Attack of the clones: an investigation into removing redundant source code

Long-term maintenance of code will often lead to the introduction of duplicated or 'cloned' code. Legacy systems riddled with these clones have large amounts of redundant code and are more difficult to understand and maintain. One option available to improve maintainability and to increase software reuse, is to re-engineer code clones into reusable components. However, before this can be achieved detection and removal of this redundant code is necessary. There are several established clone detection tools for software maintenance and this thesis aims to investigate the similarities between their output. It also looks at how maintainers may best use them to reduce the amount of redundant code in a software system. This will be achieved by running clone detection tools on several different case studies. Included in these case studies will be a novel tool called Covet inspired by research of Mayrand [May96b] which attempted to identify cloned routines through a comparison of software metrics generated from each routine. It was found that none of the clone detection tools achieved either 100% precision or 100% recall. Each tool identified very different sets of clones. Overall MOSS achieved the greatest precision and CCFinder the greatest recall. Also observed was that the use of automatically generated code increased the proportion of clones found in a software system

Web accessibility diagnosis, improvement and maintenance

Context: This thesis examines how organisations create and maintain their web pages with particular focus on ensuring pages are accessible. It also investigates the potential for using a Tree-Map based tool to support such web maintenance and process improvement. Novel process improvement recommendations are given and an adaptation of a class web publishing model is presented. Methods: To supplement a review of current literature, 20 accessibility specialists and 79 large organisations were surveyed. This identified web accessibility best practices and whether these practices were implemented in the reality. A subsequent assessment of the accessibility of each organisation's web site tested if certain activities could be linked with better accessibility. Finally, a controlled experiment tested the accuracy and efficiency of a Tree-map based tool for web maintenance. Results: The survey results suggested a wide variety of web accessibility awareness amongst web developers and accessibility specialists. Best practice appeared to be implemented by many organisations with the exception of training provision. It was found that when the best practices aimed specifically at web accessibility were implemented there was a significant improvement in web accessibility. The Tree-Map based tool was proved to be more efficient than and as accurate as report based tool for web maintenance activities. Conclusions of the study: Web accessibility awareness is now reasonably high amongst web developers but the extent to which it is addressed varies. Organisations which take a systematic and mature approach to accessibility have more accessible web sites. As such, accessibility should be integrated into web publishing. Better tools are also required to facilitate this systematic integratio

Mechanism Elucidation of Organic Reactions the Failure and Success of Rate Theories

Statistical and nonstatistical rate theories help organic chemists understand reactions. The most widely used statistical rate model is transition state theory (TST). TST is an extremely useful model for describing organic reactions; however, it has some well-known shortcomings. Despite this, reactions are often shoehorned into TST for the explanation of experimental rates and selectivities even when it is clear that TST could not account for experimental observations. Here, we present three mechanistic studies to test the validity of TST and other rate theories, including hydroboration of alkenes, thioboration of alkynes, and 1,5-hydrogen atom transfers (1,5-HAT). These were studied experimentally by the measurement of product ratios and 13C kinetic isotope effects (KIE), and computationally using dynamic trajectories, energy calculations, and tunneling approximations. The hydroboration of alkenes is a reaction that has long been described by TST; however, it has no enthalpic barrier for reaction. This leads to a nonstatistical energy distribution in the molecule. Other rate theories have been proposed, but these also fail to predict the selectivity. We propose a new nonstatistical model, which does account for the experimental selectivities. The mechanism of the formal thioboration of alkynes was studied. Through the experimental studies of kinetics and isotope effects, and computational studies, the mechanism was found to occur by simultaneous attacks to both carbons of the alkyne in an AdE3 mechanism. This reaction was determined to be governed by TST. A study of a 1,5-HAT found an extremely large H/D KIE at room temperature of 150. A KIE this large cannot be explained with TST alone, and could only be accounted for by quantum mechanical tunneling. In addition, this 1,5-HAT had a linear Eyring plot across a large range of temperatures. The normal small curvature tunneling (SCT) algorithm was insufficient to describe all of the experimental observations, but by using the large curvature tunneling (LCT) algorithm, the experimental observations were reproduced with striking accuracy

Backscattered Electron (BSE) Imaging in the Scanning Electron Microscope (SEM) - Measurement of Surface Layer Mass-Thickness

