SACM - Australia

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    Physiological and Biochemical Differences between Diabetes Type 1 and Diabetes Type 2
    (University of New England, 2017-10-20) Almutairi, Majed; Farlane, Jim
    The expression "diabetes" is gotten from the ancient Greek word 'diabainen', which means ‘go through’, to show the too much passage of urine from the kidney. Until the 1600s it was not included, nonetheless, that Willis included the expression "mellitus" ('sweet') to recognize this condition from an unreasonable production of non-sweet urine (diabetes 'insipidus')(Poretsky, 2010). Just about 200 years after the fact (1776), Dobson showed that sweet taste of urine wasbecause of an abundance of sugar in blood and urine. Another 100 more years were needed to demonstrate the pathogenesis of diabetes mellitus. In 1889, von Mering and Minkowski showed that pancreatectomised dogs created manifestations of diabetes, thus first time connecting diabetes surprisingly to a particular organ. In 1910, Sharpey-Schafer recommended that diabetic peoples were inadequate in a substance created in the pancreatic islets (found in 1869 by Langerhans) and called it 'insulin'; in this manner, a connection between the pancreas, insulin and diabetes was begun to develop and thus modern period of diabetes study started. It was just in 1921, in any case, that a more exact picture developed: Banting, Macleod and Best demonstrated that diabetes in pancreatectomised dogs could be turned around after the intravenous organization of the "islet" extracted from typical canine ancreata. Then, Best, Banting and Collip refined this substance from bovinepancreata, and the first patient was effectively treated in 1922, bringing about a decrease in blood glucose as well as glycosuria. In 1926, MacLean recommended a difference between 'hepatic glycosuria' and 'genuine diabetes'. After ten years, Himsworth, compressing his past research, recognized 'insulin-dependent' and 'insulin-independent' diabetes mellitus, with the last more treacherous condition portrayed by less serious hyperglycaemia. In the 1950s, a solid estimation of circling insulin with a radioimmunoassay system permitted a reasonable difference between 'insulin-dependent' and 'insulin-independent' diabetes mellitus, and the worldview of two pathophysiologically distinct disordersturned out to be increasingly clear in the folowing years (Zaccardi, Webb, Yates, & Davies, 2016).
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    Plasma Fluorination of Graphene and Graphene Oxide
    (Flinders University, 2018-11-28) Alsaedi, Amal; Quinton, Jamie; Raston, Colin
    Plasma fluorination of graphene includes surface modification of graphene using plasma SF6 to modify and enhance its surface physical, electronic, and conduction properties. Experiments of plasma fluorination have been performed in the vacuum and VFD systems in this project and characterising the fluorinated graphene To develop a deep understanding of plasma fluorination process. The characterisation process involved investigating the chemical-bonding of fluorinated graphene sheets using X-ray photoelectron spectroscopy, Auger electron spectroscopy. The research also attempted to compare and contrast the results of plasma fluorinated graphene in a high vacuum environment, with the plasma fluorinated graphene using the VFD device. Based on the obtained results, the researcher will propose new, greener, and optimised fluorination route(s) that can be employed in the future when undertaking plasma fluorination of individual graphene sheets for commercial applications. In this project, Vacuum system and plasma VFD were used to produce Fluorinated graphene via plasma. Fluorination of graphene was done in the vacuum system by exposing to O2 plasma as pre-treatment and then SF6 plasma X-ray photoelectron spectroscopy, Auger electron spectroscopy were used to investigate plasma fluorination process. It was determined from the obtained results, Fluorinated graphene that produced using vacuum system was partly fluorinated, and when the time increased in order to increase the fluorination level, the damage appeared on graphene sheets and the samples in general and increased by increasing the time which could consider as a limitation for this method since it could limit the use of production from this method. Plasma fluorination was also done using plasma VFD. From the obtained results, fluorination of graphene and Graphene oxide in the plasma VFD were successful. Fluorination process of graphene after trying to eliminate the risk of HF generation by redispersing materials was not achieved since this process remove most of fluorine content. However, XPS and AES confirmed the productions of FGO in plasma VFD.
