Structural variants of biodegradable polyesterurethane in vivo evoke a cellular and angiogenic response that is dictated by architecture

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2008 Acta Materialia Inc.The aim of this study was to investigate an in vivo tissue response to a biodegradable polyesterurethane, specifically the cellular and angiogenic response evoked by varying implant architectures in a subcutaneous rabbit implant model. A synthetic biodegradable polyesterurethane was synthesized and processed into three different configurations: a non-porous film, a porous mesh and a porous membrane. Glutaraldehyde cross-linked bovine pericardium was used as a control. Sterile polyesterurethane and control samples were implanted subcutaneously in six rabbits (n = 12). The rabbits were killed at 21 and 63 days and the implant sites were sectioned and histologically stained using haemotoxylin and eosin (H&E), Masson’s trichrome, picosirius red and immunostain CD31. The tissue–implant interface thickness was measured from the H&E slides. Stereological techniques were used to quantify the tissue reaction at each time point that included volume fraction of inflammatory cells, fibroblasts, fibrocytes, collagen and the degree of vascularization. Stereological analysis inferred that porous scaffolds with regular topography are better tolerated in vivo compared to non-porous scaffolds, while increasing scaffold porosity promotes angiogenesis and cellular infiltration. The results suggest that this biodegradable polyesterurethane is better tolerated in vivo than the control and that structural variants of biodegradable polyesterurethane in vivo evoke a cellular and angiogenic response that is dictated by architecture.Irish Research Council for Science, Engineering and Technology: funded by the National Development Plan. Enterprise Ireland: Research Innovation Partnership

Modeling highly pathogenic avian influenza transmission in wild birds and poultry in West Bengal, India.

Wild birds are suspected to have played a role in highly pathogenic avian influenza (HPAI) H5N1 outbreaks in West Bengal. Cluster analysis showed that H5N1 was introduced in West Bengal at least 3 times between 2008 and 2010. We simulated the introduction of H5N1 by wild birds and their contact with poultry through a stochastic continuous-time mathematical model. Results showed that reducing contact between wild birds and domestic poultry, and increasing the culling rate of infected domestic poultry communities will reduce the probability of outbreaks. Poultry communities that shared habitat with wild birds or those indistricts with previous outbreaks were more likely to suffer an outbreak. These results indicate that wild birds can introduce HPAI to domestic poultry and that limiting their contact at shared habitats together with swift culling of infected domestic poultry can greatly reduce the likelihood of HPAI outbreaks

Decision making based on quantitative and qualitative evaluations

This study emphasizes mainly on the influence of evaluations, both qualitative and quantitative, on decision making for many occasions that occur in business and technically oriented settings. Decisions made with a certain fuzzy as wen as technical behavior are structured by means of computer-assisted decision-making tools. Decision support tools assist decision makers in making crucial decisions. For instance the tool that has been designed for the purpose of this research will be used for selecting capital-intensive products. It is also intended to prove that with the help of decision support systems decision makers could make decisions by reducing fuzzy decision behavior about capital investments in organizational systems. Such tools consider more than one criterion in making a decision. \u27Me criteria for decision-making will range from the attributes of the system itself to the cost of the system. For each system under consideration for selection, each attribute will be analyzed and rated. Then a cumulative account of all the attributes for each vendor is brought together as a set. Though this set is produced by each decision maker there is little correlation between his decisions and the evaluation of the product. A product\u27s quantitative evaluation may warrant of a different kind of decision than a qualitative evaluation. An evaluation of a system leads to a decision. However when a decision is the one of selection, as is quite often the case, quantitative and qualitative evaluations may be done. Quantitative evaluations generally are performed based on statistical analysis of the system under consideration. A quantitative evaluation may be based also on algorithms designed for specific scenarios. On the other hand a qualitative evaluation may take place in settings that deal with a single system that must be evaluated and it\u27s evaluation recorded in language specific descriptive terms. 11-iis study discusses how decisions can be made using qualitative and quantitative evaluations for the object or situation under consideration