121 resultados para arrival dates


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Determining the temporal scale of biological evolution has traditionally been the preserve of paleontology, with the timing of species originations and major diversifications all being read from the fossil record. However, the ages of the earliest (correctly identified) records will underestimate actual origins due to the incomplete nature of the fossil record and the necessity for lineages to have evolved sufficiently divergent morphologies in order to be distinguished. The possibility of inferring divergence times more accurately has been promoted by the idea that the accumulation of genetic change between modern lineages can be used as a molecular clock (Zuckerkandl and Pauling, 1965). In practice, though, molecular dates have often been so old as to be incongruent even with liberal readings of the fossil record. Prominent examples include inferred diversifications of metazoan phyla hundreds of millions of years before their Cambrian fossil record appearances (e.g., Nei et al., 2001) and a basal split between modern birds (Neoaves) that is almost double the age of their earliest recognizable fossils (e.g., Cooper and Penny, 1997).

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In recent years, a number of phylogenetic methods have been developed for estimating molecular rates and divergence dates under models that relax the molecular clock constraint by allowing rate change throughout the tree. These methods are being used with increasing frequency, but there have been few studies into their accuracy. We tested the accuracy of several relaxed-clock methods (penalized likelihood and Bayesian inference using various models of rate change) using nucleotide sequences simulated on a nine-taxon tree. When the sequences evolved with a constant rate, the methods were able to infer rates accurately, but estimates were more precise when a molecular clock was assumed. When the sequences evolved under a model of autocorrelated rate change, rates were accurately estimated using penalized likelihood and by Bayesian inference using lognormal and exponential models of rate change, while other models did not perform as well. When the sequences evolved under a model of uncorrelated rate change, only Bayesian inference using an exponential rate model performed well. Collectively, the results provide a strong recommendation for using the exponential model of rate change if a conservative approach to divergence time estimation is required. A case study is presented in which we use a simulation-based approach to examine the hypothesis of elevated rates in the Cambrian period, and it is found that these high rate estimates might be an artifact of the rate estimation method. If this bias is present, then the ages of metazoan divergences would be systematically underestimated. The results of this study have implications for studies of molecular rates and divergence dates.

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Studies of molecular evolutionary rates have yielded a wide range of rate estimates for various genes and taxa. Recent studies based on population-level and pedigree data have produced remarkably high estimates of mutation rate, which strongly contrast with substitution rates inferred in phylogenetic (species-level) studies. Using Bayesian analysis with a relaxed-clock model, we estimated rates for three groups of mitochondrial data: avian protein-coding genes, primate protein-coding genes, and primate d-loop sequences. In all three cases, we found a measurable transition between the high, short-term (<1–2 Myr) mutation rate and the low, long-term substitution rate. The relationship between the age of the calibration and the rate of change can be described by a vertically translated exponential decay curve, which may be used for correcting molecular date estimates. The phylogenetic substitution rates in mitochondria are approximately 0.5% per million years for avian protein-coding sequences and 1.5% per million years for primate protein-coding and d-loop sequences. Further analyses showed that purifying selection offers the most convincing explanation for the observed relationship between the estimated rate and the depth of the calibration. We rule out the possibility that it is a spurious result arising from sequence errors, and find it unlikely that the apparent decline in rates over time is caused by mutational saturation. Using a rate curve estimated from the d-loop data, several dates for last common ancestors were calculated: modern humans and Neandertals (354 ka; 222–705 ka), Neandertals (108 ka; 70–156 ka), and modern humans (76 ka; 47–110 ka). If the rate curve for a particular taxonomic group can be accurately estimated, it can be a useful tool for correcting divergence date estimates by taking the rate decay into account. Our results show that it is invalid to extrapolate molecular rates of change across different evolutionary timescales, which has important consequences for studies of populations, domestication, conservation genetics, and human evolution.