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    The Effectiveness of Virtual Reality as a Non-Pharmacological Intervention to Reduce Pain During Medical Procedures Among Adults: An Integrative Review
    (University of Sydney, 2018-06) Asiri, Salihah; West, Sandra; Betihavas, Vasiliki
    Aim: The aim of this review is to identify the effectiveness of VR as a non-pharmacological intervention to reduce pain among adult patients during medical procedures. Background: Managing pain during medical procedures is important for both patients and caregivers in providing high quality care as well as patient satisfaction. Using non-pharmacological analgesics is highly recommended due to the relative lack of side effects compared to traditional pharmacological analgesics, which can cause several side effects such as constipation, nausea, or cognitive dysfunction. These concerns, along with the associated risk of addiction, have led to limiting the use of opioids for analgesia. This review focused on using VR as a distraction method, which can be used alone or in addition to pharmacologic analgesia to reduce adult patients’ perceived pain during medical procedures. Methods: An integrative literature review was completed via a comprehensive and systematic search performed using online electronic databases, including CINAHL, PubMed, and PsycINFO via OvidSP. After the search and selection process was complete, the literature was categorized as either experimental studies of healthy participants or studies of patients undergoing various medical procedures in clinical settings. Results: Three pain components are measured while using VR in both experimental and clinical studies. These include the sensory (the intensity of pain), affective (unpleasant pain), and cognitive (time spent thinking about pain) components of pain. The amount of ‘fun’ experienced was also measured. This review suggests that the VR condition can reduce all three pain components when compared with the no VR condition, and the amount of fun experienced was increased in the VR condition. Conclusion: This paper seeks to identify the effectiveness of VR as a non-pharmacological intervention to reduce pain among adult patients during medical procedures.
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    Models for honeybee nest-site selection: a survey with cross-model comparisons
    (University of New England, 2019-12-14) Alzubaidi, Sharifah Mohammed; Schaerf, Timothy
    Throughout their lives honeybees engage in a variety of complex, cooperative, tasks that require re markable group-level coordination between thousands of worker bees. These tasks include foraging, provisioning stores and offspring, and guarding the entrance to their home. Another such task is the nest-site selection process that reproductive swarms must undertake to find and establish a new home in a limited period of time. One general way to view nest-site selection by honeybees is as a best-of-N decision-making process, where the swarm members must first find and then choose the best between many alternative sites, some of which can be at distances many kilometres from the location of the swarm, to establish a new home. The process has a finite time-limit, as reproductive swarms cannot store food, and are exposed until they establish a new home. Nest-site selection is best understood for the western hive bee, Apis mellifera, particularly due to a sequence of studies performed since 1999, but it seems that all species of honeybee apply processes with at least some similarities in choosing a new location to establish a colony. Part of the process of better understanding how the nest-site selection process of A. mellifera works has been the development and analysis of a variety of mathematical models based on current knowledge of the system at the time that the models were developed, starting with systems of nonlinear ordinary differential equations proposed by Britton et al. (2002). Since the seminal work of Britton et al. (2002), the types of models used to study nest-site selection have grown to include matrix models, individual based models, stochastic simulation models, and systems of nonlinear stochastic differential equations, across more than a dozen studies. One of the most important advances in understanding the details of nest-site selection in the last decade has been the study of the role that inhibitory stop-signals play in the overall decision-making process (Seeley et al., 2012), which required a combination of empirical observations and the analysis of an appropriate model to understand properly. As models of nest-site selection are based on the same biological process, they often include mathematical terms or algorithmic mechanisms that represent the same components of the decision making process, and that are broadly similar whilst at the same time differing in fine detail. This study is devoted to examining if differences in the details of models for nest-site selection result in quantitatively different predictions by these models. Chapter 1 provides an overview of current understanding of the real-world, biological, nest-site selection process for A. mellifera. Chapter 2 briefly details each of the current models of nest-site selection, the aspects of nest-site selection that these models have been used to examine, and the broad similarities between the models. In Chapter 3, I then chose a smaller sample of the available models for nest-site selection to examine in greater detail (one matrix model, one differential equation model and two individual based simulation models, one with relatively simple components and another that is more complex). I examine a process for choosing within-model parameters for each model so that equivalent components of the nest-site selection process will produce quantitatively similar outcomes for a standard, simplified, problem of choosing between two nest-sites - one that is of excellent quality, and another that is of poorer quality, but still acceptable. I then examine and compare the overall predictions of the models with parameters chosen so that equivalent elements of the nest-site selection process behave as similarly as possible. When parameter sets are chosen to try to maintain quantitative similarities between model components, the broad qualitative predictions of the models remain the same (with the best nest-site identified by model swarms as being the best site). However, the quantitative predictions of the models, particularly the absolute number of workers "devoted" to a particular site and some details of the system's dynamics, differ markedly across the models, in some cases by a factor of more than ten.
