Design and fabrication of a nonlinear micro impact oscillator

In this paper we describe the design and fabrication of a mechanical autonomous impact oscillator with a MEMS resonator as the frequency control element. The design has been developed with scalability to large 2-D arrays of coupled oscillators in mind. The dynamic behaviour of the impact oscillator was numerically studied and it was found that the geometry nonlinearity has an effect on the static pull-in voltage and equilibrium position. The external driving power can alter the frequency of the impact oscillator. The autonomous nature of the oscillator simplifies the complexity of the drive circuitry and is essential for large 2-D arrays.

Template model for blur coding: the role of early nonlinearity in edge segmentation

We describe a template model for perception of edge blur and identify a crucial early nonlinearity in this process. The main principle is to spatially filter the edge image to produce a 'signature', and then find which of a set of templates best fits that signature. Psychophysical blur-matching data strongly support the use of a second-derivative signature, coupled to Gaussian first-derivative templates. The spatial scale of the best-fitting template signals the edge blur. This model predicts blur-matching data accurately for a wide variety of Gaussian and non-Gaussian edges, but it suffers a bias when edges of opposite sign come close together in sine-wave gratings and other periodic images. This anomaly suggests a second general principle: the region of an image that 'belongs' to a given edge should have a consistent sign or direction of luminance gradient. Segmentation of the gradient profile into regions of common sign is achieved by implementing the second-derivative 'signature' operator as two first-derivative operators separated by a half-wave rectifier. This multiscale system of nonlinear filters predicts perceived blur accurately for periodic and aperiodic waveforms. We also outline its extension to 2-D images and infer the 2-D shape of the receptive fields.

R&D, innovation and exporting:evidence from UK new technology based firms

We examine the relationship between R&D, innovation and exporting for a sample of new technology based firms (NTBFs) in the UK. Allowance is made for selection bias and for endogeneity between innovation and exporting. Innovators are more likely to export, but conditional on entering export markets successful innovation does not increases subsequent export intensity. Lagged productivity is strongly associated with exporting, supporting the view that efficient firms are better able to overcome the barriers to entering export markets. We also find strong evidence of the importance of internal R&D and of supply-chain collaborations in fostering innovation, and that formal commercial collaborations can be important in overcoming the (information) sunk costs of entering export markets. The use of e-commerce does nothing to boost entry into export markets, but the intensity of its use is associated with increased export intensity.

Three-dimensional modeling of the human eye based on magnetic resonance imaging

PURPOSE. A methodology for noninvasively characterizing the three-dimensional (3-D) shape of the complete human eye is not currently available for research into ocular diseases that have a structural substrate, such as myopia. A novel application of a magnetic resonance imaging (MRI) acquisition and analysis technique is presented that, for the first time, allows the 3-D shape of the eye to be investigated fully. METHODS. The technique involves the acquisition of a T2-weighted MRI, which is optimized to reveal the fluid-filled chambers of the eye. Automatic segmentation and meshing algorithms generate a 3-D surface model, which can be shaded with morphologic parameters such as distance from the posterior corneal pole and deviation from sphericity. Full details of the method are illustrated with data from 14 eyes of seven individuals. The spatial accuracy of the calculated models is demonstrated by comparing the MRI-derived axial lengths with values measured in the same eyes using interferometry. RESULTS. The color-coded eye models showed substantial variation in the absolute size of the 14 eyes. Variations in the sphericity of the eyes were also evident, with some appearing approximately spherical whereas others were clearly oblate and one was slightly prolate. Nasal-temporal asymmetries were noted in some subjects. CONCLUSIONS. The MRI acquisition and analysis technique allows a novel way of examining 3-D ocular shape. The ability to stratify and analyze eye shape, ocular volume, and sphericity will further extend the understanding of which specific biometric parameters predispose emmetropic children subsequently to develop myopia. Copyright © Association for Research in Vision and Ophthalmology.

