Effect of the powder characteristics of Sisub3Nsub4 on the microstructure of sintered bodies

Silicon nitride powders sintered with the addition of 2 wt% Mg0 to 95% theoretical density after attrition milling and subsequent purification were evaluated. Preparation of the powders is described. The powder characteristics (specific surfaces, iron concentration, and oxygen content), and density, weight loss, and phase state of the sinter bodies as a function of powder preparation are presented

Tissue Engineering - the gateway to regenerative medicine

Tissue Engineering as an emerging biotechnology sector aims at the in vitro regeneration of diseased tissues and promises to profoundly change medical practice, offering the possibility of regenerating tissues and organs instead of just repairing them (regenerative medicine). Improved healing processes and a higher quality of life are the expected results. This article gives an overview of different technologies for regenerative medicine and presents results of our own current applied research and development. A recent project was successfully closed with the development of a natural biomaterial for soft tissue oral defects. The establishment of an in vitro bioreactor system enabled us to simulate the mechanical and biological environment in a healing wound and to investigate the suitability of different implant materials for the oral tissue regeneration. Moreover, focusing the attention on an alternative method for the intervertebral disc (IVD) regeneration, we established a new tissue engineered approach, based on the three-dimensional (3D) culture of autologous human IVD cells into a polyurethane (PU)-fibrin composite. IVD cells were able to proliferate and, thanks to the 3D conditions, to differentiate expressing the typical native tissue markers. The development of an automated platform was the goal of an additional project, to standardize the cell culture technology, increase the bio-safety and reduce the production costs, moving tissue engineering nearer to clinical application

Drones as a Tool to Monitor Human Impacts and Vegetation Changes in Parks and Protected Areas

Increased visitation to protected areas could have adverse impacts on the conservation values in the protected areas, and therefore effective visitor monitoring methods are needed to meet the complex management challenges that arise. Collecting data on human impacts is highly time consuming, thus requiring more effective tools that allow for high-quality and long-term measurements. In this study, we show how unmanned aerial vehicles (i.e. UAV or drones) could be used to monitor tourism impacts in protected areas. Tourism has boomed in national parks in Norway in recent years, such as in Jotunheimen National Park for which this study applies. We test the use of drones on a site where new tourist facilities will be established to set a baseline to identify future changes. We demonstrate how drones could help protected area management by monitoring visitor use patterns and commonly associated impacts such as trail condition (width and depth), vegetation structure and disturbances, informal trail proliferation, trampling, and trash and other impacts along the trails. We assessed accuracy and reliability compared with intensive field measurements of impacts and found low-cost drones to be effective in mapping the study area with a resolution of 0.5 cm/pixel: drone derived trail measurements were comparable to traditional measurements with a negligible divergence on trail width measurements and a consistent 1.05 cm divergence on trail depth measurements that can be corrected with a few validation points. In addition, we created a high-resolution vegetation classification map that could be used as a baseline for monitoring impacts. We conclude that drones can effectively contribute to visitor monitoring by reducing time spent in the field and by providing high-resolution time series that could be used as baseline to measure tourism impacts on conservation values in protected areas

Scale-dependent response diversity of seabirds to prey in the North Sea

Functional response diversity is defined as the diversity of responses to environmental change among species that contribute to the same ecosystem function. Because different ecological processes dominate on different spatial and temporal scales, response diversity is likely to be scale dependent. Using three extensive data sets on seabirds, pelagic fish, and zooplankton, we investigate the strength and diversity in the response of seabirds to prey in the North Sea over three scales of ecological organization. Two-stage analyses were used to partition the variance in the abundance of predators and prey among the different scales of investigation: variation from year to year, variation among habitats, and variation on the local patch scale. On the year-to-year scale, we found a strong and synchronous response of seabirds to the abundance of prey, resulting in low response diversity. Conversely, as different seabird species were found in habitats dominated by different prey species, we found a high diversity in the response of seabirds to prey on the habitat scale. Finally, on the local patch scale, seabirds were organized in multispecies patches. These patches were weakly associated with patches of prey, resulting in a weak response strength and a low response diversity. We suggest that ecological similarities among seabird species resulted in low response diversity on the year-to-year scale. On the habitat scale, we suggest that high response diversity was due to interspecific competition and niche segregation among seabird species. On the local patch scale, we suggest that facilitation with respect to the detection and accessibility of prey patches resulted in overlapping distribution of seabirds but weak associations with prey. The observed scale dependencies in response strength and diversity have implications for how the seabird community will respond to different environmental disturbances

Inuit Attitudes towards Co-Managing Wildlife in Three Communities in the Kivalliq Region of Nunavut, Canada

We explored Inuit attitudes towards co-managing wildlife in the Kivalliq Region of Nunavut, Canada, working in partnership with the hunters and trappers’ organizations of Igluligaarjuk (Chesterfield Inlet), Tikirarjuaq (Whale Cove), and Qamani’tuaq (Baker Lake). In mixed-methods interviews, study participants in the two coastal communities described dissatisfaction with polar bear (Ursus maritimus) management outcomes, in contrast to a general satisfaction with (or indifference to) the management of other species. Interviewees expressed concern about grizzly bear (Ursus arctos) and, more prominently, caribou (Rangifer tarandus groenlandicus) populations in Qamani’tuaq, the inland community. Researchers have predicted that conflicts specific to polar bear management could lead to regulations being ignored or even defied and endanger the entire system of wildlife co-management. Our results indicate that dissatisfaction over decisions is specific to polar bear management outcomes and does not necessarily apply to the broader system of wildlife co-management. The results suggest that the Nunavut wildlife co-management system is quite functional: polar bear issues aside, Inuit in Qamani’tuaq, Tikirarjuaq, and Igluligaarjuk are largely content with the current functioning of the wildlife co-management regime.Nous avons étudié les attitudes des Inuits à l’égard de la cogestion de la faune dans la région de Kivalliq, au Nunavut, Canada, en collaboration avec les organisations de chasseurs et de trappeurs d’Igluligaarjuk (inlet Chesterfield), de Tikirarjuaq (Whale Cove) et de Qamani’tuaq (Baker Lake). Dans le cadre d’entretiens effectués au moyen de diverses méthodes, les participants à l’étude des deux collectivités côtières ont exprimé leur mécontentement à l’égard des résultats de la gestion de l’ours polaire (Ursus maritimus), comparativement à leur satisfaction générale (ou à leur indifférence) quant à la gestion des autres espèces. Par ailleurs, les personnes interrogées ont exprimé des inquiétudes par rapport aux populations de grizzli (Ursus arctos) et des inquiétudes encore plus grandes par rapport aux populations de caribou (Rangifer tarandus groenlandicus) à Qamani’tuaq, la collectivité intérieure. Selon les chercheurs, les conflits en matière de gestion de l’ours polaire pourraient se traduire par le non-respect ou la non-considération des règlements, et mettre en danger le système de cogestion de la faune dans son ensemble. D’après nos résultats, le mécontentement à l’égard des décisions a précisément trait aux résultats de la gestion des ours polaires et ne concerne pas nécessairement le système général de cogestion de la faune. Selon les résultats, le système de cogestion de la faune du Nunavut est bien fonctionnel : mis à part la question des ours polaires, les Inuits de Qamani’tuaq, de Tikirarjuaq et d’Igluligaarjuk sont en grande partie satisfaits du fonctionnement actuel du régime de cogestion de la faune