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    The Effects of Transport Urban Renewal: A Study of Road-Rail Level Crossings in Melbourne, Australia
    (Saudi Digital Library, 0023-11-29) Gbban, Abdulrhman; Kamruzzaman, Liton; Coxon, Selby; Dolbex, Alexa
    ABSTRACT Transport infrastructure plays a vital role in shaping and structuring urban economic, environmental, and social activities by enabling access to destinations. However, it can also pose a significant barrier for communities. Despite numerous studies documented the enabler effects of transport infrastructures, little research focuses on identifying their barrier effects (or community severance). Most of these studies, however, focus on a particular type of barrier effect (direct, indirect, or wider) using cross-sectional data, and as a result, they lack to provide causal evidence of barrier effects in a more systematic way. Studies have hypothesized that direct, indirect and wider barrier effects occur in a sequential manner. Rarely studies examined this sequential flow on barrier effects (from direct to indirect to wider) and how they vary according to the design of transport infrastructure. This study aims to address these gaps in the literature using the road-rail level crossing removal project (LXRP) in Melbourne as a case study. In particular, the study questions and objectives are: Research Question 1: To what extent does the renewal of level crossings reduce community severance directly, indirectly, and catalytically? Research Objective 1: Assess the direct barrier removal effects of rail crossing upgrade Research Objective 2: Assess the indirect barrier removal effects of rail crossing upgrade Research Objective 3: Assess the wider/catalytic barrier removal effects of rail crossing upgrade Research Question 2: What is the level of (in)consistency between objective and subjective measures of barrier removal effects caused by the renewal of level crossings? Research Objective 4: Assess the consistency of the objective and subjective measures of the wider barrier removal effects. To answer the research questions, a combination of quantitative and qualitative data collection methods was employed. Qualitative data was used to understand the perceived barrier removal effects of LXRPs from the perspective of residents, whereas quantitative data complemented the qualitative data to objectively measure the wider barrier removal effects of LXRPs. A quasi-panel design was utilized in this study to assess the impact of infrastructure upgrades on residents' perceptions of their urban environment. An online questionnaire survey was designed to collect qualitative data from 776 residents living around 13 LXRP sites (cases) and 13 control sites. The questionnaire captured residents' perceptions of changes in the patterns of walking and cycling, travel time, and social life within their neighborhoods, respectively representing direct, indirect, and wider barrier removal v effects. Kruskal-Wallis and Mann-Whitney U tests were used to understand if the reported changes were significantly different between the case and control sites. Quantitative data collection involved the extraction of land use data from satellite images in the case and control sites in 2015 (pre-LXRP) and 2020 (post-LXRP). The case-control study design ensured that the observed changes in land use patterns in the LXRP sites were not due to chance (e.g. external effects). A difference-in-difference method was employed to robustly infer about the causal impacts of LXRPs on land use patterns. Furthermore, the gathering of both qualitative and quantitative data enabled the study to evaluate the degree of consistency between the two measures. This evaluation was conducted using the %agreement analysis to assess the level of agreement between these two types of measures. The survey data indicate that the removal of level crossing barriers resulted in: a) an enjoyment of walking and cycling in the communities (direct effects); b) a reduction in cycling time to workplaces, shops and restaurants, and schools (indirect effects); and c) an increase in open spaces and commercial use, and a decrease in residential areas (wider effects). Note, however, that some of the positive effects were found only when the new infrastructure was built above the ground suggesting the significant effects of infrastructure design on barrier removal effects. The %agreement analysis results, however show that while there is a considerable agreement between the objective and subjective measures in the perception of changes in shops and restaurants, parking lots and public buildings, noticeable inconsistencies exist in the measurement of houses and apartments, vacant lots and industrial buildings. This thesis, for the first time, provides causal evidence of barrier removal effects of transport infrastructure and how these can be observed in a sequential order from direct to indirect to wider. The findings are encouraging for transport authorities aiming to reduce barrier effects for communities. It also provides evidence of the effective ways of reducing the barrier effects through the design of infrastructure (above the ground vs. underground). However, the discrepancy between the objective and subjective measures suggests that residents are unaware of the positive impacts that LXRPs are making on the communities. This can be achieved, for example, through communication strategies.
