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Validation of the comprehensive inventory of mindfulness experiences (CHIME) in English using Rasch methodology
No full textAlthough mindfulness has been studied for multiple decades, psychometric research has yet to agree upon the optimal way to measure the mindfulness construct. Prior research has identified eight distinct aspects of mindfulness that were not adequately captured by any of the available measures. Hence, the Comprehensive Inventory of Mindfulness Experiences (CHIME) was developed. The CHIME contains 37 items and was originally developed in the German language. The CHIME has demonstrated excellent psychometric properties in both German and Dutch, but so far, no English version has been validated. The purpose of the present study was to investigate the psychometric characteristics of the translated English-language CHIME scale using Rasch methodology.
Method: The current study utilized Partial Credit Rasch analysis to evaluate the psychometric characteristics of the English CHIME. The sample included responses from 620 participants from the general population residing in the USA. The validity of the English CHIME was examined by correlating its scores with various measures of mindfulness and psychological functioning.
Results: Initial Rasch analysis of the English CHIME showed poor model fit, local dependency, and evidence against the assumption of unidimensionality. Several minor modifications, that involved creating super-items, were required to fit the Rasch model χ2(45)=31.99, p=0.93). This model displayed evidence of unidimensionality, invariance across personal factors, and a high reliability (PSI=0.92). Ordinal-interval transformation tables were produced, which increase the English CHIME’s precision of measurement. The English CHIME’s external validity was established by moderate–high correlations with other measures of mindfulness and various measures of psychological functioning.
Conclusions: The results of this study provide evidence for the validity of the English CHIME scale, which can be used to assess the overarching construct of mindfulnes
Spatial variation of the non-linear interactions between estuarine flooding drivers in Aotearoa New Zealand
No full textCoastal flooding is one of the main concerns worldwide associated with climate change.
Historically, coastal cities have regularly experienced hazardous flooding across the globe,
contributing to coastal population vulnerability. In Aotearoa New Zealand, an island nation,
the outlook of rising sea levels is especially concerning due to the number of people that live
in the coastal zone. Predicting extreme water levels is challenging and depends on properly
identifying the main physical processes. Swells, wind waves, storm surges, and astronomical
tides are transformed when propagating inside shallow coastal lagoons, bays and estuaries,
mainly because of their mutual interaction (e.g., phase alteration) but also because of the effects
of constrictions and friction imposed by the estuarine morphology (e.g., amplification and
asymmetry). Furthermore, the compound action of different drivers and extreme events in close
succession can exacerbate flooding. The understanding of non-linear interactions between
flooding drivers can substantially improve the power of prediction of flooding in coastal areas
with complex morphology such as estuaries. For that, proper bathymetry and topography data
are fundamental for assessing flooding risk, which can be challenging because some of the
current acquision methods are economically expensive or not applicable to remote and shallow
areas exposed during low tide. Satellite-derived bathymetry and topography are a recent
approach which are increasingly used to tackle this issue.
Although flooding drivers have already been identified and studied around the coast of
Aotearoa New Zealand, few studies have focused on their interaction inside estuaries. Similarly,
very little has been undertaken on the applicability of satellite-derived elevation data for
hydrodynamic modelling. This thesis regionally assesses the non-linear interactions between
storm surges, waves, astronomical tides and estuarine morphology and the suitability of
satellite-derived data to represent these complex interactions in hydrodynamic models.
The main findings are that tide-surge interactions are a major contributor to the water level
inside estuaries and cannot be neglected when simulating flooding events. Tide-surge
interactions can represent variations in the water level ranging from -16 cm (below mean sea
level) to +27 cm (above mean sea level). In addition, non-linear interactions induced by the
estuarine morphology — especially the coverage of the intertidal zone related to the total
surface area of the estuary — modulate the co-occurrence rate between events outside and
inside an estuary. It was found that co-occurrence rates can vary largely according to the estuary
(20–86%). Furthermore, storm-surge and wave interactions have shown strong potential for
compound and clustering effects in estuaries on the North Island, linked to severe south and
southwesterly winds generated by local weather patterns. Wave height and storm surges
corresponding to extreme water levels are significantly correlated, especially inside estuaries
in locations close to the estuarine entrance. Wind waves are more strongly correlated to storm
surges on the west coast while swell waves show a stronger correlation on the east coast of the
North Island. However, when wind and swell waves are combined (i.e., integrated wave
hindcast data) the correlation between wave heights and storm surges is stronger than when
analysed separately. Furthermore, independent and clustered extreme events of waves and
storm surges follow similar seasonality, can co-occur and can be composed of up to 12 extreme
events occurring within 15 days. Finally, based on existing techniques, a framework was
applied to obtain satellite-derived topo-bathymetric data. Although the applied method is
sensitive to several factors (e.g., the complexity of the relief, number of processed images,
bottom reflection), the derived topographic data showed good approximation to LiDAR data
validation — showing similar accuracy of ~20 cm, in an elevation range of approximately 2m.