Exploratory database visualisation: the application and assessment of data and dimensionality reduction

This thesis describes the development of a complete data visualisation system for large tabular databases, such as those commonly found in a business environment. A state-of-the-art 'cyberspace cell' data visualisation technique was investigated and a powerful visualisation system using it was implemented. Although allowing databases to be explored and conclusions drawn, it had several drawbacks, the majority of which were due to the three-dimensional nature of the visualisation. A novel two-dimensional generic visualisation system, known as MADEN, was then developed and implemented, based upon a 2-D matrix of 'density plots'. MADEN allows an entire high-dimensional database to be visualised in one window, while permitting close analysis in 'enlargement' windows. Selections of records can be made and examined, and dependencies between fields can be investigated in detail. MADEN was used as a tool for investigating and assessing many data processing algorithms, firstly data-reducing (clustering) methods, then dimensionality-reducing techniques. These included a new 'directed' form of principal components analysis, several novel applications of artificial neural networks, and discriminant analysis techniques which illustrated how groups within a database can be separated. To illustrate the power of the system, MADEN was used to explore customer databases from two financial institutions, resulting in a number of discoveries which would be of interest to a marketing manager. Finally, the database of results from the 1992 UK Research Assessment Exercise was analysed. Using MADEN allowed both universities and disciplines to be graphically compared, and supplied some startling revelations, including empirical evidence of the 'Oxbridge factor'.

Enhancing delivery of health behaviour change interventions in primary care: a meta-synthesis of views and experiences of primary care nurses

Objective To systematically find and synthesise qualitative studies that elicited views and experiences of nurses involved in the delivery of health behaviour change (HBC) interventions in primary care, with a focus on how this can inform enhanced delivery and adherence to a structured approach for HBC interventions. Methods Systematic search of five electronic databases and additional strategies to maximise identification of studies, appraisal of studies and use of meta-synthesis to develop an inductive and interpretative form of knowledge synthesis. Results Nine studies met the inclusion criteria. Synthesis resulted in the development of four inter-linking themes; (a) actively engaging nurses in the process of delivering HBC interventions, (b) clarifying roles and responsibilities of those involved, (c) engaging practice colleagues, (d) communication of aims and potential outcomes of the intervention. Conclusion The synthesis of qualitative evidence resulted in the development of a conceptual framework that remained true to the findings of primary studies. This framework describes factors that should be actively promoted to enhance delivery of and adherence to HBC interventions by nurses working in primary care. Practice implications The findings can be used to inform strategies for researchers, policymakers and healthcare providers to enhance fidelity and support delivery of HBC interventions.

Studies on the chromosomal bets-lactamase of pseudomonas aeruginosa

The chromosomal ß-lactamase of Pseudomonas aeruginosa SAlconst (a derepressed laboratory strain) was isolated and purified. Two peaks of activity were observed on gel permeation chromatography (one major peak mol. wt. 45 kD and one minor peak of 54 kD). Preparations from 12 clinical derepressed strains showed identical results. Chromosomal ß-lactamase production in both normal and derepressed P. aeruginosa strains was induced both by iron restricted growth conditions and by penicillin G. The majority of the enzyme (80-90%) was found in the periplasm and cytoplasm but a significant amount (2-20%) was associated with the outer membrane (OM). The growth conditions did not affect the distribution of the enzyme between subcellular fractions although higher activity was found in the cells grown under iron limitation and/ or in the presence of ß-lactams. The penicillanate sulphone inhibitor, tazobactam, displayed irreversible kinetics whilst cloxacillin, cefotaxime, ampicillin and penicillin G were all competitive inhibitors of the enzyme. Similar results were obtained for the Enterobacter cloacae P99 [ß-lactamase, but tazobactam displayed a non-classical kinetic pattern for the Staphylococcus aureus PC1 ß-lactamase. The residues involved in ß-lactam hydrolysis by the P aeruginosa SAlconst enzyme were detennined by affinity labelling with tazobactam. A tryptic digestion fragment of the inhibited enzyme contained the amino acids D, T, S, E, P, G, A, C, V, M, I, Y, F, H, K, R. This suggests the involvement of the conserved SVSK, DAE and KTG motifs found in all penicillin sensitive proteins. A model of the 3-D structure of the active site of the P aeruginosa SAlconst chromosomal ß-!actamase was constructed from the published amino acid sequence of P aeruginosa chromosomal ß-lactamase and the a-carbon coordinates of the S. aureus PCI ß-lactamase by homology modelling and energy minimisation. The crystal structure of tazobactam was determined and energy minimised. Computer graphics docking identified Ser 72 as a possible residue involved in a secondary attack on the C5 position of tazobactam after initial ß-lactam hydrolysis by serine 70. The enhanced activity of tazobactam over sulbactam might be explained by the triazole substituent which might participate in favourable hydrogen bonding between N3 and active site residues.

