941 resultados para CELL PERFORMANCE
Resumo:
Recent studies on automatic new topic identification in Web search engine user sessions demonstrated that neural networks are successful in automatic new topic identification. However most of this work applied their new topic identification algorithms on data logs from a single search engine. In this study, we investigate whether the application of neural networks for automatic new topic identification are more successful on some search engines than others. Sample data logs from the Norwegian search engine FAST (currently owned by Overture) and Excite are used in this study. Findings of this study suggest that query logs with more topic shifts tend to provide more successful results on shift-based performance measures, whereas logs with more topic continuations tend to provide better results on continuation-based performance measures.
Resumo:
Nanostructured tungsten oxide thin film based gas sensors have been developed by thermal evaporation method to detect CO at low operating temperatures. The influence of Fe-doping and annealing heat treatment on microstructural and gas sensing properties of these films have been investigated. Fe was incorporated in WO3 film by co-evaporation and annealing was performed at 400oC for 2 hours in air. AFM analysis revealed a grain size of about 10-15 nm in all the films. GIXRD analysis showed that as-deposited films are amorphous and annealing at 400oC improved the crystallinity. Raman and XRD analysis indicated that Fe is incorporated in the WO3 matrix as a substitutional impurity, resulting in shorter O-W-O bonds and lattice cell parameters. Doping with Fe contributed significantly towards CO sensing performance of WO3 thin films. A good response to various concentrations (10-1000 ppm) of CO has been achieved with 400oC annealed Fe-doped WO3 film at a low operating temperature of 150oC.
Resumo:
Continuum, partial differential equation models are often used to describe the collective motion of cell populations, with various types of motility represented by the choice of diffusion coefficient, and cell proliferation captured by the source terms. Previously, the choice of diffusion coefficient has been largely arbitrary, with the decision to choose a particular linear or nonlinear form generally based on calibration arguments rather than making any physical connection with the underlying individual-level properties of the cell motility mechanism. In this work we provide a new link between individual-level models, which account for important cell properties such as varying cell shape and volume exclusion, and population-level partial differential equation models. We work in an exclusion process framework, considering aligned, elongated cells that may occupy more than one lattice site, in order to represent populations of agents with different sizes. Three different idealizations of the individual-level mechanism are proposed, and these are connected to three different partial differential equations, each with a different diffusion coefficient; one linear, one nonlinear and degenerate and one nonlinear and nondegenerate. We test the ability of these three models to predict the population level response of a cell spreading problem for both proliferative and nonproliferative cases. We also explore the potential of our models to predict long time travelling wave invasion rates and extend our results to two dimensional spreading and invasion. Our results show that each model can accurately predict density data for nonproliferative systems, but that only one does so for proliferative systems. Hence great care must be taken to predict density data for with varying cell shape.
Resumo:
A fundamental principle of the resource-based (RBV) of the firm is that the basis for a competitive advantage lies primarily in the application of bundles of valuable strategic capabilities and resources at a firm’s or supply chain’s disposal. These capabilities enact research activities and outputs produced by industry funded R&D bodies. Such industry lead innovations are seen as strategic industry resources, because effective utilization of industry innovation capacity by sectors such as the Australian beef industry are critical, if productivity levels are to increase. Academics and practitioners often maintain that dynamic supply chains and innovation capacity are the mechanisms most likely to deliver performance improvements in national industries.. Yet many industries are still failing to capitalise on these strategic resources. In this research, we draw on the resource-based view (RBV) and embryonic research into strategic supply chain capabilities. We investigate how two strategic supply chain capabilities (supply chain performance differential capability and supply chain dynamic capability) influence industry-led innovation capacity utilization and provide superior performance enhancements to the supply chain. In addition, we examine the influence of size of the supply chain operative as a control variable. Results indicate that both small and large supply chain operatives in this industry believe these strategic capabilities influence and function as second-order latent variables of this strategic supply chain resource. Additionally respondents acknowledge size does impacts both the amount of influence these strategic capabilities have and the level of performance enhancement expected by supply chain operatives from utilizing industry-led innovation capacity. Results however also indicate contradiction in this industry and in relation to existing literature when it comes to utilizing such e-resources.
Resumo:
Haematopoiesis is the process by which a hierarchy of mature and progenitor blood cells are formed. These cell populations are all derived from multipotent haematopoietic stem cells (HSC), which reside in the bone marrow ‘niche’ of adult humans. Over the lifetime of a healthy individual, this HSC population replenishes between 1010-1011 blood cells on a daily basis. Dysregulation of this system can lead to a number of haematopoietic diseases, including aplastic anaemias and leukaemias, which result in, or require for disease resolution, bone marrow cell depletion. In 1956, E. Donnall Thomas demonstrated that haematopoiesis could be restored by transplanting bone marrow-derived cells from one man into his identical twin brother, who was suffering from advanced leukaemia. His success drew significant interest in academic research and medicine communities, and 12 years later, the first successful allogeneic transplant was performed. To this day, HSCs remain the most studied and characterised stem cell population. In fact, HSCs are the only stem cell population routinely utilised in the clinic. As such, HSCs function as a model system both for the biological investigation of stem cells, as well as for their clinical application. Herein, we briefly review HSC transplantation, strategies for the ex vivo cultivation of HSCs, recent clinical outcomes, and their impact on the future direction of HSC transplantation therapy.