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The timing and order of divergences within the genus Rattus have, to date, been quite speculative. In order to address these important issues we sequenced six new whole mitochondrial genomes from wild-caught specimens from four species, Rattus exulans, Rattus praetor, Rattus rattus and Rattus tanezumi. The only rat whole mitochondrial genomes available previously were all from Rattus norvegicus specimens. Our phylogenetic and dating analyses place the deepest divergence within Rattus at ∼3.5 million years ago (Mya). This divergence separates the New Guinean endemic R. praetor lineage from the Asian lineages. Within the Asian/Island Southeast Asian clade R. norvegicus diverged earliest at ∼2.9 Mya. R. exulans and the ancestor of the sister species R. rattus and R. tanezumi subsequently diverged at ∼2.2 Mya, with R. rattus and R. tanezumi separating as recently as ∼0.4 Mya. Our results give both a better resolved species divergence order and diversification dates within Rattus than previous studies.

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The opening phrase of the title is from Charles Darwin’s notebooks (Schweber 1977). It is a double reminder, firstly that mainstream evolutionary theory is not just about describing nature but is particularly looking for mechanisms or ‘causes’, and secondly, that there will usually be several causes affecting any particular outcome. The second part of the title is our concern at the almost universal rejection of the idea that biological mechanisms are sufficient for macroevolutionary changes, thus rejecting a cornerstone of Darwinian evolutionary theory. Our primary aim here is to consider ways of making it easier to develop and to test hypotheses about evolution. Formalizing hypotheses can help generate tests. In an absolute sense, some of the discussion by scientists about evolution is little better than the lack of reasoning used by those advocating intelligent design. Our discussion here is in a Popperian framework where science is defined by that area of study where it is possible, in principle, to find evidence against hypotheses – they are in principle falsifiable. However, with time, the boundaries of science keep expanding. In the past, some aspects of evolution were outside the current boundaries of falsifiable science, but increasingly new techniques and ideas are expanding the boundaries of science and it is appropriate to re-examine some topics. It often appears that over the last few decades there has been an increasingly strong assumption to look first (and only) for a physical cause. This decision is virtually never formally discussed, just an assumption is made that some physical factor ‘drives’ evolution. It is necessary to examine our assumptions much more carefully. What is meant by physical factors ‘driving’ evolution, or what is an ‘explosive radiation’. Our discussion focuses on two of the six mass extinctions, the fifth being events in the Late Cretaceous, and the sixth starting at least 50,000 years ago (and is ongoing). Cretaceous/Tertiary boundary; the rise of birds and mammals. We have had a long-term interest (Cooper and Penny 1997) in designing tests to help evaluate whether the processes of microevolution are sufficient to explain macroevolution. The real challenge is to formulate hypotheses in a testable way. For example the numbers of lineages of birds and mammals that survive from the Cretaceous to the present is one test. Our first estimate was 22 for birds, and current work is tending to increase this value. This still does not consider lineages that survived into the Tertiary, and then went extinct later. Our initial suggestion was probably too narrow in that it lumped four models from Penny and Phillips (2004) into one model. This reduction is too simplistic in that we need to know about survival and ecological and morphological divergences during the Late Cretaceous, and whether Crown groups of avian or mammalian orders may have existed back into the Cretaceous. More recently (Penny and Phillips 2004) we have formalized hypotheses about dinosaurs and pterosaurs, with the prediction that interactions between mammals (and groundfeeding birds) and dinosaurs would be most likely to affect the smallest dinosaurs, and similarly interactions between birds and pterosaurs would particularly affect the smaller pterosaurs. There is now evidence for both classes of interactions, with the smallest dinosaurs and pterosaurs declining first, as predicted. Thus, testable models are now possible. Mass extinction number six: human impacts. On a broad scale, there is a good correlation between time of human arrival, and increased extinctions (Hurles et al. 2003; Martin 2005; Figure 1). However, it is necessary to distinguish different time scales (Penny 2005) and on a finer scale there are still large numbers of possibilities. In Hurles et al. (2003) we mentioned habitat modification (including the use of Geogenes III July 2006 31 fire), introduced plants and animals (including kiore) in addition to direct predation (the ‘overkill’ hypothesis). We need also to consider prey switching that occurs in early human societies, as evidenced by the results of Wragg (1995) on the middens of different ages on Henderson Island in the Pitcairn group. In addition, the presence of human-wary or humanadapted animals will affect the distribution in the subfossil record. A better understanding of human impacts world-wide, in conjunction with pre-scientific knowledge will make it easier to discuss the issues by removing ‘blame’. While continued spontaneous generation was accepted universally, there was the expectation that animals continued to reappear. New Zealand is one of the very best locations in the world to study many of these issues. Apart from the marine fossil record, some human impact events are extremely recent and the remains less disrupted by time.

