7,008 research outputs found
Marine mammal strandings: technical control on site
Strandings of marine mammals are always an unusual occurrence. Whether the animals are living or dead, these events require the input of many services and people. Techniques can be implemented to protect the animals, stabilise them, transport them, or -when they are dead- dispose of them properly. Technical coordination on the beach is therefore an important factor for success. The paper examines the various possible types of strandings and the different methods of intervention
Circadian Rhythms, Neuroanatomy Of The Superchiasmatic Nucleus And Selective Breeding Of The Northern Red -Backed Vole (Clethrionomys Rutilus)
Thesis (Ph.D.) University of Alaska Fairbanks, 2007The experiments performed in this thesis investigated the circadian rhythms and neuroanatomy of a subarctic rodent, the northern red-backed vole ( Clethrionomys rutilus). Arctic and subarctic light regimes are extreme, with long periods of light and dark and large daily changes in day-length, but very little is known about circadian rhythms of mammals at high latitudes. A colony of C. rutilus was established and proper husbandry techniques were developed to allow voles to reproduce in captivity. Wild-caught and laboratory reared animals were tested for circadian rhythms in a 16:8 hour light:dark (LD) cycle, constant dark (DD) and constant light (LL). Voles displayed predominantly nocturnal patterns of wheel-running in 16:8 LD. In LL and DD, animals displayed large phenotypic variation in circadian rhythms with many becoming non-circadian (60% in DD, 72% in LL), indicating highly labile circadian organization. The distributions of eight common neurotransmitters in the suprachiasmatic nucleus (SCN), the brain's master circadian clock, were characterized. The SCN of C. rutilus is similar to that found in other rodents. Larger quantities of cholecystokinin and neuropeptide Y are found in the SCN of C. rutilus pointing to the possible importance of non-photic cues in resetting the phase of the internal clock. An additional study also found a distinct distribution of Substance P fibers and neurokinin-1 receptors in the SCN of C. rutilus. Starting with the 5th generation, laboratory-bred voles were selectively bred to create two lines of voles that maintained a circadian rhythm in DD, two lines that lost their circadian rhythm in DD, and a randomly bred control line. After three additional generations no significant differences were found among the lines due to the variability in the response to selection over the first few generations. With a large phenotypic variation in circadian wheel-running rhythms and an SCN similar to other rodents studied, C. rutilus is an ideal candidate to study subarctic circadian adaptations. Continued selective breeding will develop a useful tool for elucidating natural genetic variation in circadian rhythm characteristics in a subarctic mammal
Multi-domain service orchestration over networks and clouds: a unified approach
End-to-end service delivery often includes transparently inserted Network Functions (NFs) in the path. Flexible service chaining will require dynamic instantiation of both NFs and traffic forwarding overlays. Virtualization techniques in compute and networking, like cloud and Software Defined Networking (SDN), promise such flexibility for service providers. However, patching together existing cloud and network control mechanisms necessarily puts one over the above, e.g., OpenDaylight under an OpenStack controller. We designed and implemented a joint cloud and network resource virtualization and programming API. In this demonstration, we show that our abstraction is capable for flexible service chaining control over any technology domain
Accuracy of the Hartree-Fock method for Wigner molecules at high magnetic fields
Few-electron systems confined in two-dimensional parabolic quantum dots at
high magnetic fields are studied by the Hartree-Fock (HF) and exact
diagonalization methods. A generalized multicenter Gaussian basis is proposed
in the HF method. A comparison of the HF and exact results allows us to discuss
the relevance of the symmetry of the charge density distribution for the
accuracy of the HF method. It is shown that the energy estimates obtained with
the broken-symmetry HF wave functions become exact in the infinite
magnetic-field limit. In this limit the charge density of the broken-symmetry
solution can be identified with the classical charge distribution.Comment: to appear in EPJ
Deploying elastic routing capability in an SDN/NFV-enabled environment
SDN and NFV are two paradigms that introduce unseen flexibility in telecom networks. Where previously telecom services were provided by dedicated hardware and associated (vendor-specific) protocols, SDN enables to control telecom networks through specialized software running on controllers. NFV enables highly optimized packet-processing network functions to run on generic/multi-purpose hardware such as x86 servers. Although the possibilities of SDN and NFV are well-known, concrete control and orchestration architectures are still under design and few prototype validations are available. In this demo we demonstrate the dynamic up-and downscaling of an elastic router supporting NFV-based network management, for example needed in a VPN service. The framework which enables this elasticity is the UNIFY ESCAPE environment, which is a PoC following an ETSI NFV MANO-conform architecture. This demo is one of the first to demonstrate a fully closed control loop for scaling NFs in an SDN/NFV control and orchestration architecture
Embedded Software V&V using Virtual Platforms for Powertrain applications
International audienceCurrent development trends for automotive products are driven by time to market reduction, cost optimization, and quality improvement. Dual to these business constraints are demands for innovation and safety conformance which impose increasing complexity on embedded systems. To address these challenges impacting software and hardware to improve system dependability, new methodology and tools need to be set-up. The use of representative virtual platforms combining speed and accuracy allows earlier software development, improved system testing, and fault injection analysis, with a high potential for reuse of system IPs (including both hardware and software). In this paper, we will present investigation on new methods and associated results using a simplified virtual platform to test a powertrain application
Microborings in mid Cretaceous fish teeth
Fish teeth and other remains from the British Cretaceous contain abundant evidence for post-mortem colonization by endolithic organisms. The borings are here recognised as occurring in three morphotypes, including a flask-shaped form not previously recorded. There is strong evidence to suggest that each of these boring types shows a strong preference for a particular substrate histology. The damage and destruction of vertebrate remains by microborings is here considered to exert a major taphonomic control on microvertebrate assemblages. The relationships between the intensity of colonization of vertebrate material by endolithic organisms and palaeoenvironment have implications for using these bone microborings as palaeoenvironmental indicators
Thermoelectric Processes and Materials
Contains reports on three research projects.United States Navy, Office of Naval Research (Contract Nonr-1841(51)
GDP Per Capita Measured in Purchasing Power Standard: an Analysis of Results
Eurostat regularly issues GDP per capita statistics in purchasing power standards, for member countries of the European Union. This paper aims at recalling the main methodological elements used in order to compute these statistics, at presenting their interest and their limits. We highlight the main conclusions that can be drawn from them.GDP measurement, purchasing power standard, European Union
Thermoelectric Processes and Materials
Contains reports on three research projects.United States Navy, Office of Naval Research (Contract Nonr-1841(51)
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