53 research outputs found
Mining Social Interaction Data in Virtual Worlds
Virtual worlds and massively multi-player online games are rich sources of information about large-scale teams and groups, offering the tantalizing possibility of harvesting data about group formation, social networks, and network evolution. However these environments lack many of the cues that facilitate natural language processing in other conversational settings and different types of social media. Public chat data often features players who speak simultaneously, use jargon and emoticons, and only erratically adhere to conversational norms. This chapter presents techniques for inferring the existence of social links from unstructured conversational data collected from groups of participants in the Second Life virtual world
Autoinflammatory disease in the lung
Ascertaining the dominant cell type driving an immunological disease is essential to understanding the causal pathology and, therefore, selecting or developing an effective treatment. Classifying immunological diseases in this way has led to successful treatment regimens for many monogenic diseases; however, when the dominant cell type is unclear and there is no obvious causal genetic mutation, then identifying the correct disease classification and appropriate therapy can be challenging. In this review we focus on pulmonary immunological diseases where an innate immune signature has been identified as a predominant aspect of the immunopathology. We describe the molecular pathology of âautoinflammatory diseases of the lungâ and propose that small molecule and biological therapies, including recombinant interleukinâ1 receptor antagonist, that target key innate immune pathways, are likely be beneficial in the control of pulmonary and systemic inflammation in these conditions. In addition, the successful use of macrolide antibiotics to treat lung infections in these conditions further confirms that the innate immune system is the key conductor of inflammation in these pulmonary diseases, as there is a strong body of evidence that macrolides are able to modulate the NLRP3 inflammasome and interleukinâ1β and interleukinâ18 secretion, both of which are central players in the innate immune response. Throughout this review we highlight the published evidence of autoinflammatory disease in chronic obstructive pulmonary disease, bronchiectasis, cystic fibrosis and rheumatoid lung disease and suggest that the fundamental pathology of these diseases places them towards the autoinflammatory pole of the immunological disease continuum
Aryl acylamidase activity exhibited by butyrylcholinesterase is higher in chick than in horse, but much lower than in fetal calf serum.
Several side activities have been attributed to butyrylcholinesterase (BChE), including aryl acylamidase (AAA) activity, which is an amidase-like activity with unknown physiological function splitting the artificial substrate o-nitroacetanilide. For avians, extensive developmental data have pointed to neurogenetic functions of BChE, however, a possible AAA activity of BChE has not been studied. In this study, we first compare the relative levels of AAA exhibited by BChE in whole sera from chick, fetal calves (FCS) and horse. Remarkably, FCS exhibits a 400-fold higher ratio of AAA/BChE than horse and 80-fold higher than chick serum. We then show that an immunoisolated preparation of BChE from chicken serum presents significant activity for AAA. Both in sera and with the purified enzyme, the AAA activity is fully inhibited by anticholinesterase drugs, showing that AAA activity is exclusively conveyed by the BChE molecule. Noticeably, AAA inhibition even occurs at lower drug concentrations than that of BChE activity itself. Moreover, AAA is sensitive to serotonin. These data indicate that (1) AAA is a general feature of serum BChE of vertebrates including avians, (2) AAA is effectively inhibited by cholinergic and serotonergic agents, and (3) AAA may have a developmental role, since it is much pronounced in a serum from fetal animals. Functionally, deamination of neuropeptides, a link between cholinergic and serotonergic neurotransmitter systems, and roles in lipoprotein metabolism could be relevant
Metabolic rates of vascular endothelial cells in vitro
Cultures of endothelial cells and cell lines of endothelial origin were maintained at confluence without medium exchange for a period of 72 h. During this time period the concentration of nutrients - amino acids and glucose - and metabolic waste products - lactate and ammonium - was determined as well as cell vitality and cell numbers. Metabolic rates were calculated and compared for the different cell lines. Surprisingly the primary cells showed significantly higher rates of glucose and glutamine consumption, respectively lactate production than the immortalized cell lines. Except for one tumorigenic cell line all cells showed a significant participation of transaminases in glutamine/ammonium metabolism. Furthermore it could be shown that in routine culture there was no depletion of nutrients or critical accumulation of ammonium or lactate over a culture period of 72 h
Confronting the winds: orientation and flight behaviour of roosting swifts, Apus apus.
Swifts, Apus apus, spend the night aloft and this offers an opportunity to test the degree of adaptability of bird orientation and flight to different ecological situations. We predicted the swifts' behaviour by assuming that they are adapted to minimize energy expenditure during the nocturnal flight and during a compensatory homing flight if they become displaced by wind. We tested the predictions by recording the swifts' altitudes, speeds and directions under different wind conditions with tracking radar; we found an agreement between predictions and observations for orientation behaviour, but not for altitude and speed regulation. The swifts orientated consistently into the head wind, with angular concentration increasing with increasing wind speed. However, contrary to our predictions, they did not select altitudes with slow or moderate winds, nor did they increase their airspeed distinctly when flying into strong head winds. A possible explanation is that their head-wind orientation is sufficient to keep nocturnal displacement from their home area within tolerable limits, leaving flight altitude to be determined by other factors (correlated with temperature), and airspeed to show only a marginal increase in strong winds. The swifts were often moving "backwards", heading straight into the wind but being overpowered by wind speeds exceeding their airspeed. The regular occurrence of such flights is probably uniquely associated with the swifts' remarkable habit of roosting on the wing
Butyrylcholinesterase is complexed with transferrin in chicken serum.