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Cultural tourism and creative industries have intersecting policy agendas and economic interdependencies. Most studies of the creative industries have focused on western countries. Cultural tourism is rarely included. However the arrival of the creative economy and its movement through developing countries has changed the relationship. Supporters of the creative economy now see fit to include tourism. This thesis addresses the development of the creative economy in Malaysia. The thesis conducted case studies on animation and museum sectors in Malaysia. These two case studies provide information on the development of creative economy in Malaysia. The study found that a top-down cultural management approach is being practised but that Malaysia is now influenced by new ideas concerning innovation and technical creativity. The study examined whether or not technical innovation by itself is enough. The reference points here are the Multimedia Super Corridor in Cyberjaya and other similar projects in the region. The museum case study was situated in Malacca. It showed that museums needed to adapt new media and new experiences to remain relevant in today’s world. In applying a case study approach, the thesis made use of interviews with key stakeholders, as well consulting numerous policy documents and web sites. Both case studies imitated similar products and services in the market but added local characteristics. This research project contributes significantly to the existing body of knowledge in the field of creative economy within the context of developing countries. Finally the thesis makes recommendations for Malaysia to better position itself in the regional economy while retaining its distinctive cultural identity.

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Process-aware information systems, ranging from generic workflow systems to dedicated enterprise information systems, use work-lists to offer so-called work items to users. In real scenarios, users can be confronted with a very large number of work items that stem from multiple cases of different processes. In this jungle of work items, users may find it hard to choose the right item to work on next. The system cannot autonomously decide which is the right work item, since the decision is also dependent on conditions that are somehow outside the system. For instance, what is “best” for an organisation should be mediated with what is “best” for its employees. Current work-list handlers show work items as a simple sorted list and therefore do not provide much decision support for choosing the right work item. Since the work-list handler is the dominant interface between the system and its users, it is worthwhile to provide an intuitive graphical interface that uses contextual information about work items and users to provide suggestions about prioritisation of work items. This paper uses the so-called map metaphor to visualise work items and resources (e.g., users) in a sophisticated manner. Moreover, based on distance notions, the work-list handler can suggest the next work item by considering different perspectives. For example, urgent work items of a type that suits the user may be highlighted. The underlying map and distance notions may be of a geographical nature (e.g., a map of a city or office building), but may also be based on process designs, organisational structures, social networks, due dates, calendars, etc. The framework proposed in this paper is generic and can be applied to any process-aware information system. Moreover, in order to show its practical feasibility, the paper discusses a full-fledged implementation developed in the context of the open-source workflow environment YAWL, together with two real examples stemming from two very different scenarios. The results of an initial usability evaluation of the implementation are also presented, which provide a first indication of the validity of the approach.