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    The Effect of Physical Exercise as an Adjunctive Treatment to the Usual Treatment for Major Depressive Disorder: An Integrative Review
    (Saudi Digital Library, 2017) Alsolami, Eman; West, Sandra; Betihavas, Vasiliki
    Major depressive disorder (MDD) is a leading cause of disability around the world. The current treatment approach for MDD is limited. Physical exercise is a suggested treatment for depression and the use of exercise as an adjunctive therapy to the usual treatment of depression has received significant attention. The aim of this thesis is to evaluate whether physical exercise as an adjunctive therapy leads to an extra reduction in depressive symptoms compared with using the usual treatments alone. An integrative review was conducted by a systematic search in Scopus and PsycINFO databases. The search yielded 100articles, which were narrowed to 15 articles based on inclusion and exclusion criteria. The review found that using exercise as an adjunctive therapy to the usual treatment of depression decreased depressive symptoms more than using the usual treatment alone. It also found that this effect is not influenced by factors such as type of exercise, as aerobic and resistance exercise lead to the same effect. In addition, it found that exercise programs of short- and medium-duration were more effective than programs of a longer duration, and that hospital- and public-based exercise were more effective than home-based exercise. However, this review cannot determine whether the effect of using exercise as an adjunctive therapy to the usual treatments might be different based on the severity of depression and the patient’s age. This review suggests that using short and moderate programs of exercise as an adjunctive therapy to the usual treatment of depression can be an effective way to improve the depressive symptoms among adult patients with MDD.
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    Electrical resistance measurements of silver nanowire junctions using Conductive Atomic Force Microscopy
    (Saudi Digital Library, 2017-09-25) Alzahrani, Sanaa Abdullah M; Hoxley, David; Langley, Daniel
    Transparent conductive materials (TCMs) are in high demand for widespread applications, including organic light-emitting diode displays, touch panels, solar cells. TCMs have conventionally been made from indium tin oxide (ITO) as it offers high electrical conductivity and transparency. However, as a brittle ceramic, its usage in future applications in building flexible electronic devices has become limited. Networks of silver nanowires (AgNWs) are an alternative TCM material, displaying flexibility and high optical transmittance. However, their low sheet resistance relies on minimizing the contact resistance between individual silver nanowires, which remains a major challenge. We have used an Atomic Force Microscope (AFM) to measuring the electrical resistance of individual nanowire junctions and conducting pathways in networks deposited on glass substrates. It was found that mechanical pressing at room temperature improves the electrical conductivity of the AgNW networks, but considerable resistance remains. This is attributed to residual layer of organic contamination from the dispersants used in the films formation process. Possible treatments to reduce this are discussed.