Sometimes, the sample to be examined in the SEM will consist of a compositionally non-uniform substrate that is covered by an approximately uniform surface layer. With a low enough incident beam energy, only the surface layer can be seen in the SEM image. The underlying structure can be seen in the secondary electron (SE) image if the range of the incident electrons is greater than twice the thickness of the surface film. In the backscattered electron (BSE) image the threshold energy is higher because the BSE detector is insensitive to slow electrons. The information depth in the BSE image was investigated experimentally as a function of incident energy and BSE detector position using test specimens in which an Al layer of thickness either 210 or 1,100 nm was deposited onto an aluminised Si wafer covered by a pattern of gold lines. It was estimated that a lower limit to the surface mass-thickness that can be measured using a solid-state BSE detector is ~ I0μg/cm2 (=40 nm of Al) for the BSE method, as compared with ~ 0.25 μg/cm2 (=1 nm of Al) for the low-loss electron method. There would seem to be no reason why measurements by the BSE method could not be carried out automatically in a computer-controlled SEM equipped with image analysis and using the standard BSE detector systems, to measure the mass-thickness of a surface layer

Factors influencing contraception choice and use globally: a synthesis of systematic reviews

Background: Unintended pregnancy has a huge adverse impact on maternal, child and family health and wealth. There is an unmet need for contraception globally, with an estimated 40% of pregnancies unintended worldwide. Methods: We systematically searched PubMed and specialist databases for systematic reviews addressing contraceptive choice, uptake or use, published in English between 2000 and 2019. Two reviewers independently selected and appraised reports and synthesised quantitative and qualitative review findings. We mapped emergent themes to a social determinants of health framework to develop our understanding of the complexities of contraceptive choice and use. Findings: We found 24 systematic reviews of mostly moderate or high quality. Factors affecting contraception use are remarkably similar among women in very different cultures and settings globally. Use of contraception is influenced by the perceived likelihood and appeal of pregnancy, and relationship status. It is influenced by women’s knowledge, beliefs, and perceptions of side effects and health risks. Male partners have a strong influence, as do peers’ views and experiences, and families’ expectations. Lack of education and poverty is linked with low contraception use, and social and cultural norms influence contraception and expectations of family size and timing. Contraception use also depends upon their availability, the accessibility, confidentiality and costs of health services, and attitudes, behaviour and skills of health practitioners. Interpretation: Contraception has remarkably far-reaching benefits and is highly cost-effective. However, women worldwide lack sufficient knowledge, capability and opportunity to make reproductive choices, and health care systems often fail to provide access and informed choice

Intervenção da equipe da saúde no combate a diabetes mellitus

As ações educativas são praticas inerentes ao projeto assistencial de saúde em todos os níveis de atenção. As causas de diabetes mellitus estão entre os fatores de risco modificáveis cujo controle associado a mudanças de vida pode ser estimulado no âmbito do atenção básica á saúde, minimizando a morbimortalidade por esta doença e seu impacto na saúde publica. Objetivo: Melhorar os níveis glicêmicos dos diabéticos tipo 2 da UBSF SQ 13 do município de Cidade Ocidental/GO, identificando fatores de risco para diabetes mellitus tipo 2 ,no período do projeto de intervenção e obter controle glicêmico adequado mediante aplicação de ações educativas contra os fatores de risco encontrados. Métodos: foram avaliados e acompanhados 25 pacientes da UBSF SQ 13, nos meses de setembro 2014 e maio de 2015, foram pacientes diagnosticados com diabetes desde há mais de 3 anos. A captação e coleta de amostras dos sujeitos da intervenção ocorreram nas dependências do posto de saúde SQ 13. As medições da glicemia séricas foram feitos no laboratório clinico publico em 3 ocasiões, as demais medições FDA glicemia capilar foram na UBSF SQ 13 e domicilio. As consultas foram agendadas para cada paciente cada três semanas para controle. Visitas domiciliar realizadas por medico a enfermeira e agentes de saúde de forma intercalada. As reuniões feitas em três momentos no período da intervenção com temáticas sobre diabetes e formas de tratamento, exercícios físicos e reunião de avaliação. Durantes as entrevistas individuais foram obtidos os principais fatores de risco sobre o descontrole glicêmico. Diante o acompanhamento, modificando os fatores que causam e medidas de educação em saúde, com os ajustes farmacológicos foram observadas a melhoria nas glicemias basais. A estimulação psicológica é importante para que os pacientes continuem e mantenham o tratamento continuo e o autocuidado. Alem disso a mais importante conclusão foi que a equipe organizada e determinada em resolver os problemas pode resolver situações da grande maioria sem precisar de recursos fora da unidade básica de saúde . Por tanto os resultados observados na intervenção foram satisfatórios em 92%, mostrando que os problemas ou descontrole da glicemia em sua grande maioria pode ser causadas por fatores simples, mais desencadeantes das complicações e que podem ser resolvidos a nível local

An interactive website to aid young women's choice of contraception: feasibility and efficacy RCT

