Description:
Climates of the last two millennia have been the focus of numerous studies due to the availability of high-resolution palaeoclimate records and the occurrence of divergent periods of climate, commonly referred to as the 'Medieval Climatic Anomaly' and 'The Little Ice Age'. The majority of these studies are centred in the Northern Hemisphere and, in comparison, the Southern Hemisphere is relatively under-studied. In Australia, there are few high-resolution, palaeoclimate studies spanning a millennium or more and, consequently, knowledge of long-term natural climate variability is limited for much of the continent. South-eastern Australia, which recently experienced a severe, decade-long drought, is one such region.Results are presented of investigations from two crater lakes in the south-east of mainland Australia. Fluctuations in lake-water conductivity, a proxy for effective moisture, are reconstructed at sub-decadal resolution over the past 1500 years using a statistically robust, diatom-conductivity transfer function. These data are interpreted in conjunction with diatom autecology. The records display coherent patterns of change at centennial scale, signifying that both lakes responded to regional-scale climate forcing, though the nature of that response varied between sites due to differing lake morphometry. Both sites provide evidence for a multi-decadal drought, commencing ca 650 AD, and a period of variable climate between ca 850 and 1400 AD. From ca 1400-1880 AD, coincident with the timing of the 'Little Ice Age', climates of the region are characterised by high effective moisture and a marked reduction in inter-decadal variability. The records provide context for climates of the historical period and reveal the potential for more extreme droughts and more variable climate than that experienced since European settlement of the region ca 170 years ago.
Description:
The last 50. years of research into infections in Australia and New Zealand caused by larvae of the sheep blowfly, Lucilia cuprina, have significantly advanced our understanding of this blowfly and its primary host, the sheep. However, apart from some highly effective drugs it could be argued that no new control methodologies have resulted. This review addresses the major areas of sheep blowfly research over this period describing the significant outcomes and analyses, and what is still required to produce new commercial control technologies. The use of drugs against this fly species has been very successful but resistance has developed to almost all current compounds. Integrated pest management is becoming basic to control, especially in the absence of mulesing, and has clearly benefited from computer-aided technologies. Biological control has more challenges but natural and perhaps transformed biopesticides offer possibilities for the future. Experimental vaccines have been developed but require further analysis of antigens and formulations to boost protection. Genetic technologies may provide potential for long-term control through more rapid indirect selection of sheep less prone to flystrike. Finally in the future, genetic analysis of the fly may allow suppression and perhaps eradication of blowfly populations or identification of new and more viable targets for drug and vaccine intervention. Clearly all these areas of research offer potential new controls but commercial development is perhaps inhibited by the success of current chemical insecticides and certainly requires a significant additional injection of resources.
Description:
Objective: Amongst middle-aged men, haplogroup I is associated with approximate to 50% higher risk of coronary artery disease than other paternal lineages of Y chromosome. We hypothesised that carriers of haplogroup I had higher levels of aggression and estrogens and/or lower levels of androgens early in life and thus might be more prone to cardiovascular disease than men with other lineages of Y chromosome. Methods: We reconstructed phylogenetic tree of the Y chromosome in > 1000 young apparently healthy white men from the general population. Each Y chromosome was classified into one of 13 most common European lineages. Androgens (DHEA-S, androstenedione, total testosterone) and their metabolites (total estradiol, estrone) were measured by radioimmunoassays. Information on five dimensions of aggression (total, physical, verbal, anger and hostility) was collected using Buss and Perry questionnaire. Results: Approximately 17% men inherited haplogroup I from their fathers. Carriers of haplogroup I showed lower scores of verbal aggression than men with other haplogroups (beta = -0.72, SE = 0.29, P = 0.012) and when further compared to carriers of most common R1a lineage and other haplogroups (beta = -1.03, SE = 0.34, P = 0.003). However, these associations did not survive a correction for multiple testing. Sex steroids did not show even nominal level of association with haplogroup I. Conclusion: Our data show no overall association between haplogroup I and sex-related phenotypes in young white men. These results also suggest that the previously identified association between haplogroup I and coronary artery disease is not likely mediated by unfavourable profile of sex steroids or heightened aggression early in life. (C) 2014 Elsevier Ireland Ltd. All rights reserved.
