Adaptive radiotherapy for virally mediated head and neck cancer

Purpose: Virally mediated head and neck cancers (VMHNC) often present with nodal involvement, and are generally considered radioresponsive, resulting in the need for a re-planning CT during radiotherapy (RT) in a subset of patients. We sought to identify a high-risk group based on nodal size to be evaluated in a future prospective adaptive RT trial. Methodology: Between 2005-2010, 121 patients with virally-mediated, node positive nasopharyngeal (EBV positive) or oropharyngeal (HPV positive) cancers, receiving curative intent RT were reviewed. Patients were analysed based on maximum size of the dominant node with a view to grouping them in varying risk categories for the need of re-planning. The frequency and timing of the re-planning scans were also evaluated. Results: Sixteen nasopharyngeal and 105 oropharyngeal tumours were reviewed. Twenty-five (21%) patients underwent a re-planning CT at a median of 22 (range, 0-29) fractions with 1 patient requiring re-planning prior to the commencement of treatment. Based on the analysis, patients were subsequently placed into 3 groups; ≤35mm (Group 1), 36-45mm (Group 2), ≥46mm (Group 3). Re-planning CT’s were performed in Group 1- 8/68 (11.8%), Group 2- 4/28 (14.3%), Group 3- 13/25 (52%). Sample size did not allow statistical analysis to detect a significant difference or exclusion of a lack of difference between the 3 groups. Conclusion: In this series, patients with VMHNC and nodal size > 46mm appear to be a high-risk group for the need of re-planning during a course of definitive radiotherapy. This finding will now be tested in a prospective adaptive RT study.

Adaptive radiotherapy for virally mediated head and neck cancer

Purpose: Virally mediated head and neck cancers (VMHNC) often present with nodal involvement, and are generally considered radioresponsive, resulting in the need for plan adaptation during radiotherapy in a subset of patients. We sought to identify a high-risk group based on pre-treatment nodal size to be evaluated in a future prospective adaptive radiotherapy trial. Methodology: Between 2005-2010, 121 patients with virally-mediated, node positive nasopharyngeal or oropharyngeal cancers, receiving definitive radiotherapy were reviewed. Patients were analysed based on maximum size of the dominant node at diagnosis with a view to grouping them in varying risk categories for the need of re-planning. The frequency and timing of the re-planning scans were also evaluated. Results: Sixteen nasopharyngeal and 105 oropharyngeal tumours were reviewed. Twenty-five (21%) patients underwent a re-planning CT at a median of 22 (range, 0-29) fractions with 1 patient requiring re-planning prior to the commencement of treatment. Based on the analysis, patients were subsequently placed into 3 groups defined by pre-treatment nodal size; ≤ 35mm (Group 1), 36-45mm (Group 2), ≥ 46mm (Group 3). Applying these groups to the patient cohort, re-planning CT’s were performed in Group 1- 8/68 (11.8%), Group 2- 4/28 (14.3%), Group 3- 13/25 (52%). Conclusion: In this series, patients with VMHNC and nodal size > 46mm appear to be a high-risk group for the need of plan adaptation during a course of definitive radiotherapy. This finding will now be tested in a prospective adaptive radiotherapy study.

Calcite precipitation induced by clay-bleach cation exchange in andesitic reservoir rocks

Experiments were carried out on the sodium hypochlorite bleach sensitivity of a deep subsurface andesitic reservoir in order to predict possible deleterious mineral transformations during a downhole clean-up job. Experiments involved examination of core samples from the reservoir using an Environmental Scanning Electron Microscope (ESEM) with an attached Energy Dispersive Spectrometer (EDS) before and after the samples were immersed in bleach. Bleach immersion of whole-rock samples resulted in rapid (less than 1 min) precipitation of abundant 3.0-10.0-μm-wide calcite rhombs within clay-associated micropores and on clay and feldspar grain surfaces. Abundant microporefilling calcite rhombs also formed in pure separates of constituent chlorite/corrensite, whereas no calcite formed in a pure separate of constituent zeolite. These experiments indicate that corrensite is the likely calcium source in this experimental fluid-rock system. Formation of calcite occurs via a cation exchange reaction in which calcium in the smectitic interlayers of corrensite exchanges for sodium in the bleach. Serious formation damage due to calcite precipitation would have occurred in the andesite reservoir had it been exposed to bleach. This finding gives credence to earlier suggestions that cation exchange reactions have the potential to cause calcite precipitation in some sandstone reservoirs when exposed to drilling, completion or stimulation fluids. © 1993.