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This book examines public worrying over 'ethnic crime' and what it tells us about Australia today. How, for instance, can the blame for a series of brutal group sexual assaults in Sydney be so widely attributed to whole ethnic communities? How is it that the arrival of a foundering boatload of asylum-seekers mostly seeking refuge from despotic regimes in 'the Middle East' can be manipulated to characterise complete cohorts of applicants for refuge 'and their immigrant compatriots' as dangerous, dishonest, criminally inclined and inhuman? How did the airborne terror attacks on the USA on 11 September 2001 exacerbate existing tendencies in Australia to stereotype Arabs and Muslims as backward, inassimilable, without respect for Western laws and values, and complicit with barbarism and terrorism? Bin Laden in the Suburbs argues that we are witnessing the emergence of the 'Arab Other' as the pre-eminent 'folk devil' of our time. This Arab Other functions in the national imaginary to prop up the project of national belonging. It has little to do with the lived experiences of Arab, Middle Eastern or Muslim Australians, and everything to do with a host of social anxieties which overlap in a series of moral panics. Bin Laden in the Suburbs analyses a decisive moment in the history of multiculturalism in Australia. 'Unlike most migrants, the Arab migrant is a subversive will ... They invade our shores, take over our neighbourhood and rape our women. They are all little bin Ladens and they are everywhere: Explicit bin Ladens and closet bin Ladens; Conscious bin Ladens and unconscious bin Ladens; bin Ladens on the beach and bin Ladens in the suburbs, as this book is aptly titled. Within this register ... even a single Arab is a threat. Contain the Arab or exterminate the Arab? A 'tolerable' presence in the suburbs, or caged in a concentration camp? ... The politics of the Western post-colonial state is constantly and dangerously oscillating between these tendencies today. It is this dangerous oscillation that is so lucidly exposed in this book'.

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With the rising popularity of anime amongst animation students, audiences and scholars around the world, it has become increasingly important to critically analyse anime as being more than a ‘limited’ form of animation, and thematically as encompassing more than super robots and pocket monsters. Frames of Anime: Culture and Image-Building charts the development of Japanese animation from its indigenous roots within a native culture, through Japan’s experience of modernity and the impact of the Second World War. This text is the result of a rigorous study that recognises the heterogeneous and polymorphous background of anime. As such, Tze-Yue has adopted an ‘interdisciplinary and transnational’ (p. 7) approach to her enquiry, drawing upon face-to-face interviews, on-site visits and biographical writings of animators. Tze-Yue delineates anime from other forms of animation by linking its visual style to pre-modern Japanese art forms and demonstrating the connection it shares with an indigenous folk system of beliefs. Via the identification of traditional Japanese art forms and their visual connectedness to Japanese animation, Tze-Yue shows that the Japanese were already heavily engaged in what was destined to become anime once technology had enabled its production. Tze-Yue’s efforts to connect traditional Japanese art forms, and their artistic elements, to contemporary anime reveals that the Japanese already had a rich culture of visual storytelling that pre-dates modern animation. She identifies the Japanese form of the magic lantern at the turn of the 19th century, utsushi-e, as the pre-modern ancestor of Japanese animation, describing it as ‘Edo anime’ (p. 43). Along with utsushi-e, the Edo period also saw the woodblock print, ukiyo-e, being produced for the rising middle class (p. 32). Highlighting the ‘resurfacing’ of ‘realist’ approaches to Japanese art in ukiyo-e, Tze-Yue demonstrates the visual connection of ukiyo-e and anime in the …

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Aim: The aim of this pilot study is to describe the use of an Emergency Department (ED) at a large metropolitan teaching hospital by patients who speak English or other languages at home. Methods: All data were retrieved from the Emergency Department Information System (EDIS) of this tertiary teaching hospital in Brisbane. Patients were divided into two groups based on the language spoken at home: patients who speak English only at home (SEO) and patients who do not speak English only or speak other language at home (NSEO). Modes of arrival, length of ED stay and the proportion of hospital admission were compared among the two groups of patients by using SPSS V18 software. Results: A total of 69,494 patients visited this hospital ED in 2009 with 67,727 (97.5%) being in the SEO group and 1,281 (1.80%) in the NSEO group. The proportion of ambulance utilisation in arrival mode was significantly higher among SEO 23,172 (34.2%) than NSEO 397 (31.0%), p <0.05. The NSEO patients had longer length of stay in the ED (M = 337.21, SD = 285.9) compared to SEO patients (M= 290.9, SD = 266.8), with 46.3 minutes (95%CI 62.1, 30.5, p <0.001) difference. The admission to the hospital among NSEO was 402 (31.9%) higher than SEO 17,652 (26.6%), p <0.001. Conclusion: The lower utilisation rates of ambulance services, longer length of ED stay and higher hospital admission rates in NSEO patients compared to SEO patients are consistent with other international studies and may be due to the language barriers.