Description:
One primary goal of sensor networks is to guarantee robust and accurate event detection while reducing energy consumption for extended lifetime. To increase detection fidelity, recent literature introduces redundancy in the sensor field either by maintaining fixed k-coverage throughout lifetime or by providing dynamic k-coverage using mobile sensors after an event is detected. The former requires a large number of sensor nodes and the latter is costly and sometimes infeasible as mobile node deployment in inaccessible areas is difficult. Exploiting recent advances that allow adjustable sensing and transmission radius for sensors, we propose a scheme that ensures 1-coverage at deployment time, but on detection, extends to k-coverage to increase accuracy and robustness. Using an adjustable sensing model through power adjustment, we formulate an optimization problem that determines the optimal sensor set whose sensing and transmission radius are to be adjusted to provide expected coverage degree, through minimizing a cost function comprising energy consumption and achievable accuracy in detection. For a given sensing adjustability, a guideline for deterministic and random deployment is presented to ensure initial coverage. Detection performance and network lifetime are analyzed both theoretically and through simulation. Our approach avoids over-provisioning in sensor network, increases lifetime and scalability, and maintains detection performance in a cost effective way.
Description:
Flexible operation of post-combustion CO2 capture (PCC) plants can improve efficiency through coordinating the balance between consumer demands for electricity and CO2 emission reductions. This strategy however, will impose process disturbances and the immediate and long term impact is unclear. There is a justified need for the development of accurate dynamic PCC models, as well as practical experience in dynamic operation of PCC pilot plants. This paper presents CSIRO PCC pilot plant data from the 2012 and 2013 dynamic campaigns using MEA solvent. The step-change approach to dynamic plant operation was implemented and the use of density meters to instantaneously measure CO2 loading instantaneously was investigated.
Description:
Flexible operation of post-combustion CO2 capture (PCC) plants can improve efficiency through coordinating the balance between consumer demands for electricity and CO2 emission reductions. This strategy however, will impose process disturbances and the immediate and long term impact is unclear. There is a justified need for the development of accurate dynamic PCC models, as well as practical experience in dynamic operation of PCC pilot plants. This paper presents CSIRO PCC pilot plant data from the 2012 and 2013 dynamic campaigns using MEA solvent. The step-change approach to dynamic plant operation was implemented and the use of density meters to instantaneously measure CO2 loading instantaneously was investigated.
Description:
•Wealth effect of Chinese PE announcements can be seen on application, approval, and completion.•No significant price response on announcements of withdrawal or rejection of applications.•Market discount, proceeds from private placements, and private-institutional buying systematically influence market reaction.•Influence of announcement effect differs across changes in ownership of investor categories.•Results are consistent with the information and ownership structure hypotheses. In response to the China Securities Regulatory Commission's regulation of private equity placements (PEP) in 2006, this study investigates the impact of the announcements of PEP applications, withdrawals, rejections, approvals, and completions on the returns of the firms that issue private equity (PE) and the factors that influence market reactions to these announcements. The results show that issuing firms experience stock price responses only to the announcements of PE applications, approvals, and completions. The announcement effect is positively related to the market discount, proceeds from private placements, and private institutional buying and ownership changes; and negatively related to government or government institutional buying and changes in the ownership of management buyers.
Description:
Understanding the perceptions of stakeholders is critical for determining acceptability and feasibility of volunteer-mediated programs. This study evaluated the feasibility and acceptability for staff, volunteers, patients and their carers, of a volunteer diversional therapy program for patients with cognitive impairment undergoing inpatient rehabilitation. Post-program structured interviews were conducted with the volunteers (n = 10), patients (n = 30) and their carers (n = 3); and nursing staff (n = 6) participated in a focus group. Thematic analysis identified five themes (values, attitudes, knowledge, purpose, support) in two dimensions (personal, team culture). Overall, patients, carers, staff and volunteers were satisfied with the volunteer program and perceived benefits for quality of care. Recommendations for improvements to the program related to staff engagement with the program and the volunteers' education and training. The volunteer diversional therapy pilot program for patients with cognitive impairment on a sub-acute ward was acceptable and feasible for patients, carers, staff and volunteers. (C) 2014 Mosby, Inc. All rights reserved.