Reputation modelling in Citizen Science for environmental acoustic data analysis

Citizen Science projects are initiatives in which members of the general public participate in scientific research projects and perform or manage research-related tasks such as data collection and/or data annotation. Citizen Science is technologically possible and scientifically significant. However, although research teams can save time and money by recruiting general citizens to volunteer their time and skills to help data analysis, the reliability of contributed data varies a lot. Data reliability issues are significant to the domain of Citizen Science due to the quantity and diversity of people and devices involved. Participants may submit low quality, misleading, inaccurate, or even malicious data. Therefore, finding a way to improve the data reliability has become an urgent demand. This study aims to investigate techniques to enhance the reliability of data contributed by general citizens in scientific research projects especially for acoustic sensing projects. In particular, we propose to design a reputation framework to enhance data reliability and also investigate some critical elements that should be aware of during developing and designing new reputation systems.

The state-of-the-art in personalized recommender systems for social networking

With the explosion of Web 2.0 application such as blogs, social and professional networks, and various other types of social media, the rich online information and various new sources of knowledge flood users and hence pose a great challenge in terms of information overload. It is critical to use intelligent agent software systems to assist users in finding the right information from an abundance of Web data. Recommender systems can help users deal with information overload problem efficiently by suggesting items (e.g., information and products) that match users’ personal interests. The recommender technology has been successfully employed in many applications such as recommending films, music, books, etc. The purpose of this report is to give an overview of existing technologies for building personalized recommender systems in social networking environment, to propose a research direction for addressing user profiling and cold start problems by exploiting user-generated content newly available in Web 2.0.

Taxonomic revision of Ustilago, Sporisorium and Macalpinomyces

The three genera of smut fungi, Ustilago, Sporisorium and Macalpinomyces, form a complex that has eluded resolution by morphology (Langdon & Fullerton 1975, Vánky 1991, Piepenbring et al. 1998) and molecular phylogenetic analysis (Stoll et al. 2003, 2005). Two suggestions to reconcile the taxonomy of the complex have been proposed. The first was to break up the current taxa into several smaller genera and subgenera, and the second to unify the three genera into a single genus, Ustilago (Vánky 2002, Piepenbring 2004). The former solution is dependent on finding morphological synapomorphies that can delimit the genera, and the latter solution dismisses the wide morphological diversity within the group (McTaggart et al. 2012b). Synapomorphic morphological characters and host plant classification delimited clades in the Ustilago-Sporisorium-Macalpinomyces complex (McTaggart et al. 2012a). The current study defines these synapomorphic characters and proposes a new classification for many species currently placed in Ustilago, Sporisorium and Macalpinomyces. This approach preserves the well-known genera Ustilago, Sporisorium and Macalpinomyces, and enables the classification to reflect morphological diversity in the complex.

Analysis of environmental efficiency variation : a materials balance approach

Recent literature has argued that environmental efficiency (EE), which is built on the materials balance (MB) principle, is more suitable than other EE measures in situations where the law of mass conversation regulates production processes. In addition, the MB-based EE method is particularly useful in analysing possible trade-offs between cost and environmental performance. Identifying determinants of MB-based EE can provide useful information to decision makers but there are very few empirical investigations into this issue. This article proposes the use of data envelopment analysis and stochastic frontier analysis techniques to analyse variation in MB-based EE. Specifically, the article develops a stochastic nutrient frontier and nutrient inefficiency model to analyse determinants of MB-based EE. The empirical study applies both techniques to investigate MB-based EE of 96 rice farms in South Korea. The size of land, fertiliser consumption intensity, cost allocative efficiency, and the share of owned land out of total land are found to be correlated with MB-based EE. The results confirm the presence of a trade-off between MB-based EE and cost allocative efficiency and this finding, favouring policy interventions to help farms simultaneously achieve cost efficiency and MP-based EE.