The elevation estimates were used in hydrodynamic modelling to assess extreme water levels
in a complex estuarine system, considering non-linear interactions. Simulation scenarios using
only satellite-derived elevations could represent extreme water levels inside an estuary with
complex morphology with comparable accuracy of the scenarios using topo-bathymetric data
acquired using in-situ methods (< 0.1 m difference). The results show that satellite-derived data
can be a good replacement when data originating from traditional methods are scarce or
unavailable.
In conclusion, the thesis shows the regional patterns of non-linear interactions between
different flooding drivers around Aotearoa New Zealand, showing where and when these
interactions are important. Furthermore, it shows how satellite-derived techniques can improve
the power of predicting flooding in remote areas with data scarcity. These findings are crucial
for enhancing the prediction of flooding in morphologically complex areas such as estuaries,
where a great part of the coastal community and civil infrastructure are based and have major
social-economic importance. A better understanding of estuarine flooding would make coastal
adaptation policies more effective by making the current models more accurate
Meta-analysis comparing the efficacy of ACT and CBT for academic procrastination
No full textThe efficacy of acceptance and commitment therapy (ACT) and cognitive behavioural therapy (CBT) was meta-analytically examined to identify if they are effective interventions for reducing the academic procrastination of students. A comparison of the efficacies of ACT and CBT as the more effective treatment in reducing academic procrastination in students at post-treatment and follow-up was also assessed. I conducted a meta-analysis of nine randomised-control trials. A large overall pooled effect size of g = -1.96, 95% CI [-4.48, 0.57] was found in favour of ACT and CBT treatment interventions compared to control in reducing academic procrastination. CBT was more effective at reducing academic procrastination post-treatment with a moderate effect size, g = -0.69, 95% CI [-1.14, 0.24] compared to ACT, with a small effect size, g = -0.33, 95% CI [-1.38, 0.72]. This is one of the first meta-analyses to directly compare ACT and CBT interventions in relation to the academic procrastination of students. Limitations and future recommendations are discussed
An expert-driven framework for applying eDNA tools to improve biosecurity in the Antarctic
No full textSignatories to the Antarctic Treaty System’s Environmental Protocol are committed to preventing incursions of non-native species into Antarctica, but systematic surveillance is rare. Environmental DNA (eDNA) methods provide new opportunities for enhancing detection of non-native species and biosecurity monitoring. To be effective for Antarctic biosecurity, eDNA tests must have appropriate sensitivity and specificity to distinguish non-native from native Antarctic species, and be fit-for-purpose. This requires knowledge of the priority risk species or taxonomic groups for which eDNA surveillance will be informative, validated eDNA assays for those species or groups, and reference DNA sequences for both target non-native and related native Antarctic species. Here, we used an expert elicitation process and decision-by-consensus approach to identify and assess priority biosecurity risks for the Australian Antarctic Program (AAP) in East Antarctica, including identifying high priority non-native species and their potential transport pathways. We determined that the priority targets for biosecurity monitoring were not individual species, but rather broader taxonomic groups such as mussels (Mytilus species), tunicates (Ascidiacea), springtails (Collembola), and grasses (Poaceae). These groups each include multiple species with high risks of introduction to and/or establishment in Antarctica. The most appropriate eDNA methods for the AAP must be capable of detecting a range of species within these high-risk groups (e.g., eDNA metabarcoding). We conclude that the most beneficial Antarctic eDNA biosecurity applications include surveillance of marine species in nearshore environments, terrestrial invertebrates, and biofouling species on vessels visiting Antarctica. An urgent need exists to identify suitable genetic markers for detecting priority species groups, establish baseline terrestrial and marine biodiversity for Antarctic stations, and develop eDNA sampling methods for detecting biofouling organisms
Power conditioning and power protection for electronic systems
No full textElectrical energy is the most convenient form of energy, and modern society takes it for granted that it is always available by our side. We have a legacy AC power grid where systems were historically developed based on the assumption that electricity is generated in bulk at far-away sites from our cities and neighbourhoods. Nationwide AC transmission and distribution networks use the advantages of line frequency transformers for voltage conversions with ‘adequate’ efficiency.