The function of the enzyme butyrylcholinesterase (BChE) both in serum and in brain is unclear. In serum, BChE has been found complexed with several biomedically relevant proteins, with which it could function in concert. Here, the existence of a similar complex formed between BChE and sero-transferrin from adult chicken serum was elucidated. In order to identify both proteins unequivocally, we improved methods to highly purify the 81-kDa BChE and the coisolated 75-kDa transferrin, which then allowed us to tryptically digest and sequence the resulting peptides. The sequences as revealed for BChE peptides were highly identical to mammalian BChEs. A tight complex formation between the two proteins could be established (a) since transferrin is coisolated along with BChE over three steps including procainamide affinity chromatography, while transferrin alone is not bound to this affinity column, and (b) since imunoprecipitation experiments of whole serum with a transferrin-specific antiserum allows us to detect BChE in the precipitate with the BChE-specific monoclonal antibody 7D11. The possible biomedical implications of a complex between transferrin and BChE which here has been shown to exist in chicken serum are briefly discussed
Migration routes and strategies in a highly aerial migrant, the Common Swift Apus apus, revealed by light-level geolocators
The tracking of small avian migrants has only recently become possible by the use of small light-level geolocators, allowing the reconstruction of whole migration routes, as well as timing and speed of migration and identification of wintering areas. Such information is crucial for evaluating theories about migration strategies and pinpointing critical areas for migrants of potential conservation value. Here we report data about migration in the common swift, a highly aerial and long-distance migrating species for which only limited information based on ringing recoveries about migration routes and wintering areas is available. Six individuals were successfully tracked throughout a complete migration cycle from Sweden to Africa and back. The autumn migration followed a similar route in all individuals, with an initial southward movement through Europe followed by a more southwest-bound course through Western Sahara to Sub-Saharan stopovers, before a south-eastward approach to the final wintering areas in the Congo basin. After approximately six months at wintering sites, which shifted in three of the individuals, spring migration commenced in late April towards a restricted stopover area in West Africa in all but one individual that migrated directly towards north from the wintering area. The first part of spring migration involved a crossing of the Gulf of Guinea in those individuals that visited West Africa. Spring migration was generally wind assisted within Africa, while through Europe variable or head winds were encountered. The average detour at about 50% could be explained by the existence of key feeding sites and wind patterns. The common swift adopts a mixed fly-and-forage strategy, facilitated by its favourable aerodynamic design allowing for efficient use of fuel. This strategy allowed swifts to reach average migration speeds well above 300 km/day in spring, which is higher than possible for similar sized passerines. This study demonstrates that new technology may drastically change our views about migration routes and strategies in small birds, as well as showing the unexpected use of very limited geographical areas during migration that may have important consequences for conservation strategies for migrants
Consistency of spatio-temporal patterns of avian migration across the Swiss lowlands
Each year, billions of birds migrate across the continents by day and night through airspaces increasingly altered by human activity, resulting in the deaths of millions of birds every year through collisions with manâmade structures. To reduce these negative impacts on wildlife, forecasts of high migration intensities are needed to apply mitigation actions. While existing weather radar networks offer a unique possibility to monitor and forecast bird migration at large spatial scales, forecasts at the fine spatial scale within a complex terrain, such as the mountainous Swiss landscape, require a smallâscale network of ornithological radars. Before attempting to build such a network, it is crucial to first investigate the consistency of the migratory flow across space and time. In this study, we simultaneously operated three ornithological radar systems across the Swiss lowlands to assess the spatioâtemporal consistency of diurnal and nocturnal bird movements during the spring and autumn migration season. The relative temporal course of migration intensities was generally consistent between sites during peak migration, in particular for nocturnal movements in autumn, but absolute intensities differed greatly between sites. Outside peak migration, bird movement patterns were much less consistent and, unexpectedly, some presumably nonâmigratory bird activity achieved intensities close to peak migration intensities, but without spatial correlations. Only nocturnal migration intensity in autumn could be predicted with consistently high accuracy, but including parameters of atmospheric conditions in the model improved predictability of diurnal movements considerably. Predictions for spring were less reliable, probably because we missed an important part of the migration season. Our results show that reliable forecasts of bird movements within a complex terrain call for a network of yearâround bird monitoring systems, whereas accurate information of atmospheric conditions can help to limit the number of measurement points
An End-to-End QoE Measurement Framework For Immersive 3D Media Delivery Systems
The ROMEO project focuses on the delivery of multiview 3-Dimensional (3D) video enriched with spatial audio on a converged network architecture. Quality of Experience (QoE) modeling plays an important role in several aspects of the overall ROMEO architecture, such as in video compression, multicast tree formation in the P2P overlay, content adaptation and view synthesis. To address various use cases there will be several models of QoE that will be investigated and developed within the scope of the ROMEO project. This paper describes the various models of QoE that will be investigated, specifically, QoE modeling of compression artifacts, rendering artifacts, and packet loss effects on 3D multiview video and QoE factors related to Audio compression and rendering. It is expected that the QoE models developed within the ROMEO project will find important use cases in a wide range of advanced multimedia applications
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