Analysis of productive performance of crop production systems: an integrated analytical framework

Recent literature has argued that environmental efficiency (EE), which is built on the materials balance (MB) principle, is more suitable than other EE measures in situations where the law of mass conversation regulates production processes. In addition, the MB-based EE method is particularly useful in analysing possible trade-offs between cost and environmental performance. Identifying determinants of MB-based EE can provide useful information to decision makers but there are very few empirical investigations into this issue. This article proposes the use of data envelopment analysis and stochastic frontier analysis techniques to analyse variation in MB-based EE. Specifically, the article develops a stochastic nutrient frontier and nutrient inefficiency model to analyse determinants of MB-based EE. The empirical study applies both techniques to investigate MB-based EE of 96 rice farms in South Korea. The size of land, fertiliser consumption intensity, cost allocative efficiency, and the share of owned land out of total land are found to be correlated with MB-based EE. The results confirm the presence of a trade-off between MB-based EE and cost allocative efficiency and this finding, favouring policy interventions to help farms simultaneously achieve cost efficiency and MP-based EE.

Characterization of in vitro Chlamydia muridarum persistence and utilization in an in vivo mouse model of Chlamydia vaccine

Problem: Chlamydia trachomatis genital tract infections are easily treated with antibiotics, however the majority of infections are asymptomatic and therefore untreated, highlighting the need for a vaccine. Because most infections are asymptomatic, vaccination could potentially be administered to individuals who may have an acute infection at that time. In such individuals the effect of vaccination on the existing infection is unknown; however one potential outcome could be the development of a persistent infection. In vitro chlamydial persistence has been well characterized in various strains, however there have been no reported studies in C. muridarum. Method of Study: We performed ultrastructural characterization, and transcriptome analysis of selected genes. We then used the transcriptional profiles of the selected genes to examine whether intranasal immunization of mice during an active genital infection would induce persistence in the upper reproductive tract of female mice. Results and Conclusions: We found that persistence developed in the oviducts of mice as a result of immunization. This is a significant finding, not only because it is the first time that C. muridarum persistence has been characterized in vitro, but also due to the fact that there is minimal characterization of in vivo persistence of any chlamydial species. This highlights the importance of the timing of vaccination in individuals.

Perceptions of visitor relationship marketing opportunities by destination marketers : an importance-performance analysis

Customer relationship marketing (CRM) initiatives are increasingly being adopted by businesses in the attempt to enhance brand loyalty and stimulate repeat purchases. The purpose of this study was to examine the extent to which destination marketing organisations (DMOs) around the world have developed a visitor relationship marketing (VRM) orientation. The proposition underpinning the study is that maintaining meaningful dialogue with previous visitors in some markets would represent a more efficient use of resources than above the line advertising to attract new visitors. Importance-performance analysis was utilised to measure destination marketers’ perceptions of the efficacy of CRM initiatives, and then rate their own organisation’s performance across the same range of initiatives. A key finding was that mean importance was higher than perceived performance for every item. While the small sample limits generalisability, in general there are appears to be a lack of strategic intent by DMOs to invest in VRM.

Assisting a suicide : potential succession law consequences

The recent criminal law decisions where people have been convicted of aiding suicide raise important legal and ethical issues in relation to whether euthanasia should be legalised. These cases also raise issues of great significance for succession lawyers. Where, as in cases such as Nielsen and Justins, the person convicted of aiding a suicide is a principal beneficiary under the will of the deceased, various legal consequences, such as: forfeiture of the interest under the will; liability for breach of fiduciary obligation; and/or a finding of undue influence, may follow which may result in loss of such benefit.

Representation of assertions in clinical free-­text using SNOMED CT

Information retrieval (IR) by clinicians in the healthcare setting is critical for informing clinical decision-making. However, a large part of this information is in the form of free-text and inhibits clinical decision support and effective healthcare services. This makes meaningful use of clinical free-­text in electronic health records (EHRs) for patient care a difficult task. Within the context of IR, given a repository of free-­text clinical reports, one might want to retrieve and analyse data for patients who have a known clinical finding.

Semantic labelling for document feature patterns using ontological subjects

Finding and labelling semantic features patterns of documents in a large, spatial corpus is a challenging problem. Text documents have characteristics that make semantic labelling difficult; the rapidly increasing volume of online documents makes a bottleneck in finding meaningful textual patterns. Aiming to deal with these issues, we propose an unsupervised documnent labelling approach based on semantic content and feature patterns. A world ontology with extensive topic coverage is exploited to supply controlled, structured subjects for labelling. An algorithm is also introduced to reduce dimensionality based on the study of ontological structure. The proposed approach was promisingly evaluated by compared with typical machine learning methods including SVMs, Rocchio, and kNN.