Indigenous and foreign innovation efforts and drivers of technological upgrading:evidence from China

This paper explores the role of indigenous and foreign innovation efforts in technological upgrading in developing countries, taking into account sectoral specificities in technical change. Using a Chinese firm-level panel dataset covering 2001–05, the paper decomposes productivity growth into technical change and efficiency improvement and examines the impact of indigenous and foreign innovation efforts on these changes. Indigenous firms are found to be the leading force on the technological frontier in the low- and medium-technology industries, while foreign-invested firms enjoy a clear lead in the high-technology sector. Collective indigenous R&D activities at the industry level are found to be the major driver of technology upgrading of indigenous firms that push out the technology frontier. While foreign investment appears to contribute to static industry capabilities, R&D activities of foreign-invested firms have exerted a significant negative effect on the technical change of local firms over the sample period.

R&D, product innovation, and exporting:evidence from UK new technology based firms

We examine the relationship between R&D, product innovation, and exporting for a sample of new technology based firms (NTBFs) in the UK. Allowance is made for selection bias and for endogeneity between innovation and exporting. Product innovators are more likely to export, but conditional on entering export markets successful innovation does not increase subsequent export intensity. Lagged productivity is strongly associated with exporting, supporting the view that efficient firms are better able to overcome the barriers to entering export markets. We also find strong evidence of the importance of internal R&D and of supply-chain collaborations in fostering innovation, and that formal commercial collaborations can be important in overcoming the (information) sunk costs of entering export markets. The use of e-commerce does nothing to boost entry into export markets, but the intensity of its use is associated with increased export intensity.

Functional Transfer Theorems for Maxima of Stationary Processes

2000 Mathematics Subject Classification: 60G70, 60F12, 60G10.

Study on Robustness of Strehler-Mildvan Model

2000 Mathematics Subject Classi cation: 62F35, 62F15

To what extent and in what manner do Chinese and Indian contract research organisation learn and upgrade with the unbundling the global pharmaceutical R&D value chain?

The paper applies the GVC framework to analyse the organisational and geographical reconfiguration of the global R&D function of leading US and European pharmaceutical MNCs. Though pharmaceutical MNCs have been outsourcing clinical trial activities since the mid-1990s, the outsourcing of discovery research tasks is a phenomenon of the 2000s (Ramirez 2013). Moreover, in the context of a crisis of R&D productivity and increasing pressure from shareholders, a number of US and European pharmaceutical MNCs are breaking up their R&D function in an attempt to increase flexibility and reduce risk as well as costs and are thereby restructuring the global architecture of their R&D function. This break-up, or unbundling (Sako 2006), of the R&D function is particularly interesting given the prevalence of market failure in innovation (Howells et al 2008), the non-modular nature of the R&D process in this industry (Pisano 2006) and the strategic important of this activity to the core competence and long-term competitive advantage of firms in this sector. The focus of this paper is on the outsourcing of R&D activities to Chinese and Indian independently-owned contract research organisations (CROs) and the way these firms are becoming integrated as service providers into the global R&D function (or R&D value chain) of pharmaceutical MNCs. Above all the paper is concerned with the development of capabilities of CROs from these two countries and the dynamics of upgrading in GVCs in knowledge-intensive functions. The paper therefore discusses the role of both knowledge flows within global pharmaceutical R&D value chains as well as national innovation systems on the development of capabilities of Chinese and Indian CROs. Our analysis is based on data from semi-structured interviews collected from senior R&D managers from a sample of ten US and European pharmaceutical MNCs and owners and senior R&D managers from five Chinese and five Indian CROs who are providing research services to MNCs in this industry. We discuss the emergence of R&D outsourcing in this industry and the nature and mechanisms of knowledge flows within R&D value chains. The embeddedness of CROS in the national innovation systems of their home countries is also discussed.

