are applied to keep the best candidates. The last step of the processing chain is the formatting of the data to the delivery format, including metadata. An example of validation of SRP concept and specification on two tests sites (Spain and China) is then given. As a conclusion, the on-going production is shortly presented
Surgical resection of a giant peripheral ossifying fibroma in mouth floor managed with fiberscopic intubation
Tracheal intubation for general anesthesia can sometimes be difficult in patients with a large mass in the mouth floor. Preoperative evaluation of the patient's airway is most important when treating large oral disease
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