99 research outputs found
Boundedness, compactness and Schatten-class membership of weighted composition operators
The boundedness and compactness of weighted composition operators on the
Hardy space of the unit disc is analysed. Particular reference
is made to the case when the self-map of the disc is an inner function.
Schatten-class membership is also considered; as a result, stronger forms of
the two main results of a recent paper of Gunatillake are derived. Finally,
weighted composition operators on weighted Bergman spaces are considered, and the results of Harper and Smith,
linking their properties to those of Carleson embeddings, are extended to this
situation.Comment: 12 page
A Mathematical Model of Liver Cell Aggregation In Vitro
The behavior of mammalian cells within three-dimensional structures is an area of intense biological research and underpins the efforts of tissue engineers to regenerate human tissues for clinical applications. In the particular case of hepatocytes (liver cells), the formation of spheroidal multicellular aggregates has been shown to improve cell viability and functionality compared to traditional monolayer culture techniques. We propose a simple mathematical model for the early stages of this aggregation process, when cell clusters form on the surface of the extracellular matrix (ECM) layer on which they are seeded. We focus on interactions between the cells and the viscoelastic ECM substrate. Governing equations for the cells, culture medium, and ECM are derived using the principles of mass and momentum balance. The model is then reduced to a system of four partial differential equations, which are investigated analytically and numerically. The model predicts that provided cells are seeded at a suitable density, aggregates with clearly defined boundaries and a spatially uniform cell density on the interior will form. While the mechanical properties of the ECM do not appear to have a significant effect, strong cell-ECM interactions can inhibit, or possibly prevent, the formation of aggregates. The paper concludes with a discussion of our key findings and suggestions for future work
Characterization of bone repair in rat femur after treatment with calcium phosphate cement and autogenous bone graft
<p>Abstract</p> <p>Background</p> <p>In this study, the biocompatibility, stability and osteotransductivity of a new cement based on alpha-tricalcium phosphate (alpha-TCP) were investigated in a bone repair model using a rat model.</p> <p>Methods</p> <p>The potential of alpha-TCP on bone repair was compared to autogenous bone grafting, and unfilled cavities were used as negative control. Surgical cavities were prepared and designated as test (T), implanted with alpha-TCP blocks; negative control (C - ), unfilled; and positive control (C + ), implanted with autogenous bone graft. Results were analyzed on postoperative days three, seven, 14, 21 and 60.</p> <p>Results</p> <p>The histological analyses showed the following results. Postoperative day three: presence of inflammatory infiltrate, erythrocytes and proliferating fibroblasts in T, C - and C + samples. Day seven: extensive bone neoformation in groups T and C + , and beginning of alpha-TCP resorption by phagocytic cells. Days 14 and 21: osteoblastic activity in the three types of cavities. Day 60: In all samples, neoformed bone similar to surrounding bone. Moderate interruption on the ostectomized cortical bone.</p> <p>Conclusions</p> <p>Bone neoformation is seen seven days after implantation of alpha-TCP and autogenous bone. Comparison of C - with T and C + samples showed that repair is faster in implanted cavities; on day 60, control groups presented almost complete bone repair. Alpha-TCP cement presents biocompatibility and osteotransductivity, besides stability, but 60 days after surgery the cavities were not closed.</p
Investigation of Physical Properties of a Polycaprolactone Dermal Filler when Mixed with Lidocaine and Lidocaine/Epinephrine
Embedding consumer and community involvement within an established research centre: moving from general recommendations to an actionable framework
Background: The value of involving consumers and community members in every stage of the research process is gaining recognition as an important consideration in the wider research landscape. The National Health and Medical Research Council (NHMRC) has provided general recommendations for involving consumers and community members in research, although the translation of these recommendations into tangible actions has not yet been well defined. In light of these recommendations, many research institutions are now seeking to incorporate the voices of consumers and community members in their research practices.
Methods: The consumer and community involvement framework described in this paper incorporates the NHMRC’s recommendations to produce a four-tiered model where consumer participants nominate their level of involvement depending on their research interests and preferred level of commitment. In ascending order, the tiers are: Consumer Subscriber, Document Reviewer, Research Buddy and Consumer Advocate.
The success of this framework depends upon the implementation of effective governance and access to appropriate infrastructure. A Consumer and Community Advisory Group and a designated Consumer and Community Liaison Officer will take responsibility for ensuring appropriate interactions between consumers, researchers, and the research center’s executive team. The framework aims to apply suitable support structures in place to manage expectations and minimize barriers to effective involvement, whilst ensuring that consumer contributions are appropriately valued and incorporated in the research.
Discussion: Involving consumers and community members in the research process is an important step towards developing and delivering effective, person-centered health care. While consumer and community involvement offer researchers invaluable perspectives on their research program, it provides an opportunity for consumers and community members to be actively involved in health research and improve the health and wellbeing for those living with health conditions
Road agency practices. Part B., External consultation for road strategy development
http://trove.nla.gov.au/work/2486660
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