658 resultados para 250699 Theoretical and Computational Chemistry not elsewhere classified
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Although robotics research has seen advances over the last decades robots are still not in widespread use outside industrial applications. Yet a range of proposed scenarios have robots working together, helping and coexisting with humans in daily life. In all these a clear need to deal with a more unstructured, changing environment arises. I herein present a system that aims to overcome the limitations of highly complex robotic systems, in terms of autonomy and adaptation. The main focus of research is to investigate the use of visual feedback for improving reaching and grasping capabilities of complex robots. To facilitate this a combined integration of computer vision and machine learning techniques is employed. From a robot vision point of view the combination of domain knowledge from both imaging processing and machine learning techniques, can expand the capabilities of robots. I present a novel framework called Cartesian Genetic Programming for Image Processing (CGP-IP). CGP-IP can be trained to detect objects in the incoming camera streams and successfully demonstrated on many different problem domains. The approach requires only a few training images (it was tested with 5 to 10 images per experiment) is fast, scalable and robust yet requires very small training sets. Additionally, it can generate human readable programs that can be further customized and tuned. While CGP-IP is a supervised-learning technique, I show an integration on the iCub, that allows for the autonomous learning of object detection and identification. Finally this dissertation includes two proof-of-concepts that integrate the motion and action sides. First, reactive reaching and grasping is shown. It allows the robot to avoid obstacles detected in the visual stream, while reaching for the intended target object. Furthermore the integration enables us to use the robot in non-static environments, i.e. the reaching is adapted on-the- fly from the visual feedback received, e.g. when an obstacle is moved into the trajectory. The second integration highlights the capabilities of these frameworks, by improving the visual detection by performing object manipulation actions.
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- Objective Driver sleepiness is a major crash risk factor, but may be under-recognized as a risky driving behavior. Sleepy driving is usually rated as less of a road safety issue than more well-known risky driving behaviors, such as drink driving and speeding. The objective of this study was to compare perception of crash risk of sleepy driving, drink driving, and speeding. - Methods In total, 300 Australian drivers completed a questionnaire that assessed crash risk perceptions for sleepy driving, drink driving, and speeding. Additionally, the participants perception of crash risk was assessed for five different contextual scenarios that included different levels of sleepiness (low, high), driving duration (short, long), and time of day/circadian influences (afternoon, night-time) of driving. - Results The analysis confirmed that sleepy driving was considered a risky driving behavior, but not as risky as high levels of speeding (p < .05). Yet, the risk of crashing at 4 am was considered as equally risky as low levels of speeding (10 km over the limit). The comparisons of the contextual scenarios revealed driving scenarios that would arguably be perceived as quite risky due to time of day/circadian influences were not reported as high risk. - Conclusions The results suggest a lack of awareness or appreciation of circadian rhythm functioning, particularly the descending phase of circadian rhythm that promotes increased sleepiness in the afternoon and during the early hours of the morning. Yet, the results suggested an appreciation of the danger associated with long distance driving and driver sleepiness. Further efforts are required to improve the community’s awareness of the impairing effects from sleepiness and in particular, knowledge regarding the human circadian rhythm and the increased sleep propensity during the circadian nadir.
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Neutral capsular polysaccharides (CPSs) were isolated from Acinetobacter baumannii NIPH190, NIPH201, and NIPH615. The CPSs were found to contain common monosaccharides only and to be branched with a side-chain 1→3-linked β-d-glucopyranose residue. Structures of the oligosaccharide repeat units (K units) of the CPSs were elucidated by 1D and 2D 1H and 13C NMR spectroscopy. Novel CPS biosynthesis gene clusters, designated KL30, KL45, and KL48, were found at the K locus in the genome sequences of NIPH190, NIPH201, and NIPH615, respectively. The genetic content of each gene cluster correlated with the structure of the CPS unit established, and therefore, the capsular types of the strains studied were designated as K30, K45, and K48, respectively. The initiating sugar of each K unit was predicted, and glycosyltransferases encoded by each gene cluster were assigned to the formation of the linkages between sugars in the corresponding K unit.
