152653 research outputs found
Sort by
Studying cardiac contractility change trend to evaluate cardiac reserve
No full textThere is a very close relationship between the amplitude of the first heart sound and the cardiac contractility. We previously presented the concept of cardiac contractility variability (CCV) and an analysis method. On the basis of the findings from the authors' observation and other previous studies, a conclusion can be made that the variability of the first heart sound amplitude is a reflection of CCV. We found that an increase of the amplitude of the first heart sound can be seen on the phonocardiogram obtained even after a small workload exercise. We defined the increase of the amplitude of the first heart sound after accomplishing different exercise workloads, with respect to the amplitude of the first heart sound recorded at rest as cardiac contractility change trend (CCCT). CCCT implies information about cardiac contractility and cardiac reserve. To explore the significance of CCCT for evaluating cardiac contractility reserve of a patient or an athlete, we carried out a study on cardiac contractility change trend, the methods and the results of which are presented
Micromachined diaphragm transducers for miniaturised ultrasound arrays
Full text linkMiniaturised ultrasound transducer arrays with integrated electronics will in future enable significant advances in high resolution medical imaging and in acoustic tweezing for bioscience research. However, their development has been limited by challenges in scaling down conventional piezoelectric ultrasound transducer fabrication and interconnection techniques. Piezoelectric thin film transducers on silicon substrates can overcome these challenges by reducing dimensional constraints in fabrication and facilitating integration with electronics, including allowing low drive voltages in transmission. We present the design, fabrication and testing of diaphragm transducers to evaluate the feasibility of integrated piezoelectric micromachined ultrasonic transducers (PMUTs). Transducers have been designed, then fabricated with 80 µm and 130 µm diameter diaphragms, the latter in arrays with ~500 diaphragms. Receive measurements demonstrate functionality of both devices, with pulse-echo bandwidths of approximately 90% for the 80 ?m diaphragms, demonstrating initial feasibility for ultrasound imaging
The moral foundations of constitutional change in Canada and Scotland at the end of the twentieth century
No full textEquivalent-linear stiffness and damping in rocking of circular and strip foundations
No full textAn approximation is developed for obtaining the nonlinear stiffness KR and damping CR of a shallow circular or strip footing undergoing rocking oscillation on a homogeneous but inelastic undrained clayey stratum. Based on the parametric results of 3-D and 2-D finite-element analyses, equivalent-linear KR and CR are expressed in readily usable dimensionless forms. KR, normalized by its linear elastic value, is shown to be a unique function of: (1) the vertical factor of safety Fs against static bearing capacity failure, and (2) the angle of rotation θ{symbol} normalized by a characteristic angle θ{symbol}s. The latter is approximately the angle for which uplifting usually initiates at one edge of the foundation. Three sources contribute to the value of the dimensionless damping ratio ξR (derived from CR): wave radiation, which is a function of frequency but is shown to amount to <3 %; soil inelasticity (hysteresis), for which graphs are developed in terms of θ{symbol}/θ{symbol}s and Fs; and energy loss due to impact and the collateral vertical motion when severe uplifting takes place, which is tentatively determined from dynamic M: θ{symbol} loops. Comparative parametric seismic time-history analyses provide an adequate validation of the iterative equivalent-linear approximation which implements the developed equivalent KR and ξR, but they also highlight its limitations.</p
Acceptability of the Hall Technique in New Zealand
No full textObjective: To investigate the acceptability of stainless steel crowns placed by dental therapists on children’s primary molars using the Hall Technique.Design: Mixed methods approach, using qualitative inductive analysis and quantitative analysis.Setting: Hawke’s Bay Community Oral Health Service Methods: One focus group was conducted and ten thirty-minute phone interviews were undertaken with parents of children who had previously had a stainless steel crown placed using the Hall Technique (over the period 1 December 2011 to 31 May 2012). An inductive approach was used to analyse the qualitative research data, and the information was arranged into several categories based on the key themes which arose. Children treated with the Hall Technique were asked immediately after treatment whether they had enjoyedtheir visit to the clinic that day.Results: Common themes were found with regard to appearance, pain, the procedure, and general opinions on acceptability. Nearly all (90%) of the childrenresponded positively about their visit to the clinic.Conclusion: There was a high degree of acceptance among both parents and children for stainless steel crown placement using the Hall Technique in this group
From resilience to resistance:Political ecological lessons from antibiotic and pesticide resistance
No full textThis article investigates the interplay of natural and human systems with reference to the growing global problem of antibiotic resistance. Among the diverse causes of antibiotic resistance, we focus broadly on three related causes: pharmaceutical practice and the liberal consumption of antibiotics, the use of antibiotic-containing products in the home, and the use of antibiotics in commercial animal husbandry and agriculture. We draw a parallel between pesticide and antibiotic resistance and ex- amine whether lessons learned from one case may be applicable to the other. Although our main focus is a micro-ecological analysis examining how humans are changing their environments, our conclusion addresses larger implications of this problem for global health. Through the theoretical lens of political ecology, we ask how we may address the “tragedy of the antibiotic commons” through public education and consumer activism as well as global health governance