Given the distributed nature of these AC power networks, with many long-distance high-voltage transmission lines and electrical substations distributed over wider geographical regions, they are naturally exposed to acts of God, such as extreme weather events and lightning strikes. Furthermore, with the increasing complexity of the power networks, complex control systems are utilized at network substations, which could occasionally have accidental failures due to system reliability issues or human errors. The overall effect is that these unexpected random events could create power quality issues and systemic issues such as overloading and sudden load shedding
Privacy regulation of cellular network data: A comparative study with recommendations for the Kingdom of Saudi Arabia
No full textOne of the primary economic objectives of multinational technology corporations is to amass a significant amount of personal data, potentially leading to significant infringements of individuals' privacy rights. The advent of the technology revolution has resulted in a swift evolution of privacy laws in numerous jurisdictions. This can be attributed to the enhanced capacity of governmental and commercial entities to monitor and accumulate extensive data, as well as the economic objectives of global technology corporations to amass copious amounts of personal information. The Kingdom of Saudi Arabia has yet to implement legal provisions that ensure the privacy rights of its citizens and has also not introduced any legislation that safeguards the confidentiality rights of its citizens. The Kingdom of Saudi Arabia is currently contemplating the possibility of implementing a privacy legislation that considers not only its own distinct national culture, but also the role of privacy within the cultures of the surrounding region, as well as on a global scale. Annually, a vast number of international tourists travel to the Kingdom of Saudi Arabia, which has established a comprehensive plan and outlook aimed at luring multinational corporations across diverse sectors. Due to the aforementioned circumstances, it is imperative for the Kingdom of Saudi Arabia to establish a robust legislative framework that can effectively protect personal data. It is noteworthy that the Kingdom of Saudi Arabia operates under the governance of Sharia Law and Islamic Jurisprudence, which serve to safeguard the entitlement to confidentiality and privacy of personal data. The preservation of privacy and confidentiality of personal information is a significant concern for the inhabitants of the Kingdom of Saudi Arabia, and they handle these issues with great sensitivity. In contemporary times, characterised by technological advancements and rapid global and economic development, it is imperative to institute legislation that protects the data and information infrastructure of the Kingdom of Saudi Arabia, in addition to the personal privacy of its populace. The thesis delves into the significance of privacy and examines the measures taken by various jurisdictions to safeguard the personal information of their residents. Additionally, it explores the potential lessons that the Kingdom of Saudi Arabia can draw from these examples
The development of an international model for technology adoption: the case of Hong Kong
Get PDFThe purpose of this study is to examine the causal relationships between the internal beliefs formation of a decision-maker on technology adoption and the extent of the development of a technology adoptive behaviour. In particular, this study aims to develop an International Model For Technology Adoption (IMTA), which builds upon the Theory of Planned Behaviour (Ajzen 1992) and improves on the framework of the Technology Acceptance Model (Davis 1986).
The development of such a model requires an understanding of the environmental factors which shape the cognitive processes of the decision maker. Hence, this is a behavioural model which investigates the constructs influencing the adoption behaviour and how the interaction between these constructs and the external variables can impact on the decision making process at the level of the firm.
Previous research on technology transfer and innovation diffusion has classified factors affecting the diffusion process into two dimensions: 1) external-influence and 2) internal-influence. Hence, in this research, the International Model For Technology Adoption looks at how the endogenous and exogenous factors enter into the cognitive process of a technology adoption decision through which attitudes and behavioural intentions are shaped.