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A profluorescent nitroxide possessing an isoindoline nitroxide moiety linked to a perylene fluorophore was developed to monitor radical mediated degradation of melamine-formaldehyde crosslinked polyester coil coatings in an industry standard accelerated weathering tester. Trapping of polyester-derived radicals (most likely C-radicals) that are generated during polymer degradation leads to fluorescent closed-shell alkoxy amines, which was used to obtain time-dependent degradation profiles to assess the relative stability of different polyesters towards weathering. The nitroxide probe couples excellent thermal stability and satisfactory photostability with high sensitivity and enables detection of free radical damage in polyesters under conditions that mimic exposure to the environment on a time scale of hours rather than months or years required by other testing methods. There are indications that the profluorescent nitroxide undergoes partial photo-degradation in the absence of polymer-derived radicals. Unexpectedly, it was also found that UV-induced fragmentation of the NO–C bond in closed-shell alkoxy amines leads to regeneration of the profluorescent nitroxide and the respective C-radical. The maximum fluorescence intensity that could be achieved with a given probe concentration is therefore not only determined by the amount of polyester radicals formed during accelerated weathering, but also by the light-driven side reactions of the profluorescent nitroxide and the corresponding alkoxy amine radical trapping products. Studies to determine the optimum probe concentration in the polymer matrix revealed that aggregation and re-absorption effects lowered the fluorescence intensity at higher concentrations of the profluorescent nitroxide, but too low probe concentrations, where these effects would be avoided, were not sufficient to trap the amount of polyester radicals formed upon weathering. The optimized experimental conditions were used to assess the impact of temperature and UV irradiance on polymer degradation during accelerated weathering.
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Sit-to-stand (STS) tests measure the ability to get up from a chair, reproducing an important component of daily living activity. As this functional task is essential for human independence, STS performance has been studied in the past decades using several methods, including electromyography. The aim of this study was to measure muscular activity and fatigue during different repetitions and speeds of STS tasks using surface electromyography in lower-limb and trunk muscles. This cross-sectional study recruited 30 healthy young adults. Average muscle activation, percentage of maximum voluntary contraction, muscle involvement in motion and fatigue were measured using surface electrodes placed on the medial gastrocnemius (MG), biceps femoris (BF), vastus medialis of the quadriceps (QM), the abdominal rectus (AR), erector spinae (ES), rectus femoris (RF), soleus (SO) and the tibialis anterior (TA). Five-repetition STS, 10-repetition STS and 30-second STS variants were performed. MG, BF, QM, ES and RF muscles showed differences in muscle activation, while QM, AR and ES muscles showed significant differences in MVC percentage. Also, significant differences in fatigue were found in QM muscle between different STS tests. There was no statistically significant fatigue in the BF, MG and SO muscles of the leg although there appeared to be a trend of increasing fatigue. These results could be useful in describing the functional movements of the STS test used in rehabilitation programs, notwithstanding that they were measured in healthy young subjects.
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Background Surgery is an example of expanded practice scope that enhances podiatry and incorporates inter-professional collaboration. By 2050 demand for foot and ankle procedures is predicted to rise nationally by 61.9%. Performance management of this increase motivated the development of an online audit tool. Developed in collaboration with the Australasian College of Podiatric Surgeons (ACPS), the ACPS audit tool provides real-time data capture and reporting. It is the first audit tool designed in Australia to support and improve the outcomes of foot and ankle surgery. Methods Audit activity in general, orthopaedic, plastic and podiatric surgery was examined using a case study design. Audit participation enablers and barriers were explored. Case study results guided a Delphi survey of international experts experienced or associated with foot and ankle surgery. Delphi survey-derived consensus informed modification of a generic data set from the Royal Australasian College of Surgeons (RACS). Based on the Delphi survey findings the ACPS online audit tool was developed and piloted. Reliability and validity of data entry and usability of this new tool was then assessed with an online survey. Results The case study found surgeon attitudes and behaviours positively impacted audit participation, and also indicated that audit data should be: (1) available in real time, (2) identify practice change, (3) applicable for safety and quality management, and; (4) useful for peer review discussion. The Delphi process established consensus on audit variables to be captured, including the modified RACS generic data set. 382 cases of foot and ankle surgery were captured across 3 months using the new tool. Data entry was found to be valid and reliable. Real-time outcome reporting and practice change identification impacted positively on safety and quality management and assisted peer review discussion. An online survey showed high levels of usability. Conclusions Surgeon contribution to audit tool development resulted in 100% audit participation. The data from the ACPS audit tool supported the ACPS submission to the Medical Services Advisory Committee to list podiatric surgery under Medicare, an outcome noted by the Federal Minister of Health.
