1,119 research outputs found
Intelligent reconfiguration of large mobile networks using complex organic distributed architecture
This paper presents a possible solution to the intelligent evolution of mobile systems using a Complex Organic Distributed Architecture (CODA), which supports intelligent
reconfiguration of all system components. A key feature of this architecture is the deployment of multiple warehouses. The warehouses store data in a variety of ways depending on the type of intelligence required. On Line Analytical Processing (OLAP) software is used to monitor and control data in the system. An effective system of filters and
wrappers ensures that data is secure. A system of feedback loops ensures that information travels through the system quickly and effectively
Assessment of left atrial volume before and after pulmonary thromboendarterectomy in chronic thromboembolic pulmonary hypertension.
BackgroundImpaired left ventricular diastolic filling is common in chronic thromboembolic pulmonary hypertension (CTEPH), and recent studies support left ventricular underfilling as a cause. To investigate this further, we assessed left atrial volume index (LAVI) in patients with CTEPH before and after pulmonary thromboendarterectomy (PTE).MethodsForty-eight consecutive CTEPH patients had pre- & post-PTE echocardiograms and right heart catheterizations. Parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index, LAVI, & mitral E/A ratio. Echocardiograms were performed 6 ± 3 days pre-PTE and 10 ± 4 days post-PTE. Regression analyses compared pre- and post-PTE LAVI with other parameters.ResultsPre-op LAVI (mean 19.0 ± 7 mL/m2) correlated significantly with pre-op PVR (R = -0.45, p = 0.001), mPAP (R = -0.28, p = 0.05) and cardiac index (R = 0.38, p = 0.006). Post-PTE, LAVI increased by 18% to 22.4 ± 7 mL/m2 (p = 0.003). This change correlated with change in PVR (765 to 311 dyne-s/cm5, p = 0.01), cardiac index (2.6 to 3.2 L/min/m2, p = 0.02), and E/A (.95 to 1.44, p = 0.002).ConclusionIn CTEPH, smaller LAVI is associated with lower cardiac output, higher mPAP, and higher PVR. LAVI increases by ~20% after PTE, and this change correlates with changes in PVR and mitral E/A. The rapid increase in LAVI supports the concept that left ventricular diastolic impairment and low E/A pre-PTE are due to left heart underfilling rather than inherent left ventricular diastolic dysfunction
Synergistic photothermal ablative effects of functionalizing carbon nanotubes with a POSS-PCU nanocomposite polymer
10.1186/1477-3155-10-34Journal of Nanobiotechnology10-JNOA
Vulnerability analysis of satellite-based synchronized smart grids monitoring systems
The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks
Verification and Control of Partially Observable Probabilistic Real-Time Systems
We propose automated techniques for the verification and control of
probabilistic real-time systems that are only partially observable. To formally
model such systems, we define an extension of probabilistic timed automata in
which local states are partially visible to an observer or controller. We give
a probabilistic temporal logic that can express a range of quantitative
properties of these models, relating to the probability of an event's
occurrence or the expected value of a reward measure. We then propose
techniques to either verify that such a property holds or to synthesise a
controller for the model which makes it true. Our approach is based on an
integer discretisation of the model's dense-time behaviour and a grid-based
abstraction of the uncountable belief space induced by partial observability.
The latter is necessarily approximate since the underlying problem is
undecidable, however we show how both lower and upper bounds on numerical
results can be generated. We illustrate the effectiveness of the approach by
implementing it in the PRISM model checker and applying it to several case
studies, from the domains of computer security and task scheduling
Using genetic data to predict the vulnerability of a native predator to a toxic invader
Australia has no native toad species, and as a consequence, many Australian predators lack resistance to the toxins of the invasive cane toad Rhinella marina, and die if they ingest one of these toads. Resistance is conferred by a small and consistent genetic change, so genetic data can provide a rapid, non-invasive way to clarify the vulnerability of as-yet-unstudied taxa. To evaluate the hypothesis that a recent decline of ghost bat Macroderma gigas populations in tropical Australia is due to ingestion of cane toads, we sequenced the H1-H2 extracellular domain of the sodium-potassium-ATPase. Two anuran-eating Asian relatives of the Australian species possess the genes that confer bufotoxin resistance, but the ghost bat does not. Like varanid lizards (major victims of the toad invasion), Australian ghost bats appear to have lost their physiological resistance to toad toxins but retained generalist foraging behaviours, potentially including a readiness to attack toads as well as frogs. Our genetic data suggest that cane toads may imperil populations of this iconic predator, and detailed behavioural and ecological studies are warranted.Richard Shine, Supen Wang, George Madani, Kyle N. Armstrong, Libiao Zhang, Yi-Ming L
Influencia de diferentes regímenes de riego y tiempo de siembra en la calidad y cantidad del cáliz, el contenido de aceite de las semillas y la eficiencia del uso del agua de la roselle (Hibiscus sabdariffa L.)