Description:
Sensor network localization problem is to determine the position of the sensor nodes in a network given pairwise distance measurements. Such problem can be formulated as a quartic polynomial minimization via the least squares method. This paper presents a canonical duality theory for solving this challenging problem. It is shown that the nonconvex minimization problem can be reformulated as a concave maximization dual problem over a convex set in a symmetrical matrix space, and hence can be solved efficiently by combining a general (linear or quadratic) perturbation technique with existing optimization techniques. Applications are illustrated by solving some relatively large-scale problems. Our results show that the general sensor network localization problem is not NP-hard unless its canonical dual problem has no solution in its positive definite domain. Fundamental ideas for solving general NP-hard problems are discussed. (C) 2014 Elsevier B.V. All rights reserved.
Description:
In this study, a novel and enhanced soil-structure model is developed adopting the direct analysis method using FLAC 2D software to simulate the complex dynamic soil-structure interaction and treat the behaviour of both soil and structure with equal rigour simultaneously. To have a better judgment on the inelastic structural response, three types of mid-rise moment resisting building frames, including 5, 10, and 15 storey buildings are selected in conjunction with three soil types with the shear wave velocities less than 600m/s, representing soil classes Ce, De and Ee, according to Australian Standards. The above mentioned frames have been analysed under two different boundary conditions: (i) fixed-base (no soil-structure interaction) and (ii) flexible-base (considering soil-structure interaction). The results of the analyses in terms of structural displacements and drifts for the above mentioned boundary conditions have been compared and discussed. It is concluded that considering dynamic soil-structure interaction effects in seismic design of moment resisting building frames resting on soil classes De and Ee is essential.
Description:
Objectives: Far fewer injury surveillance systems exist within community sport than elite sport. As a result, most epidemiological data on sports injuries have limited relevance to community-level sporting populations. There is potential for data from community club-based injury surveillance systems to provide a better understanding of community sports injuries. This study aimed to describe the incidence and profile of community-level Australian football injuries reported using a club-based injury surveillance system. Design: Prospective, epidemiological study. Methods: Sports trainers from five community-level Australian football leagues recorded injury data during two football seasons using the club-based system. An online surveillance tool developed by Sports Medicine Australia ('Sports Injury Tracker') was used for data collection. The injury incidence, profile and match injury rate were reported. Results: Injury data for 1205 players were recorded in season one and for 823 players in season two. There was significant variability in injury incidence across clubs. However, aggregated data were consistent across football seasons, with an average of 0.7 injuries per player per season and 38-39 match injuries per 1000. h match exposure. A large proportion of injuries occurred during matches, involved the lower limb and resulted from contact. Conclusions: Data from the club-based system provided a profile of injuries consistent with previous studies in community-level Australian football. Moreover, injury incidence was consistent with other studies using similar personnel to record data. However, injury incidence was lower than that reported in studies using player self-report or healthcare professionals and may be an underestimate of true values.
Description:
The free-volume of a matrix is a fundamental parameter that relates to its molecular and bulk characteristics, such as crystalline change and glass transition behavior. In starch-based bionanocomposite, we investigated the effect of the addition of montmorillonite nanoclay (MMT) and food plasticizers (glycerol and sorbitol) on changes of molecular pore size (including pore volume and pore distribution) using the Positron Annihilation Lifetime Spectroscopy (PALS) method. The results demonstrated counter-intuitive impact of MMT on the total free-volume where the total free-volume increased within the polymeric matrix. When compared to the pure matrix free-volume, the addition of MMT also resulted in the appearance of a broader distribution of the void sizes. The plasticizers, on the other hand, apparently occupied the void spaces, and therefore decreased the free-volume of the matrix. Further, together with the small angle X-ray scattering (SAXS) analysis, we concluded that this is a result of interplay between the plasticizer-plasticizer interactions and the polymer-plasticizer interactions. For example, in the starch/glycerol/MMT system, the pore radii slightly decrease upon the increasing of glycerol amount (OG210 = O.27 nm and OG220 = 0.26 nm), but the relative weight did increase with the increasing glycerol concentration. However, increasing the sorbitol amount increased the pore size from 0.23 nm(OS210) to 0.28 nm(OS220). Furthermore, the addition MMT in the OS010 system, promote the emergence of a new dateable pore radius(0.90 nm), and the total weight significantly increased from 13.70 (OS010) to 19.5% (OS210). We suggest that the pore variation (size and distribution) due to the MMT and plasticizers are reflected in the polymer glass transition and crystallinity because ultimately, the, total free-volume is a reflection of level of interactions existing within the bulk of these nanocomposites.