Empirical study to identify the key business activities contributing to manufacturing business performance

Purpose: Within the context of high global competitiveness, knowledge management (KM) has proven to be one of the major factors contributing to enhanced business outcomes. Furthermore, knowledge sharing (KS) is one of the most critical of all KM activities. From a manufacturing industry perspective, supply chain management (SCM) and product development process (PDP) activities, require a high proportion of company resources such as budget and manpower. Therefore, manufacturing companies are striving to strengthen SCM, PDP and KS activities in order to accelerate rates of manufacturing process improvement, ultimately resulting in higher levels of business performance (BP). A theoretical framework along with a number of hypotheses are proposed and empirically tested through correlation, factor and path analyses. Design/methodology/approach: A questionnaire survey was administered to a sample of electronic manufacturing companies operating in Taiwan to facilitate testing the proposed relationships. More than 170 respondents from 83 organisations responded to the survey. The study identified top management commitment and employee empowerment, supplier evaluation and selection, and design simplification and modular design as the key business activities that are strongly associated with the business performance. Findings: The empirical study supports that key manufacturing business activities (i.e., SCM, PDP, and KS) are positively associated with BP. The findings also evealed that some specific business activities such as SCMF1,PDPF2, and KSF1 have the strongest influencing power on particular business outcomes (i.e., BPF1 and BPF2) within the context of electronic manufacturing companies operating in Taiwan. Practical implications: The finding regarding the relationship between SCM and BP identified the essential role of supplier evaluation and selection in improving business competitiveness and long term performance. The process of forming knowledge in companies, such as creation, storage/retrieval, and transfer do not necessarily lead to enhanced business performance; only through effectively applying knowledge to the right person at the right time does. Originality/value: Based on this finding it is recommended that companies should involve suppliers in partnerships to continuously improve operations and enhance product design efforts, which would ultimately enhance business performance. Business performance depends more on an employee’s ability to turn knowledge into effective action.

Link discovery for Chinese/English cross-language web information retrieval

Nowadays people heavily rely on the Internet for information and knowledge. Wikipedia is an online multilingual encyclopaedia that contains a very large number of detailed articles covering most written languages. It is often considered to be a treasury of human knowledge. It includes extensive hypertext links between documents of the same language for easy navigation. However, the pages in different languages are rarely cross-linked except for direct equivalent pages on the same subject in different languages. This could pose serious difficulties to users seeking information or knowledge from different lingual sources, or where there is no equivalent page in one language or another. In this thesis, a new information retrieval task—cross-lingual link discovery (CLLD) is proposed to tackle the problem of the lack of cross-lingual anchored links in a knowledge base such as Wikipedia. In contrast to traditional information retrieval tasks, cross language link discovery algorithms actively recommend a set of meaningful anchors in a source document and establish links to documents in an alternative language. In other words, cross-lingual link discovery is a way of automatically finding hypertext links between documents in different languages, which is particularly helpful for knowledge discovery in different language domains. This study is specifically focused on Chinese / English link discovery (C/ELD). Chinese / English link discovery is a special case of cross-lingual link discovery task. It involves tasks including natural language processing (NLP), cross-lingual information retrieval (CLIR) and cross-lingual link discovery. To justify the effectiveness of CLLD, a standard evaluation framework is also proposed. The evaluation framework includes topics, document collections, a gold standard dataset, evaluation metrics, and toolkits for run pooling, link assessment and system evaluation. With the evaluation framework, performance of CLLD approaches and systems can be quantified. This thesis contributes to the research on natural language processing and cross-lingual information retrieval in CLLD: 1) a new simple, but effective Chinese segmentation method, n-gram mutual information, is presented for determining the boundaries of Chinese text; 2) a voting mechanism of name entity translation is demonstrated for achieving a high precision of English / Chinese machine translation; 3) a link mining approach that mines the existing link structure for anchor probabilities achieves encouraging results in suggesting cross-lingual Chinese / English links in Wikipedia. This approach was examined in the experiments for better, automatic generation of cross-lingual links that were carried out as part of the study. The overall major contribution of this thesis is the provision of a standard evaluation framework for cross-lingual link discovery research. It is important in CLLD evaluation to have this framework which helps in benchmarking the performance of various CLLD systems and in identifying good CLLD realisation approaches. The evaluation methods and the evaluation framework described in this thesis have been utilised to quantify the system performance in the NTCIR-9 Crosslink task which is the first information retrieval track of this kind.