Resumo:
Thermal-infrared images have superior statistical properties compared with visible-spectrum images in many low-light or no-light scenarios. However, a detailed understanding of feature detector performance in the thermal modality lags behind that of the visible modality. To address this, the first comprehensive study on feature detector performance on thermal-infrared images is conducted. A dataset is presented which explores a total of ten different environments with a range of statistical properties. An investigation is conducted into the effects of several digital and physical image transformations on detector repeatability in these environments. The effect of non-uniformity noise, unique to the thermal modality, is analyzed. The accumulation of sensor non-uniformities beyond the minimum possible level was found to have only a small negative effect. A limiting of feature counts was found to improve the repeatability performance of several detectors. Most other image transformations had predictable effects on feature stability. The best-performing detector varied considerably depending on the nature of the scene and the test.
Resumo:
Is it possible to control identities using performance management systems (PMSs)? This paper explores the theoretical fusion of management accounting and identity studies, providing a synthesised view of control, PMSs and identification processes. It argues that the effective use of PMSs generates a range of obtrusive mechanistic and unobtrusive organic controls that mediate identification processes to achieve a high level of identity congruency between individuals and collectives—groups and organisations. This paper contends that mechanistic control of PMSs provides sensebreaking effects and also creates structural conditions for sensegiving in top-down identification processes. These processes encourage individuals to continue the bottom-up processes of sensemaking, enacting identity and constructing identity narratives. Over time, PMS activities and conversations periodically mediate several episode(s) of identification to connect past, current and future identities. To explore this relationship, the dual locus of control—collectives and individuals—is emphasised to explicate their interplay. This multidisciplinary approach contributes to explaining the multidirectional effects of PMSs in obtrusive as well as unobtrusive ways, in order to control the nature of collectives and individuals in organisations.
Resumo:
This paper explores how the effective use of performance management systems (PMS) essentialises collective identities through the use of textual performances. The discursive effect of PMS operates to simplify members’ logic to allow them to understand and negotiate the complex nature of collective performance. Two case studies, drawing on a qualitative study of the implementation of PMS in two public sector organisations, point to the unique contribution of symbolic effects of one popular PMS, the balanced scorecard (BSC). Findings suggest that the BSC visualising the trajectory of achieving organisational vision through multiple perspectives, measures and linkages is a valuable identity product to achieve organisational success. The case studies also provide an analysis that contrasts aspects of the diffusion and promotion of collective identities through the use of the BSC. This demonstrates that clear direction in the identity management process is an important factor in the design and implementation of successful PMS programs. The value of this paper is to heighten recognition of the symbolic agency of PMS, as it serves as a subtle mechanism for identity management, and also to foster the collaboration of communication specialists and management accountants to achieve common organisational goals.
Resumo:
Identity is unique, multiple and dynamic. This paper explores common attributes of organisational identities, and examines the role of performance management systems (PMSs) on revealing identity attributes. One of the influential PMSs, the balanced scorecard, is used to illustrate the arguments. A case study of a public-sector organisation suggests that PMSs now place a value on the intangible aspects of organisational life as well as the financial, periodically revealing distinctiveness, relativity, visibility, fluidity and manageability of public-sector identities that sustain their viability. This paper contributes to a multi-disciplinary approach and its practical application, demonstrating an alternative pathway to identity-making using PMSs.
Resumo:
Is it possible to control identities using performance management systems (PMSs)? This paper explores the theoretical fusion of management accounting and identity studies, providing a synthesised view of control, PMSs and identification processes. It argues that the effective use of PMSs generates a range of obtrusive mechanistic and unobtrusive organic controls that mediate identification processes to achieve a high level of identity congruency between individuals and collectives—groups and organisations. This paper contends that mechanistic control of PMSs provides sensebreaking effects and also creates structural conditions for sensegiving in top-down identification processes. These processes encourage individuals to continue the bottom-up processes of sensemaking, enacting identity and constructing identity narratives. Over time, PMS activities and conversations periodically mediate several episode(s) of identification to connect past, current and future identities. To explore this relationship, the dual locus of control—collectives and individuals—is emphasised to explicate their interplay. This multidisciplinary approach contributes to explaining the multidirectional effects of PMSs in obtrusive as well as unobtrusive ways, in order to control the nature of collectives and individuals in organisations.
Resumo:
University libraries play an important role in contributing to student and faculty members’ academic achievement. This study examines perceptions of university library usage to consider factors that influence achievement of students, academics and administrators. A thorough review of relevant literature examined approaches to determining user satisfaction of students and faculty, and factors that influence library usage. It highlighted the value of usage on educational performance. It enabled development of a theoretical framework leading to the Factors of Academic Library Usage (FALU) model, which was developed to investigate the effect of usage factors. FALU was tested in Kuwait university libraries. The study used validated questionnaires from 792 students, 143 academics and 121 administrators to measure five library factors. Interviews were conducted across the three University libraries. The findings are useful in measuring the correlation between the current academic library usage and educational performance.