Adolescent readers' self-perceptions of affective factors related to performance on standardized tests

The purpose of this study was to investigate which affective factors of adolescent high school readers were related to high-level readers, middle-level readers and low-level readers. The research problem was to determine the relationship between adolescent high school students' self-perceived reading self-efficacy factors and the students' reading performance on a standardized reading assessment considering demographic factors of age, gender and socio-economic status as covariates. The research design was ex post facto making inferences without direct intervention. The sample was obtained from one large, diverse, urban high school, consisting of 9th and 10th grade adolescent students (N = 176). Students voluntarily completed a self-report, reading self-efficacy survey. School records were used to obtain standardized reading level scores, age, gender, and socio-economic status data. An exploratory factor analysis of the self-efficacy survey responses resulted in the identification of 7 underlying factors. The striving (low-level) readers had significantly lower self-perceptions on 5 of the 7 affective factors than the middle-level readers, and strong (high-level) readers, p < .05. The 5 affective factors on which the striving readers had significantly lower self-perceptions were: (a) Observational Comparison, (b) Progress, (c) Lack of Progress, (d) Lack of Anxiety, and (e) Positive Social Feedback. The 2 affective factors which were not significantly different for reader level were Anxiety and Negative Social Feedback. Girls had significantly less anxiety than boys for both of the factors in the Anxiety category. Statistical results showed that none of the demographic covariates tested; age, gender, or socio-economic status, moderated the relationship between affective reader self-efficacy factors and reader level. This study concluded that there were distinguishable differences for striving, middle, and strong readers' self-efficacy factors. Determining affective factors related to reading can be used to create better instructional environments and instruction for adolescent students.

Origin of salinity variations in Florida Bay

This note presents a method of distinguishing the source of freshwater that causes reductions in salinity in the coastal environment of South Florida. This technique, which uses the 18O and D of the water, allows for differentiation of the freshwater derived from precipitation as opposed to runoff, because surface waters in the Everglades have been highly evaporated and therefore have elevated 18O and dD values relative to precipitation. A time series of monthly 18O and D values of surface waters, collected from stations in Florida Bay between 1993 and 1999, has shown that, during this time, the major source of freshwaters causing depressions in the salinity in the western portion of Florida Bay was derived from precipitation rather than from the runoff of water from the Everglades. In the eastern portion of Florida Bay, close to the boundary between peninsular Florida and the Bay, the proportion of freshwater derived from precipitation drops steadily, reaching <10%. This method not only allows differentiation between the sources of freshwater but can, in a temporal sense, ascertain the effectiveness of water management practices on the salinity of the estuarine ecosystems of South Florida.

The Study of Sonar for Imaging of the Solid-Liquid Interface Inside Large Tanks

Retrieval, treatment, and disposal of high-level radioactive waste (HLW) is expected to cost between 100 and 300 billion dollars. The risk to workers, public health, and the environment are also a major area of concern for HLW. Visualization of the interface between settled solids and the optically opaque liquid is needed for retrieval of the waste from underground storage tanks. A Profiling sonar selected for this research generates 2-D image of the interface. Multiple experiments were performed to demonstrate the effectiveness of sonar in real-time monitoring the interface inside HLW tanks. First set of experiments demonstrated that objects shapes could be identified even when 30% of solids entrained in liquid, thereby mapping the interface. Simulation of sonar system validated these results. Second set of experiments confirmed the sonar’s ability in detecting the solids with density similar to the immersed liquid. Third set of experiments determined the affects of near by objects on image resolution. Final set of experiments proved the functional and chemical capabilities of sonar in caustic solution.