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    X-Ray Imaging of Nanostructured Silicon Thin-Film Anodes for Lithium-Ion Batteries
    (Saudi Digital Library, 2017-12-05) Alomari, Suaad; Van Riessen, Grant; Arhatari, Benedicta
    Nanostructured silicon is one of the most promising anode materials for high energy density lithium ion batteries. However, the degradation that occurs as a result of a large volume change during the lithiation/delithiation cycle hinders commercial application. The mechanism of degradation, the charge capacity, and the charge/discharge performance of silicon anodes are strong functions of microstructure and nanostructure. Therefore, it is important to develop methods of characterising silicon anodes at these structural length scales. The objective of this study is to explore X-ray based methods that can potentially be applied for in operando studies of model Li-ion batteries during charge and discharge cycles. This is of great importance for the rational design of future high performance silicon anodes. A process for fabricating nonoporous, thin film silicon was developed. The process, based on magnetron sputtering of phosphorous doped silicon and reactive ion etching, was shown to produce nanoporous films with structure that depends on the reactive ion etching parameters. This process was integrated into a scheme for fabricating microscale Li-ion batteries that are compatible with optical and X-ray microscopy. After determining that phase contrast imaging using laboratory sources can not provide the sensitivity required to characterise variations in thin-film anode structures, we evaluated the potential of synchrotron based ptychographic Fresnel coherent diffractive imaging (FCDI) using soft x-rays. In this experiment, we studied the nanostructure of the amorphous silicon film before and after deposition of a LiPF6 electrolyte solution. The coherent diffraction intensity was weak but clearly showed characteristics consistent with the expected nanostructure of the Si film. The characteristic nanostructure of the dry silicon film in coherent diffraction patterns was not observed after electrolyte deposition. While the cause for this difference is not fully understood and remains the subject for future work, the role of the electrolyte in reducing sensitivity to the nanoscale structure of the silicon, and the possibility of it inducing structural changes upon contact are considered. Quantitative phase and magnitude images of representative areas of the dry Si anode were successfully reconstructed from the ptychographic FCDI data. These results indicate that FCDI using synchrotron radiation has the required sensitivity for studying changes in the nanostructure of thin-film silicon anodes and we use the data obtained to evaluate the potential for in operando studies of dynamic processes occurring during electrochemical operation.
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    Examining Academics and Students Attitudes to Mobile-learning in a Transformative University in the Kingdom of Saudi Arabia: a study of Imam Abdulrahman Bin Faisal University
    (Saudi Digital Library, 0023-10-27) Alshehri, Eman; Preston, Greg; Buchanan, Rachel
    Although there is a growing interest in mobile-learning and its potential benefits in higher education, limited research has investigated cross-contextual mobile-learning issues such as university technology policies, usage levels, and practices in relation to students' gender, contextual, educational, and gender-based mobile-learning attitudes. This study was undertaken as a case study at Imam Abdulrahman Bin Faisal University (IAU), to investigate the attitudes of both academic staff and students towards the adoption of mobile-learning with Smartphones. The first purpose of this study was to explore the current Smartphone policies, level of usage, preferred learning activities by students and academics at IAU. The second purpose of the study was to investigate the student’s and academics’ attitudes and perceptions toward using their Smartphones as learning and teaching tools, with particular regard to the challenges and/or enablers that they may encounter. This study used an adapted version of the Technology Acceptance Model (TAM) and a sequential mixed methods design to collect the data using online surveys with students (N=325), and semi-structured interviews with academics (N=21). Regression analysis was used to analyse the online surveys (quantitative data), and a thematic analysis was used to analyse the semi-structured interviews (qualitative data). The study findings revealed that both students and academics generally have a positive attitude toward the use of Smartphones in the learning environment at IAU. Around 98% of students at IAU use Smartphones every day for learning, while the use by the academics was substantially less. From the nine measured variables, only four predictors had a significant influence on students’ attitudes to mobile-learning: self-efficacy, enjoyment, perceived ease of use, and mobile-learning preferences. For academics, the most frequently reported challenge they faced when adopting mobile-learning was the lack of policies and regulations governing their use. This study contributes to the body of knowledge on mobile-learning in higher education and offers useful insights into how Smartphones are currently used by students and academics at IAU and the best practices for implementing Smartphones as learning and teaching tools.
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    Exploring teachers’ and students’ efficacy in the teaching and learning of English as a Foreign Language (EFL) in Saudi Arabia
    (Saudi Digital Library, 0023-06-06) Alkhairi, Ahmad Hassan E; Alkhairi, Ahmad
    This qualitative case study explored teaching and learning practices of English-as-a Foreign Language (EFL) in the school context in Kingdom of Saudi Arabia (KSA). The study is underpinned by Bandura’s (1977, 1986) triadic reciprocal causation model, derived from his Social Cognitive Theory. In particular, the research focused on the teacher-efficacy of Saudi EFL teachers and the self-efficacy of students learning the English language. The approach of the research explores self-efficacy through a qualitative method. Data were collected through individual semi-structured interviews with secondary school teachers and through focus group discussions with their students, through classroom observations, and through examination of teaching materials to comprehend the teaching and learning environment of EFL in Saudi schools.
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