1,278 research outputs found

    The Collective Consciousness of Information Technology Research: Ways of seeing Information Technology Research: Its Objects and Territories

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    The collective consciousness of effective groups of researchers is characterised by shared understandings of their research object or territory. In the relatively new field of information technology research, rapid expansion and fragmentation of the territory has led to different perceptions about what constitutes information technology research. This project explores a facet of the collective consciousness of disparate groups of researchers and lays a foundation for constructing shared research objects. Making IT researchersā€™ ways of seeing explicit may help us understand some of the complexities associated with inter and intra disciplinary collaboration amongst research groups, and the complexities associated with technology transfer to industry. This report analyses IT research, its objects and territories, as they are constituted by IT researchers associated with the sub-disciplines of information systems, computer science and information security. A phenomenographic approach is used to elicit data from a diverse range of IT researchers in semistructured interviews. This data is analysed to show (1) the variation in meaning associated with the idea of IT research and (2) the awareness structures through which participants experience variation in ways of seeing the object and territories of IT research. An Outcome Space represents the interrelation between different ways of seeing the territory. Eight ways of seeing IT research, its objects and territories, were found: The Technology Conception, The Information Conception, The Information and Technology Conception, The Communication Conception, The Ubiquitous Conception, The Sanctioned Conception, The Dialectic Conception and The Constructed Conception. These are described in detail and illustrated with participantsā€™ quotes. Finally, some recommendations for further research are made

    The collective consciousness of Information Technology research: The significance and value of research projects. A. The views of IT researchers

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    This research seeks to reveal the different perceptual worlds in a research community, with the longterm intent of fostering increased understanding and hence collaboration. In the relatively new field of information technology (IT) research, available evidence suggests that a shared understanding of the research object or territory does not yet exist. This has led to the development of different perceptions amongst IT researchers of what constitutes significant and valuable research. A phenomenological approach is used to elicit data from a diverse range of IT researchers in semistructured interviews. This data is presented to show (1) the variation in meaning associated with the idea of significance and value and (2) the awareness structures through which participants experience significance and value. An Outcome Space represents the interrelation between those different ways of seeing, revealing a widening awareness. Five categories of ways of seeing the significance and value of research projects were found: The Personal Goals Conception, The Research Currency Conception, The Design of the Research Project Conception, The Outcomes for the Technology End User Conception and The Solving Real-World Problems Conception. These are situated within three wider perceptual boundaries: The Individual, The Research Community and Humankind. The categories are described in detail, demonstrated with participantsā€™ quotes and illustrated with diagrams. A tentative comparison is made between this project and a similar investigation of IT professionalsā€™ ways of seeing the significance and value of IT research projects. Finally, some recommendations for further research are made

    The collective consciousness of Information Technology research: The significance and value of research projects. B. The views of IT industry professionals

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    This research seeks to reveal the different perceptual worlds in a research community, with the longterm intent of fostering increased understanding and hence collaboration. In the relatively new field of information technology (IT) research, available evidence suggests that a shared understanding of the research object or territory does not yet exist. This has led to the development of different perceptions amongst IT researchers of what constitutes significant and valuable research. Phenomenological methodology is used to elicit data from a diverse range of IT industry professionals in semi-structured interviews. This data is presented to show (1) the variation in meaning associated with the idea of significance and value and (2) the awareness structures through which participants experience significance and value. An Outcome Space represents the interrelation between those different ways of seeing, revealing a widening awareness. Five categories of ways of seeing the significance and value of research projects were found: The Personal Goals Conception, The Commercial Goals Conception, The Outcomes for the Technology End User Conception, The Solving Real-World Problems Conception and The Design of the Research Project Conception. These are situated within three wider perceptual boundaries: The Individual, The Enterprise and Society. The categories are described in detail, demonstrated with participantsā€™ quotes and illustrated with diagrams. A tentative comparison is made between this project and a similar investigation of IT researchersā€™ ways of seeing the significance and value of IT research projects. Finally, some recommendations for further research are made

    Real-Time Microsensor Measurement of Local Metabolic Activities in Ex Vivo Dental Biofilms Exposed to Sucrose and Treated with Chlorhexidine

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    Dental biofilms are characterized by structural and functional heterogeneity. Due to bacterial metabolism, gradients develop and diverse ecological microniches exist. The aims of this study were (i) to determine the metabolic activity of microorganisms in naturally grown dental biofilms ex vivo by measuring dissolved oxygen (DO) and pH profiles with microelectrodes with high spatial resolution and (ii) to analyze the impact of an antimicrobial chlorhexidine (CHX) treatment on microbial physiology during stimulation by sucrose in real time. Biofilms were cultivated on standardized human enamel surfaces in vivo. DO and pH profiles were measured in a flow cell system in sterile human saliva, after sucrose addition (10%), again after alternative treatment of the sucrose exposed biofilms with CHX (0.2%) for 1 or 10 min or after being killed with paraformaldehyde (4%). Biofilm structure was visualized by vitality staining with confocal microscopy. With saliva as the sole nutrient source oxygen consumption was high within the superficial biofilm layers rendering deeper layers (>220 Ī¼m) anoxic. Sucrose addition induced the thickness of the anaerobic zone to increase with a concurrent decrease in pH (7.1 to 4.4). CHX exposure reduced metabolic activity and microbial viability at the biofilm surface and drove metabolic activity deeper into the biofilm. CHX treatment led to a reduced viability at the biofilm surface with minor influence on overall biofilm physiology after 1 min; even after 10 min there was measurable respiration and fermentation inside the biofilm. However, the local microenvironment was more aerated, less acidogenic, and presumably less pathogenic

    Cephalosporin-3ā€™-diazeniumdiolate NO-donor prodrug PYRRO-C3D enhances azithromycin susceptibility of non-typeable Haemophilus influenzae biofilms