Under the IMTA, the behavioural intention to adopt is a function of two exogenous variables, 1) Strategic Choice, and 2) Environmental Control. The Environmental Control factor is further categorised by two exogenous factors, namely, 1) Government Influence, and 2) Competitive Influence. In addition, the Competitive Influence factor is, in turn, classified into five forces: namely, 1) Industry Structure, 2) Price Intensity, 3) Demand Uncertainty, 4) Information Exposure, 5) Domestic Availability.
Regarding the cognitive process which forms the attitude to adopt, it is hypothesised to be affected by six other endogenous beliefs: 1) Compatibility; 2) Enhanced Value; 3) Perceived Benefits; 4)Adaptative Experiences, 5) Perceived Difficulty; and 6) Suppliers’ Commitment.
A survey research method was utilised in this study and the research instrument was developed after a comprehensive review of the relevant literature and an expert interview. A total of 298 completed questionnaires were returned; giving a response rate of 13.56%. Of the 298 questionnaires, 39 of the responses were unusable with missing date. This gives a total of 259 usable questionnaires and an effective response rate of 11.78%.
The results of the analysis suggested that the fitness of the International Model For Technology Adoption was good and the data of this study supported the overall structure of the IMTA. When compared with the null model, which was used by the EQS as a baseline model to judge to overall fitness for the IMTA, the IMTA yielded a value of 0.914 in the Comparative Fit index; hence, indication of a good fit model.
In addition, the results of the principal component analysis also illustrated that the 16-factor International Model For Technology Adoption was an adequate model to capture the information collected during the survey. The results shown that this 16-factor structure represented nearly 77% of the total variance of all items. A further analysis into the factor structure, again, revealed that there existed a perfect match between the conceptual dimensionality of the International Model For Technology Adoption and the empirical data collected in the survey.
However, the results of the hypotheses testing on the individual constructs were mixed. While not all the magnitude of these ten hypotheses was statistically significant, almost all pointed to the direction conceptualised by the IMTA.
From these results, it can be interpreted that while the results of the structural equation modelling analysis provided overall support to the International Model For Technology Adoption, the results of individual constructs of the Model revealed that some constructs were forming a larger impact than others in the decision making process to adopt foreign technology. In particular, the intention to adopt was greatly affected by the attitude of the prospective adopters, the influence of the government and the degree of industry rivalry. However, the impact of the overall competitive influence factor on the intention to adopt was not supported by the results. Again, the existence of investment alternative was also not a serious concern for the prospective adopters
Eye tracking in children with ADHD: exploring new diagnostic measures and reading training procedures
Get PDFThe overall aim of this research was to explore new diagnostic measures and reading training procedures for children with Attention Deficit Hyperactivity Disorder (ADHD). Specifically, it was hypothesised that the participants with ADHD would have different eye movement behaviours when reading aloud and silently compared to matched controls. It was also hypothesised that there would be a relationship between their eye movement behaviours and their leg and arm movements, with the administration of methylphenidate producing noticeable changes. The participants consisted of three male children with ADHD, aged between 7-8 years, and two reading level and age matched controls. The research consisted of two experiments during which the participants read short stories, while ignoring two visual distracters. The eye tracker recorded their eye lines of gaze, including their the number of fixations and the angles of saccades. During the training procedure, visual reminders prompted the participants to focus their attention on the reading task. As additional help, the computer-generated words were highlighted on the desired reading position. A calibration procedure that accommodated the hyperactivity of the participants with ADHD was successfully designed and outlined. Preliminary results indicate that the eye movements of the participants with ADHD differed from that of their matched controls and were characterised by rapidly changing lines of gaze and shorter fixation periods, which tended to be more pronounced when reading silently. :MPH reduced the amount of arm and leg movements but did not reduce the rapidly changing eye movements of one participant with ADHD, compared to matched controls with and without ADHD. The visual prompts in the training procedure had little social validity, but highlighting the text resulted in an increased consistency in the eye movement variables and reading performance when reading aloud and silently for both the participants with and without ADHD
A new optical configuration for flow cytometric sorting of bovine spermatozoa by sex
Get PDFThe orthogonal axes of illumination, flow, and detection in conventional sorting flow cytometers can limit accuracy or throughput when making fluorescence measurements on aspherical cells. We report a new radially symmetric optical configuration that has been designed to overcome these problems. This system has specifically been developed for high resolution DNA chromosome content measurement in cells with an ultimate goal to separate X- and Y-chromosome-bearing mammalian spermatozoa.