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Characterization of indoor air quality in school classrooms is crucial to children’s health and performance. The present study was undertaken to characterize the indoor air quality in six naturally ventilated classrooms of three schools in Cassino (Italy). Indoor particle number, mass, black carbon, CO2 and radon concentrations, as well as outdoor particle number were measured within school hours during the winter and spring season. The study found the concentrations of indoor particle number were influenced by the concentrations in the outdoors; highest BC values were detected in classrooms during peak traffic time. The effect of different seasons’ airing mode on the indoor air quality was also detected. The ratio between indoor and outdoor particles was of 0.85 ± 0.10 in winter, under airing conditions of short opening window periods, and 1.00 ± 0.15 in spring when the windows were opened for longer periods. This was associated to a higher degree of penetration of outdoor particles due to longer period of window opening. Lower CO2 levels were found in classrooms in spring (908 ppm) than in winter (2206 ppm). Additionally, a greater reduction in radon concentrations was found in spring. In addition, high PM10 levels were found in classrooms during break time due to re-suspension of coarse particles. Keywords: classroom; Ni/Nout ratio; airing by opening windows; particle number
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This qualitative study investigated the refugee journey of 17 males who arrived in Australia as unaccompanied asylum-seeking minors between 2009 and 2013, and were granted protection visas. The paper focuses on the four conceptual challenges of refugee journeys, as identified recently by BenEzer and Zetter: temporal characteristics; drivers and destinations; the process/content of the journey; and the characteristics of the wayfarers. The findings indicate that their mental journey has not yet ended and transcends the physical departure-arrival voyage. Although the primary drivers for the refugee journey were protection reasons, their desire to find a “better life” free from violence and exclusion also played an important role. The irregular character of the journey made it highly unpredictable, exposed these minors to extreme levels of vulnerability and the need to remain invisible, prompted short lived friendships with other asylum seekers, and created a pervasive feeling of mistrust towards smugglers and other people they met along the way. The study has highlighted the need for interventions to protect unaccompanied minors during their refugee journey.
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In recent decades, the meaning and value of formal state citizenship has shifted dramatically. In the same period, scholarship on citizenship has drawn attention to the proliferation of alternative forms of sub-, supra- and transnational citizenship, at times obscuring the ongoing importance of formal state citizenship. For refugees, however, formal state citizenship remains a critical and widely shared goal. Drawing on interviews with 51 young people from refugee backgrounds in Melbourne, Australia, this article explores the intersecting themes of mobility and security that were identified by participants as the most important benefits of acquiring formal state citizenship in the country of resettlement. In contrast to the insecurity of forced migration, formal state citizenship provides a privileged mobility that enables refugee-background youth to maintain and create transnational identities and attachments and to be protected while doing so, while also granting a secure status within the nation state and insurance against further displacement in an uncertain future. In offering these forms of mobility and security, formal state citizenship contributes to a sense of ontological security among refugee-background youth, providing an important foundation for building national and transnational futures.
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Red light cameras were introduced in Victoria in August 1983, with the intention of reducing the number of accidents that result from motorists disobeying red traffic signals at signalised intersections. Accident data from 46 treated and 46 control sites from 1981 to 1986 were analysed. The analysis indicated that red light camera use resulted in a reduction in the incidence of right angle accidents, and in the number of accident casualties. Legislation was introduced in March 1986 to place the onus for red light camera offences onto the vehicle owner. This legislation was intended to improve Police efficiency and therefore increase the number of red light cameras in operation. Data supplied by the Police indicated that these aims have beneficial road safety effects.