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Background Many previous studies have found seasonal patterns in birth outcomes, but with little agreement about which season poses the highest risk. Some of the heterogeneity between studies may be explained by a previously unknown bias. The bias occurs in retrospective cohorts which include all births occurring within a fixed start and end date, which means shorter pregnancies are missed at the start of the study, and longer pregnancies are missed at the end. Our objective was to show the potential size of this bias and how to avoid it. Methods To demonstrate the bias we simulated a retrospective birth cohort with no seasonal pattern in gestation and used a range of cohort end dates. As a real example, we used a cohort of 114,063 singleton births in Brisbane between 1 July 2005 and 30 June 2009 and examined the bias when estimating changes in gestation length associated with season (using month of conception) and a seasonal exposure (temperature). We used survival analyses with temperature as a time-dependent variable. Results We found strong artificial seasonal patterns in gestation length by month of conception, which depended on the end date of the study. The bias was avoided when the day and month of the start date was just before the day and month of the end date (regardless of year), so that the longer gestations at the start of the study were balanced by the shorter gestations at the end. After removing the fixed cohort bias there was a noticeable change in the effect of temperature on gestation length. The adjusted hazard ratios were flatter at the extremes of temperature but steeper between 15 and 25°C. Conclusions Studies using retrospective birth cohorts should account for the fixed cohort bias by removing selected births to get unbiased estimates of seasonal health effects.

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Structural health monitoring (SHM) refers to the procedure used to assess the condition of structures so that their performance can be monitored and any damage can be detected early. Early detection of damage and appropriate retrofitting will aid in preventing failure of the structure and save money spent on maintenance or replacement and ensure the structure operates safely and efficiently during its whole intended life. Though visual inspection and other techniques such as vibration based ones are available for SHM of structures such as bridges, the use of acoustic emission (AE) technique is an attractive option and is increasing in use. AE waves are high frequency stress waves generated by rapid release of energy from localised sources within a material, such as crack initiation and growth. AE technique involves recording these waves by means of sensors attached on the surface and then analysing the signals to extract information about the nature of the source. High sensitivity to crack growth, ability to locate source, passive nature (no need to supply energy from outside, but energy from damage source itself is utilised) and possibility to perform real time monitoring (detecting crack as it occurs or grows) are some of the attractive features of AE technique. In spite of these advantages, challenges still exist in using AE technique for monitoring applications, especially in the area of analysis of recorded AE data, as large volumes of data are usually generated during monitoring. The need for effective data analysis can be linked with three main aims of monitoring: (a) accurately locating the source of damage; (b) identifying and discriminating signals from different sources of acoustic emission and (c) quantifying the level of damage of AE source for severity assessment. In AE technique, the location of the emission source is usually calculated using the times of arrival and velocities of the AE signals recorded by a number of sensors. But complications arise as AE waves can travel in a structure in a number of different modes that have different velocities and frequencies. Hence, to accurately locate a source it is necessary to identify the modes recorded by the sensors. This study has proposed and tested the use of time-frequency analysis tools such as short time Fourier transform to identify the modes and the use of the velocities of these modes to achieve very accurate results. Further, this study has explored the possibility of reducing the number of sensors needed for data capture by using the velocities of modes captured by a single sensor for source localization. A major problem in practical use of AE technique is the presence of sources of AE other than crack related, such as rubbing and impacts between different components of a structure. These spurious AE signals often mask the signals from the crack activity; hence discrimination of signals to identify the sources is very important. This work developed a model that uses different signal processing tools such as cross-correlation, magnitude squared coherence and energy distribution in different frequency bands as well as modal analysis (comparing amplitudes of identified modes) for accurately differentiating signals from different simulated AE sources. Quantification tools to assess the severity of the damage sources are highly desirable in practical applications. Though different damage quantification methods have been proposed in AE technique, not all have achieved universal approval or have been approved as suitable for all situations. The b-value analysis, which involves the study of distribution of amplitudes of AE signals, and its modified form (known as improved b-value analysis), was investigated for suitability for damage quantification purposes in ductile materials such as steel. This was found to give encouraging results for analysis of data from laboratory, thereby extending the possibility of its use for real life structures. By addressing these primary issues, it is believed that this thesis has helped improve the effectiveness of AE technique for structural health monitoring of civil infrastructures such as bridges.