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Objectives: PYRRO-C3D is a cephalosporin-3-diazeniumdiolate nitric oxide (NO)-donor prodrug designed to selectively deliver NO to bacterial infection sites. The objective of this study was to assess the activity of PYRRO-C3D against non-typeable Haemophilus influenzae (NTHi) biofilms and examine the role of NO in reducing biofilm-associated antibiotic tolerance. Methods: The activity of PYRRO-C3D on in vitro NTHi biofilms was assessed through CFU enumeration and confocal microscopy. NO release measurements were performed using an ISO-NO probe. NTHi biofilms grown on primary ciliated respiratory epithelia at an air-liquid interface were used to investigate the effects of PYRRO-C3D in the presence of host tissue. Label-free LC/MS proteomic analyses were performed to identify differentially expressed proteins following NO treatment. Results: PYRRO-C3D specifically released NO in the presence of NTHi, while no evidence of spontaneous NO release was observed when the compound was exposed to primary epithelial cells. NTHi lacking Ī²-lactamase activity failed to trigger NO release. Treatment significantly increased the susceptibility of in vitro NTHi biofilms to azithromycin, causing a log-fold reduction in viability (p<0.05) relative to azithromycin alone. The response was more pronounced for biofilms grown on primary respiratory epithelia, where a 2-log reduction was observed (p<0.01). Label-free proteomics showed that NO increased expression of sixteen proteins involved in metabolic and transcriptional/translational functions. Conclusions: NO release from PYRRO-C3D enhances the efficacy of azithromycin against NTHi biofilms, putatively via modulation of NTHi metabolic activity. Adjunctive therapy with NO mediated through PYRRO-C3D represents a promising approach for reducing biofilm associated antibiotic tolerance

    Hydrodynamic dispersion within porous biofilms

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    Many microorganisms live within surface-associated consortia, termed biofilms, that can form intricate porous structures interspersed with a network of fluid channels. In such systems, transport phenomena, including flow and advection, regulate various aspects of cell behavior by controlling nutrient supply, evacuation of waste products, and permeation of antimicrobial agents. This study presents multiscale analysis of solute transport in these porous biofilms. We start our analysis with a channel-scale description of mass transport and use the method of volume averaging to derive a set of homogenized equations at the biofilm-scale in the case where the width of the channels is significantly smaller than the thickness of the biofilm. We show that solute transport may be described via two coupled partial differential equations or telegrapher's equations for the averaged concentrations. These models are particularly relevant for chemicals, such as some antimicrobial agents, that penetrate cell clusters very slowly. In most cases, especially for nutrients, solute penetration is faster, and transport can be described via an advection-dispersion equation. In this simpler case, the effective diffusion is characterized by a second-order tensor whose components depend on (1) the topology of the channels' network; (2) the solute's diffusion coefficients in the fluid and the cell clusters; (3) hydrodynamic dispersion effects; and (4) an additional dispersion term intrinsic to the two-phase configuration. Although solute transport in biofilms is commonly thought to be diffusion dominated, this analysis shows that hydrodynamic dispersion effects may significantly contribute to transport

    Cerebellar Integrity in the Amyotrophic Lateral Sclerosis - Frontotemporal Dementia Continuum

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    Amyotrophic lateral sclerosis (ALS) and behavioural variant frontotemporal dementia (bvFTD) are multisystem neurodegenerative disorders that manifest overlapping cognitive, neuropsychiatric and motor features. The cerebellum has long been known to be crucial for intact motor function although emerging evidence over the past decade has attributed cognitive and neuropsychiatric processes to this structure. The current study set out i) to establish the integrity of cerebellar subregions in the amyotrophic lateral sclerosis-behavioural variant frontotemporal dementia spectrum (ALS-bvFTD) and ii) determine whether specific cerebellar atrophy regions are associated with cognitive, neuropsychiatric and motor symptoms in the patients. Seventy-eight patients diagnosed with ALS, ALS-bvFTD, behavioural variant frontotemporal dementia (bvFTD), most without C9ORF72 gene abnormalities, and healthy controls were investigated. Participants underwent cognitive, neuropsychiatric and functional evaluation as well as structural imaging using voxel-based morphometry (VBM) to examine the grey matter subregions of the cerebellar lobules, vermis and crus. VBM analyses revealed: i) significant grey matter atrophy in the cerebellum across the whole ALS-bvFTD continuum; ii) atrophy predominantly of the superior cerebellum and crus in bvFTD patients, atrophy of the inferior cerebellum and vermis in ALS patients, while ALS-bvFTD patients had both patterns of atrophy. Post-hoc covariance analyses revealed that cognitive and neuropsychiatric symptoms were particularly associated with atrophy of the crus and superior lobule, while motor symptoms were more associated with atrophy of the inferior lobules. Taken together, these findings indicate an important role of the cerebellum in the ALS-bvFTD disease spectrum, with all three clinical phenotypes demonstrating specific patterns of subregional atrophy that associated with different symptomology

    New approaches to the treatment of biofilm-related infections

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Bacteria causing chronic infections predominately grow as surface-attached, sessile communities known as biofilms. Biofilm-related infections including cystic fibrosis lung infection, chronic and recurrent otitis media, chronic wounds and implant- and catheter-associated infections, are a significant cause of morbidity and mortality at great financial cost. Chronic biofilm-based infections are recalcitrant to conventional antibiotic therapy and are often unperturbed by host immune responses such as phagocytosis, despite a sustained presence of host inflammation. The diagnosis of clinically important biofilm infections is often difficult as Kochā€™s postulates are rarely met. If treatment is required, surgical removal of the infected implant, or debridement of wound or bone, is the most efficient means of eradicating a clinically significant biofilm. New approaches to treatment are under investigation
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