This study was carried out to examine the physiological traits, quality of calyx extract and seed oil content of roselle (Hibiscus sabdariffa L.) as affected by irrigation regimes and planting dates. The growth period from seed sowing to calyx harvesting was shortened as planting time was delayed. Stem diameter and plant height were decreased by drought stress or late planting, but calyx yield, total phenolic content, total anthocyanin content, vitamin C, and calyx water use efficiency increased under mild drought condition. In addition, antioxidant activity and calyx water use efficiency were significantly increased by late planting. It was suggested that an increase in calyx harvest index in delay in planting would be due to better photosynthesis activity and higher assimilate use efficiency because of the increase in sink capacity. Seed oil content decreased considerably due to drought stress and delay in planting date. These findings suggest that mild drought stress improves the quality and quantity of calyx and water use efficiency.Este estudio se llevó a cabo para examinar los rasgos fisiológicos, la calidad del extracto de cáliz y el contenido de aceite de semillas de roselle (Hibiscus sabdariffa L.) afectado por regímenes de riego y fecha de siembra. El período de crecimiento desde la siembra de la semilla hasta la cosecha del cáliz se acortó debido a que se retrasó el tiempo de siembra. El diámetro del tallo y la altura de la planta disminuyeron por el estrés por sequía o la siembra tardía, pero el rendimiento del cáliz, el contenido fenólico total, el contenido total de antocianinas, la vitamina C y la eficiencia del uso del agua del cáliz aumentaron en condiciones de sequía leve. Además, la actividad antioxidante y la eficiencia del uso del agua del cáliz aumentaron significativamente en la siembra tardía. Se sugirió que el aumento del índice de cosecha del cáliz en la demora en la siembra se debería a una mejor actividad de fotosíntesis y una mayor eficiencia en el uso de asimilación debido al aumento de la capacidad de hundimiento. El contenido de aceite de las semillas disminuyó considerablemente debido al estrés por sequía y al retraso en la fecha de siembra. Estos hallazgos sugieren que el estrés por sequía leve mejora la calidad y cantidad del cáliz y la eficiencia del uso del agua
A semi-autonomous generic network for seamless personalised services at home and elsewhere
The ePerSpace project is creating an open, interoperable and trusted semi-autonomous (hybrid) generic distributed networked system, with content adaptation and service platform management, in which home and personal devices can seamlessly work together to provide personalised services. This paper will present the main concept and components of the system, including a Global Service Manager, Local Service Manager, and the user and residential gateways, and it will give an overview of services run on this global service platform
Chlamydia trachomatis in women with full-term deliveries and women with abortion
Problem statement: There are some documents which support the role of some certain infections such as Chlamydia trachomatis in spontaneous abortion. As there were not data about role this bacterium in abortion in this area of IRAN, this study was conducted to evaluate the prevalence of Chlamydia trachomatis in women with abortion and compare it with healthy women with no previous history of abortion. Approach: This case-control study was carried out in Shariatee hospital of Hormozgan University of medical sciences, during 2004-2005. A number of 220 women with definite diagnosis of previous abortion and 200 matched women with normal full term delivery and negative history of miscarriage as controls were studied as case and control groups. All obtained PAP smears from the case and the control groups were then tested using Immunoflourescent method for detection of Chlamydia trachomatis. Data was analyzed, using SPSS software (chi square and t-test). Results: The prevalence of positive direct immunofluorescent test on PAP smears indicating the presence of Chlamydia trachomatis was 56 (25.45) in women with abortion comparing to 13 (5.20) in women in control group, the difference was significant (p = 0.0001). Conclusion: This study showed Chlamydia trachomatis is an important causative agent for abortion in this area of IRAN. © 2010 Science Publications
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