987 resultados para Panthera leo
Resumo:
A 14-year-old male Siberian tiger (Panthera tigris altaica) was admitted with an ulcerating mass on the right thoracic wall. Radiographic and computed tomographic evaluation indicated 2 isolated cutaneous masses without any signs of metastasis. Histology of a Tru-Cut biopsy revealed an anaplastic sarcoma with giant cells. Both tumors were resected with appropriate normal tissue margins. The size of the defect did not allow primary closure of the wound; therefore, a mesh expansion technique was attempted. Three months later, the tiger had to be euthanized due to extensive metastasis to the lungs. Histomorphological features and immunohistochemical results confirmed the diagnosis of malignant peripheral nerve sheath tumor. In contrast to domestic animal experience, the tumor had spread extensively to the lungs without local reccurrence in a short period of time. Correct diagnosis requires various immunohistochemical evaluations of the tumor tissue.
Resumo:
Space Based Solar Power satellites use solar arrays to generate clean, green, and renewable electricity in space and transmit it to earth via microwave, radiowave or laser beams to corresponding receivers (ground stations). These traditionally are large structures orbiting around earth at the geo-synchronous altitude. This thesis introduces a new architecture for a Space Based Solar Power satellite constellation. The proposed concept reduces the high cost involved in the construction of the space satellite and in the multiple launches to the geo-synchronous altitude. The proposed concept is a constellation of Low Earth Orbit satellites that are smaller in size than the conventional system. For this application a Repeated Sun-Synchronous Track Circular Orbit is considered (RSSTO). In these orbits, the spacecraft re-visits the same locations on earth periodically every given desired number of days with the line of nodes of the spacecraft’s orbit fixed relative to the Sun. A wide range of solutions are studied, and, in this thesis, a two-orbit constellation design is chosen and simulated. The number of satellites is chosen based on the electric power demands in a given set of global cities. The orbits of the satellites are designed such that their ground tracks visit a maximum number of ground stations during the revisit period. In the simulation, the locations of the ground stations are chosen close to big cities, in USA and worldwide, so that the space power constellation beams down power directly to locations of high electric power demands. The j2 perturbations are included in the mathematical model used in orbit design. The Coverage time of each spacecraft over a ground site and the gap time between two consecutive spacecrafts visiting a ground site are simulated in order to evaluate the coverage continuity of the proposed solar power constellation. It has been observed from simulations that there always periods in which s spacecraft does not communicate with any ground station. For this reason, it is suggested that each satellite in the constellation be equipped with power storage components so that it can store power for later transmission. This thesis presents a method for designing the solar power constellation orbits such that the number of ground stations visited during the given revisit period is maximized. This leads to maximizing the power transmission to ground stations.
Resumo:
Der Beitrag vergleicht die Grundzüge des Totenkults um Albert Leo Schlageter in der Weimarer Republik und im Nationalsozialismus. Der Fokus der Untersuchung liegt auf dem Medieneinsatz, der den nationalsozialistischen Märtyrerkult vom Totengedenken in der Weimarer Republik unterscheidet. Die verschiedenen Ebenen der Medialisierung werden abschließend an einem konkreten Fallbeispiel, dem Schlageter-Gedenken auf der Zugspitze, demonstriert.
Resumo:
Particulate scattering and backscattering are two quantities that have traditionally been used to quantify in situ particulate concentration. The ratio of the backscattering by particles to total scattering by particles (the particulate backscattering ratio) is weakly dependent on concentration and therefore provides us with information on the characteristics of the particulate material, such as the index of refraction. The index of refraction is an indicator of the bulk particulate composition, as inorganic minerals have high indices of refraction relative to oceanic organic particles such as phytoplankton and detrital material that typically have a high water content. We use measurements collected near the Rutgers University Long-term Ecosystem Observatory in 15 m of water in the Mid-Atlantic Bight to examine application of the backscattering ratio. Using four different instruments, the HOBILabs Hydroscat-6, the WETLabs ac-9 and EcoVSF, and a prototype VSF meter, three estimates of the ratio of the particulate backscattering ratio were obtained and found to compare well. This is remarkable because these are new instruments with large differences in design and calibration. The backscattering ratio is used to map different types of particles in the nearshore region, suggesting that it may act as a tracer of water movement. We find a significant relationship between the backscattering ratio and the ratio of chlorophyll to beam attenuation. This implies that these more traditional measurements may be used to identify when phytoplankton or inorganic particles dominate. In addition, it provides an independent confirmation of the link between the backscattering ratio and the bulk composition of particles.