453 research outputs found
Simulating anthropogenic impacts to bird communities in tropical rain forests
We used an aggregated modelling approach to simulate the impacts ofanthropogenic disturbances on the long-term dynamics of faunal diversityin tropical rain forests. We restricted our study to bird communities eventhough the approach is more general. We developed a model calledBIODIV which simulated the establishment of hypothetical bird speciesin a forest. Our model was based on the results of a simple matrix modelwhich calculated the spatio-temporal dynamics of a tropical rain forest inMalaysia. We analysed the establishment of bird species in a secondaryforest succession and the impacts of 60 different logging scenarios on thediversity of the bird community. Of the three logging parameters(cycle length, method, intensity), logging intensity had the most servereimpact on the bird community. In the worst case the number of bird specieswas reduced to 23% of the species richness found in a primary forest
Spacecraft applications of advanced global positioning system technology
The purpose of this study was to evaluate potential uses of Global Positioning System (GPS) in spacecraft applications in the following areas: attitude control and tracking; structural control; traffic control; and time base definition (synchronization). Each of these functions are addressed. Also addressed are the hardware related issues concerning the application of GPS technology and comparisons are provided with alternative instrumentation methods for specific functions required for an advanced low earth orbit spacecraft
Enhancement of fluorescent properties of near-infrared dyes using clickable oligoglycerol dendrons
Near-infrared (NIR) fluorescent dyes are gaining increased attention due to
their potential to serve as molecular probes for in vivo imaging. Here, we
demonstrate that oligoglycerol dendrons effectively enhance the fluorescence
properties of an NIR dye by increasing the solubility in water and the
prevention of aggregate formation. First- and second-generation oligoglycerol
dendrons were conjugated to an NIR dye via a dipolar-cycloaddition (click)
reaction. The two new dye conjugates exhibited enhanced NIR fluorescent
emission and considerably higher fluorescent quantum yields than the dye
alone. The high photostability measured for one of the oligoglycerol-linked
dyes, in comparison to commonly used fluorogenic dyes such as Cy5 and Cy7, was
validated using fluorescence microscopy of macrophages
Мониторинг опасных геологических процессов на территории г. Томска
International audienceTo assess the accuracy and signal quality of axial length measurements by partial coherence laser interferometry (PCI) for optical biometry in eyes with conventional (SO) or heavy silicone oil (HSO) as endotamponade
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Egg: An Extensible and Economics-Inspired Open Grid Computing Platform
The Egg project provides a vision and implementation of how heterogeneous computational requirements will be supported within a single grid and a compelling reason to explain why computational grids will thrive. Environment computing, which allows a user to specify properties that a compute environment must satisfy in order to support the user’s computation, provides a how. Economic principles, allowing resource owners, users, and other stakeholders to make value and policy statements, provides a why. The Egg project introduces a language for defining software environments (egg shell), a general type for grid objects (the cache), and a currency (the egg). The Egg platform resembles an economically driven Internetwide Unix system with egg shell playing the role of a scripting language and caches playing the role of a global file system, including an initial collection of devices.Engineering and Applied Science
Consensus recommendations for the diagnosis and treatment of acquired hemophilia A
<p>Abstract</p> <p>Background</p> <p>Acquired hemophilia A (AHA) is a rare bleeding disorder caused by an autoantibody to coagulation factor (F) VIII. It is characterized by soft tissue bleeding in patients without a personal or family history of bleeding. Bleeding is variable, ranging from acute, life-threatening hemorrhage, with 9-22% mortality, to mild bleeding that requires no treatment. AHA usually presents to clinicians without prior experience of the disease, therefore diagnosis is frequently delayed and bleeds under treated.</p> <p>Methods</p> <p>Structured literature searches were used to support expert opinion in the development of recommendations for the management of patients with AHA.</p> <p>Results</p> <p>Immediate consultation with a hemophilia center experienced in the management of inhibitors is essential to ensure accurate diagnosis and appropriate treatment. The laboratory finding of prolonged activated partial thromboplastin time with normal prothrombin time is typical of AHA, and the diagnosis should be considered even in the absence of bleeding. The FVIII level and autoantibody titer are not reliable predictors of bleeding risk or response to treatment. Most patients with AHA are elderly; comorbidities and underlying conditions found in 50% of patients often influence the clinical picture. Initial treatment involves the control of acute bleeding with bypassing agents. Immunosuppressive treatment to eradicate the FVIII inhibitor should be started as soon as the diagnosis is confirmed to reduce the time the patient is at risk of bleeding.</p> <p>Conclusions</p> <p>These recommendations aim to increase awareness of this disorder among clinicians in a wide range of specialties and provide practical advice on diagnosis and treatment.</p
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