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Objective: To evaluate the impact of a government triple zero community awareness campaign on the characteristics of patients attending an ED. Methods: A study using Emergency Department Information System data was conducted in an adult metropolitan tertiary-referral teaching hospital in Brisbane. The three outcomes measured in the 3 month post-campaign period were arrival mode, Australasian Triage Scale and departure status. These measures reflect ambulance usage, clinical urgency and illness severity, respectively. They were compared with those in the 3 month pre-campaign period. Multivariate logistic regression models were used to investigate the impacts of the campaign on each of the three outcome measures after controlling for age, sex, day and time of arrival, and daily minimum temperature. Results: There were 17 920 visits in the pre- and 17 793 visits in the post-campaign period. After the campaign, fewer patients arrived at the ED by road ambulance (odds ratio [OR] 0.90, 95% confidence interval [CI] 0.80–1.00), although the impact of the campaign on the arrival mode was only close to statistical significance (Wald χ2-test, P= 0.055); and patients were significantly less likely to have higher clinical urgency (OR 0.86, 95% CI 0.79–0.94), while more likely to be admitted (OR 1.68, 95% CI 1.38–2.05) or complete treatment in the ED (OR 1.46, 95% CI 1.23–1.73) instead of leaving without waiting to be seen. Conclusions: The campaign had no significant impact on the arrival mode of the patients. After the campaign, the illness acuity of the patients decreased, whereas the illness severity of the patients increased.

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On the 9th April 1955, RAAF Lincoln Bomber A73-64, on a mercy flight to transfer a critically ill infant from Townsville to Brisbane, crashed at Mount Superbus killing the four crew and two civilians on board. The immediate search and rescue was organised by a group of Brisbane bushwalkers who were camping in the area. Police and RAAF personnel subsequently joined the civilians at the crash site to recover the victims. During their initial search of the crash they located what were believed to be the remains of five adults. The arrival of the RAAF Senior Medical Officer (SMO) the following day revealed that only four adult bodies had been found and the bodies of both civilians, an adult and infant, were missing. Later that day the remains of six victims were recovered from the crash site and conveyed to the Warwick Police Station for identification. The RAAF SMO was responsible for the identifications of the aircrew while the Government Medical Officer, police and coroner were responsible for the identifications of the civilians. Eight days later, further remains of the infant were found by a civilian looking through the wreckage. This paper uses archival records not previously researched from a Disaster Victim Identification (DVI) perspective to stimulate interest among forensic practitioners, criminologists and other interested parties in the history of DVI and how practices in Australia have evolved.

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Humanitarian entrants remain invisible in existing populations datasets, and this has significant implications for health care and health policy. We suggest adding 'year of arrival' to population datasets; enabling the combination of 'country of birth' and 'year of arrival' to be used as a proxy for refugee status.