Proposed environmental enforcement framework
No full textBrief note on Scottish Government consultation on enforcement of environmental la
Printmaking in the post-print age:critical and creative methods in the context of contemporary art and society
No full textThe collaborative processes between artist/ printmaker and scientists is the subject of my proposed paper and the topic for discussion for the Impact 9 Conference in Hangzhou 2015. In 2006, I undertook a collaborative art-science research project with scientists from the Scottish Crop Research Institute (now the James Hutton Institute), entitled Blueprint for Bacterial Life. Using advanced digital tools I developed the concept of their Genome Diagram into a multimedia interactive installation with animations and music based on the genetic plasticity and evolution of bacterial pathogens. I began by creating a series of etchings and screen-prints using a very subtle range of silvery blues and greys and worked with some specific inks known as interference inks. It was through looking at those prints that the scientists noticed the occurrence of new elements and a very specific event of gene acquisition. By simplifying the diagram into a tonal variation and re-contextualizing the data it revealed information that the scientists had completely overlooked. Their scientific approach to the data was systematic and empirical. By chance, this artistic re-interpretation of the scientific data contributed to a new insight. Rather than simply identifying genes unique to a pathogen, the screen-prints revealed the presence of other genes in all of the bacteria, possibly representing genes essential to all forms of bacteria
Peer tutoring in reading:the effects of role and organization on two dimensions of self-esteem
No full textBackground. Paired reading (PR) is an application of peer tutoring. It has been extensively researched, and its efficacy across a range of outcomes has been established. Benefits include improvements in key reading skills, and also in affective aspects of learning. Several studies have shown gains in self-esteem, although measurement methods have varied, and the model of self-esteem has rarely been clearly articulated.Aims. To investigate the changes in self-esteem of children participating in a randomized trial of PR over a 15-week treatment period. To investigate the relative contribution of self-worth and self-competence to any gains in self-esteem. To investigate whether the pattern of change differs in children who take on different roles in the PR process.Participants. The participants comprised a subset of a large-scale randomized trial of peer learning (The Fife Peer Learning Project). Four schools were randomly selected from schools allocated to the same-age PR condition, and four schools from those allocated to the cross-age PR condition. The same-age group consisted of 87 primary 6 children (10-11 years old). The cross-age group consisted of 81 primary 6 children. The controls, from schools randomly selected from a neighbouring authority, consisted of 92 primary 6 children.Method. A pre-post design employing self-report measures of self-esteem. Rosenberg's Self-Esteem Scale was used, with scores analysed for worth and competence. The treatment period was 15 weeks, with the participants following a prescribed PR process.Results. Significant pre-post gains were noted in self-esteem, driven predominantly by improved beliefs about competence, in both same-age and cross-age conditions, but not for controls. Gains were also seen in self-worth in the cross-age condition. Further analyses of the influence of organizational condition (same-age or cross-age) and role played (tutor vs. tutee) showed significant differences between same-age tutors and cross-age tutors in relation to self-worth. Effect sizes were generally small or moderate.Conclusions. The findings provide further support for the belief that PR can enhance self-esteem. Importantly, the use of a two-dimensional model provides extra information about self-perceptions in PR contexts: first, the central role of self-competence; and second, the gains in self-worth which are associated with tutoring younger children (but not same-age peers). This new information has educational significance for schools considering the potential of peer tutoring and the benefits of different organizational conditions.</p
Centrifuge modelling of hillslope debris flow initiation
No full textPhysical modelling of hillslope debris flow initiation was undertaken using the geotechnical beam centrifuge at the University of Dundee. The tests were carried out on model slopes consisting of soils with known properties prepared with constant initial density and material thickness. The results showed that soils with a higher silt fraction can sustain a higher increase in pore water pressure and thus a greater reduction in effective stress before failure is induced. This suggests that sand rich soils with lower fines content are geotechnically more susceptible to slope failure and that observed higher spatial frequencies of debris flow on slopes with coarse grained bedrocks can be partially explained in terms of lower critical pore pressure failure thresholds amongst the sandier soil matrixes produced from such lithologies. Differences in rates of water ingress into the model soils required to trigger a critical rise in pore pressures during the tests provide insights into the varying synoptic conditions and antecedent rainfall characteristics that are likely to trigger debris flows in different soil types
Data sources:
Access Repository Dashboard
Do you manage University of Dundee Online Publications? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!