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• In December 1986 funds were approved to double the intensity of random breath testing (RBT) and provide publicity support for police efforts. These changes were considered necessary to make RBT effective. • RBT methods were changed in the metropolitan area to enable block testing (pulling over a block of traffic rather than one or two cars), deployment of police to cut off escape routes, and testing by traffic patrols in all police subdivisions. Additional operators were trained for country RBT. • A publicity campaign was developed, aimed mainly at male drivers aged 18-50. The campaign consisted of the “cardsharp” television commercials, radio commercials, newspaper articles, posters and pamphlets. • Increased testing and the publicity campaigns were launched on 10 April 1987. • Police tests increased by 92.5% in May – December 1987, compared with the same period in the previous four years. • The detection rate for drinking drivers picked up by police who were cutting off escape routes was comparatively high, indicating that drivers were attempting to avoid RBT, and that this police method was effective at detecting these drivers. • A telephone survey indicated that drivers were aware of the messages of the publicity campaign. • The telephone survey also indicated that the target group had been exposed to high levels of RBT, as planned, and that fear of apprehension was the major factor deterring them from drink driving. • A roadside survey of driver blood alcohol concentrations (BACs) by the University of Adelaide’s Road Accident Research Unit (RARU) showed that, between 10p.m. and 3a.m., the proportion of drivers in Adelaide with a BAC greater than or equal to 0/08 decreased by 42%. • Drivers under 21 were identified as a possible problem area. • Fatalities in the twelve month period commencing May 1987 decreased by 18% in comparison with the previous twelve month period, and by 13% in comparison with the average of the previous two twelve month periods (commencing May 1985 and May 1986). There are indications that this trend is continuing. • It is concluded that the increase in RBT, plus publicity, was successful in achieving its aims of reductions in drink driving and accidents.
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Random breath testing (RBT) was introduced in South Australia in 1981 with the intention of reducing the incidence of accidents involving alcohol. In April 1985, a Select Committee of the Upper House which had been established to “review the operation of random breath testing in this State and any other associated matters and report accordingly” presented its report. After consideration of this report, the Government introduced extensive amendments to those sections of the Motor Vehicles Act (MVA) and Road Traffic Act (RTA) which deal with RBT and drink driving penalties. The amended section 47da of the RTA requires that: “(5) The Minister shall cause a report to be prepared within three months after the end of each calendar year on the operation and effectiveness of this section and related sections during that calendar year. (6) The Minister shall, within 12 sitting days after receipt of a report under subsection (5), cause copies of the report to be laid before each House of Parliament.” This is the first such report. Whilst it deals with RBT over a full year, the changed procedures and improved flexibility allowed by the revision to the RTA were only introduced late in 1985 and then only to the extent that the existing resources would allow.
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Review of Stuart Coupe's biography of Australian music legend Michael Gudinski.
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Objective The aim of this study was to gather patients' perceptions regarding their choice between public and private hospital EDs for those who hold private health insurance. The findings of this study will contribute to knowledge regarding patients' decision-making processes and therefore may contribute to the development of evidence based public policies. Methods An in-depth semi-structured guide was used to interview participants at public and private hospital EDs. Questions sought to identify the issues that were considered by the participants to decide to attend that hospital ED, previous ED experience, expectations of ED services and perceived benefits and barriers to accessing services. Interviews were audio recorded, transcribed verbatim and analysed using content and thematic approaches. Results Four core themes emerged: prior good experience with the hospital, perceived quality of care, perceived waiting times and perceived costs that may explain patients' choice. Patients' choice between public and private EDs can be explained by the interaction of these core themes. The principal issues appear to be concern for gap payments at private hospital ED and waiting times at public hospital ED. Conclusions Patients who choose to attend public EDs appear to value financial concern over waiting time; those who choose to attend private EDs appear to value waiting time ahead of financial concerns.
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Aim This study assessed the association between compression use and changes in lymphoedema observed in women with breast cancer-related lymphoedema who completed a 12 week exercise intervention. Methods This work uses data collected from a 12 week exercise trial, whereby women were randomly allocated into either aerobic-based only (n=21) or resistance-based only (n=20) exercise. Compression use during the trial was at the participant’s discretion. Differences in lymphoedema (measured by L-Dex score and inter-limb circumference difference [%]) and associated symptoms between those who wore, and did not wear compression during the 12 week intervention were assessed. We also explored participants’ reasons surrounding compression during exercise. Results No significant interaction effect between time and compression use for lymphoedema was observed. There was no difference between groups over time in the number or severity of lymphoedema symptoms. Irrespective of compression use, there were trends for reductions in the proportion of women reporting severe symptoms, but lymphoedema status did not change. Individual reasons for the use of compression, or lack thereof, varied markedly. Conclusion Our findings demonstrated an absence of a positive or negative effect from compression use during exercise on lymphoedema. Current and previous findings suggest the clinical recommendation that garments must be worn during exercise is questionable, and its application requires an individualised approach.