Background: Effective use of contraception can reduce numbers of unintended pregnancies, but misunderstandings and concerns about contraception abound. Increasingly, women seek health-care information online.// Objectives: To develop an interactive website to aid informed choice of contraceptive method, including long-acting reversible contraception (Phase I), and test its effectiveness in a parallel, single-blind randomised trial (Phase II). Approval came from London - Camden & King's Cross Research Ethics Committee (reference 17/LO/0112).// Setting and participants: For both phases, women aged 15-30 years were recruited from general practice, sexual health services, maternity services, community pharmacies and an abortion service.// Design: In Phase I, we conducted three systematic literature reviews, a review of YouTube (YouTube, LLC, San Bruno, CA, USA) videos about contraception, and focus groups and interviews with young women to explore barriers to and concerns and misperceptions about contraception. We then iteratively co-designed an interactive website, Contraception Choices [URL: www.contraceptionchoices.org (accessed June 2020)], with young women and a software company. In Phase II, we evaluated the website through a randomised trial that began as a feasibility trial. Early demand for Contraception Choices stimulated a design change from a feasibility to an efficacy trial, with follow-up for clinical outcomes at 3 and 6 months. A randomisation list was incorporated into the trial software program to allocate participants to the intervention (website) or control group (standard care).// Intervention: Contraception Choices is a co-designed, evidence-based, interactive website to aid informed choice of contraception. It provides information about different methods, addresses common concerns and offers tailored contraceptive options in response to individual preferences.// Main outcome measures: Qualitative - participant views and experience of the intervention, assessed through qualitative interviews. Quantitative primary outcomes - follow-up rate at 6 months in the initial feasibility trial, using a long-acting reversible contraception method, and satisfaction with contraceptive method at 6 months in the efficacy trial.// Results: A total of 927 women were randomised online to the website (n = 464) or control group (n = 463), of whom 739 (80%) provided follow-up data at 6 months [786 women (85%) provided data at 3 and/or 6 months that were included in the analysis of primary outcomes]. There was little difference between groups in the proportion using long-acting reversible contraception at 6 months [30.4% intervention vs. 31.0% control, adjusted odds ratio after imputation 0.87 (95% confidence interval 0.60 to 1.27)] or in satisfaction with contraceptive method [proportion being 'satisfied' or 'very satisfied', 82.6% intervention vs. 82.1% control, adjusted odds ratio 0.93 (95% confidence interval 0.69 to 1.25)]. Qualitative evaluation indicated highly positive views about the website and increased knowledge of contraceptive methods that could dispel misperceptions. Women appreciated having information tailored to their specific needs and felt better prepared before consultations.// Limitations: We did not include intermediate measures, such as knowledge of contraceptive methods, intention to change method or confidence in discussing contraception with a health-care professional, which may have indicated other benefits of using the website. In future, the website should be studied in different settings (e.g. schools and in routine practice) to see whether or not it improves the quality or efficiency of contraceptive consultations. Conclusions: Our systematic review indicated wide-ranging influences on women's use of contraception globally. The website, Contraception Choices, was very popular with young women and contraception service providers. It was not associated with statistically significant differences in use of long-acting reversible contraception or satisfaction with contraceptive method at 6 months./

A Staged Approach to LHC Commissioning

Effective commissioning of the LHC with beam will demand very good preparation; all concerned subsystems will need to be well-prepared and thoroughly tested before first beam. To clarify the demands on the systems involved the objectives of the commissioning phases are presented, along with a breakdown of the phases and the essential prerequisites for each. The nature of the interdependencies between the various systems is highlighted; in particular the need for a well-planned commissioning of the machine protection system

Paths to Positivity: Relational Trajectories and Interaction in Positive Stepparent-Stepchild Dyads

Stepfamilies are inherently complex family systems, marked by change, flexible boundaries, and early conflict. But the developmental pathways by which long-term stepparent relationships become positive require more study. We interviewed 38 stepchildren who had reached adulthood, to understand how their relationships with a stepparent became positive. Four relational trajectories defined these positive relationships: punctuated, consistent positive, progressive incline, and modulated turbulent. Distinctive communicative practices were associated with each trajectory, such as communicating assurances, “siding,” or revelations of character. In addition, the trajectories shared three common processes: responsiveness to stepchild vulnerability, stepparent “adding value” to the family, and maturation/ reframing of the past. Findings support the existence of multiple pathways to positivity and suggest that major fluctuations are experienced along the way. Findings are interpreted in light of existing research on stepfamily development and Afifi’s theory of resilience and relational load. Recommendations are offered for stepfamilies and professionals who serve them