The new optics design provides radially symmetric illumination and detection of asymmetric particles while retaining the sort capability of a jet-in-air (or cylindrical cuvette) design. A paraboloidal reflector, symmetrical about the sample stream flow axis, both focuses a laser excitation beam and collects cell scatter and fluorescence from the inspection point.
The performance of the new optical configuration has been tested and compared to that of a conventional (orthogonal optical geometry) flow cytometer for a variety of particles and cells. For fluorescence measurements on calibration microspheres the new system produces histograms with similar coefficients of variation to those obtained with the conventional cytometer. Optical artifacts apparent in measurements on flat cells, such as blood cells and mammalian sperm, using conventional optics are overcome by the new configuration. Analysis of chinchilla sperm yields a dual-peaked histogram population that has a coefficient of variation and X-Y split which matches that for a gated (oriented) fraction of the sample as measured by the orthogonal system. Bovine sperm, which are larger and flatter than chinchilla sperm, also produce a single population which, when low sample to sheath differential pressures are used, has coefficients of variation matching those for an oriented subpopulation as measured by conventional optics.
Further modifications to the radial optics system have been carried out to study the effect of cell orientation (with respect to the excitation source) on fluorescence. A ray tracing model has been developed to explain the optical artifacts associated with the measurement of aspherical cells in orthogonal flow systems. This model has been used to verify the experimental findings from our cell orientation studies.
The radially symmetric optics we have described can be used to overcome the optical artifacts which decrease the accuracy of optical measurements on aspherical cells. With an added electrostatic sort capability, this system provides the high speed sort rates of conventional jet in air flow cytometers. The system presents an alternative, orientation-independent technique for measuring aspherical cells independent of their orientation. This optical configuration may provide a means for increasing throughput and accuracy for sperm sexing and other applications which require high resolution measurement and sorting of aspherical particles or cells
Designing similarity functions
Get PDFThe concept of similarity is important in many areas of cognitive science, computer science, and statistics. In machine learning, functions that measure similarity between two instances form the core of instance-based classifiers. Past similarity measures have been primarily based on simple Euclidean distance. As machine learning has matured, it has become obvious that a simple numeric instance representation is insufficient for most domains. Similarity functions for symbolic attributes have been developed, and simple methods for combining these functions with numeric similarity functions were devised. This sequence of events has revealed three important issues, which this thesis addresses.
The first issue is concerned with combining multiple measures of similarity. There is no equivalence between units of numeric similarity and units of symbolic similarity. Existing similarity functions for numeric and symbolic attributes have no common foundation, and so various schemes have been devised to avoid biasing the overall similarity towards one type of attribute. The similarity function design framework proposed by this thesis produces probability distributions that describe the likelihood of transforming between two attribute values. Because common units of probability are employed, similarities may be combined using standard methods. It is empirically shown that the resulting similarity functions treat different attribute types coherently.
The second issue relates to the instance representation itself. The current choice of numeric and symbolic attribute types is insufficient for many domains, in which more complicated representations are required. For example, a domain may require varying numbers of features, or features with structural information. The framework proposed by this thesis is sufficiently general to permit virtually any type of instance representation-all that is required is that a set of basic transformations that operate on the instances be defined. To illustrate the framework’s applicability to different instance representations, several example similarity functions are developed.
The third, and perhaps most important, issue concerns the ability to incorporate domain knowledge within similarity functions. Domain information plays an important part in choosing an instance representation. However, even given an adequate instance representation, domain information is often lost. For example, numeric features that are modulo (such as the time of day) can be perfectly represented as a numeric attribute, but simple linear similarity functions ignore the modulo nature of the attribute. Similarly, symbolic attributes may have inter-symbol relationships that should be captured in the similarity function. The design framework proposed by this thesis allows domain information to be captured in the similarity function, both in the transformation model and in the probability assigned to basic transformations. Empirical results indicate that such domain information improves classifier performance, particularly when training data is limited