Book chapters will be unavailable on Saturday 24th August between 8am-12pm BST. This is for essential maintenance which will provide improved performance going forwards. Please accept our apologies for any inconvenience caused.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
After a population of laser-driven hot electrons traverses a limited thickness solid target, these electrons will encounter the rear surface, creating TV/m fields that heavily influence the subsequent hot-electron propagation. Electrons that fail to overcome the electrostatic potential reflux back into the target. Those electrons that do overcome the field will escape the target. Here, using the particle-in-cell (PIC) code EPOCH and particle tracking of a large population of macro-particles, we investigate the refluxing and escaping electron populations, as well as the magnitude, spatial and temporal evolution of the rear surface electrostatic fields. The temperature of both the escaping and refluxing electrons is reduced by 30%–50% when compared to the initial hot-electron temperature as a function of intensity between
. Using particle tracking we conclude that the highest energy internal hot electrons are guaranteed to escape up to a threshold energy, below which only a small fraction are able to escape the target. We also examine the temporal characteristic of energy changes of the refluxing and escaping electrons and show that the majority of the energy change is as a result of the temporally evolving electric field that forms on the rear surface.
The overarching cultural context of the brain injury survivor, particularly that related to minority peoples with a history of colonisation and discrimination, has rarely been referred to in the research literature, despite profoundly influencing a person’s recovery journey in significant ways, including access to services. This study highlights issues faced by Australian Aboriginal traumatic brain injury (TBI) survivors in terms of real-life consequences of the high incidence of TBI in this population, current treatment and long-term challenges.
A case study approach utilised qualitative interview and file review data related to five male Aboriginal TBI survivors diagnosed with acquired communication disorders. The five TBI survivors were from diverse areas of rural and remote Western Australia, aged between 19 and 48 years at the time of injury, with a range of severity.
Common themes included: significant long-term life changes; short-term and long-term dislocation from family and country as medical intervention and rehabilitation were undertaken away from the person’s rural/remote home; family adjustments to the TBI including permanent re-location to a metropolitan area to be with their family member in residential care; challenges related to lack of formal rehabilitation services in rural areas; poor communication channels; poor cultural security of services; and lack of consistent follow-up.
Discussion and Conclusion:
These case reports represent some of the first documented stories of Aboriginal Australian TBI survivors. They supplement available epidemiological data and highlight different contexts for Aboriginal people after TBI, contributing to an overall profile that is relevant for rehabilitation service planning.
The aim of this study was to explore the experiences of radiotherapy students on clinical placement, specifically focussing on the provision of well-being support from clinical supervisors.
Materials and methods:
Twenty-five students from the University of the West of England and City University of London completed an online evaluation survey relating to their experiences of placement, involving Likert scales and open-ended questions.
The quantitative results were generally positive; however, the qualitative findings were mixed. Three themes emerged: (1) provision of information and advice; (2) an open, inclusive and supportive working environment; and (3) a lack of communication, understanding, and consistency.
Students’ experiences on placement differed greatly and appeared to relate to their specific interactions with different members of staff. It is suggested that additional training around providing well-being support to students may be of benefit to clinical supervisors.
Laser–solid interactions are highly suited as a potential source of high energy X-rays for nondestructive imaging. A bright, energetic X-ray pulse can be driven from a small source, making it ideal for high resolution X-ray radiography. By limiting the lateral dimensions of the target we are able to confine the region over which X-rays are produced, enabling imaging with enhanced resolution and contrast. Using constrained targets we demonstrate experimentally a
X-ray source, improving the image quality compared to unconstrained foil targets. Modelling demonstrates that a larger sheath field envelope around the perimeter of the constrained targets increases the proportion of electron current that recirculates through the target, driving a brighter source of X-rays.
A new species, Begonia rheophytica (§ Platycentrum), is described from northern Myanmar; it was initially confused with B. rhoephila, which is confined to Peninsular Malaysia. Comparison with other species with a rheophytic leaf shape is made. This new addition brings the number of currently recognised Begonia species in Myanmar to 73. An updated checklist of Myanmar Begonia species is also included.
Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration.
Despite aspirations to be a world-class national curriculum, the Australian Curriculum (AC) has been criticised as ‘manifestly deficient’ (Australian Government Department of Education and Training, 2014 p. 5) as an inclusive curriculum, failing to meet the needs of all students with disabilities (SWD) and their teachers. There is a need for research into the daily attempts of educators to navigate the tension between a ‘top-down’ system-wide curriculum and a ‘bottom-up’ regard for individual student needs, with a view to informing both policy and practice. This article is the first of two research papers in which we report the findings from a national online Research in Special Education (RISE) Australian Curriculum Survey of special educators in special schools, classes, and units regarding their experience using the AC to plan for and teach SWD. Survey results indicated (a) inconsistent use of the AC as the primary basis for developing learning objectives and designing learning experiences, (b) infrequent use of the achievement standards to support assessment and reporting, and (c) considerable supplementation of the AC from other resources when educating SWD. Overall, participants expressed a lack of confidence in translating the AC framework into a meaningful curriculum for SWD. Implications for policy, practice, and future research are discussed.
It has been shown by Beever, Thomson, Cammell and Harrison (1977) that formaldehyde treatment of silage increased amino acid absorption from the small intestine of sheep by 13% and increased the amount of food protein passing through the rumen undegraded by 66% compared to sheep receiving untreated silage. This paper details the digestion of N and apparent uptake of N, non-ammonia N and amino acid N from the small intestine of Jersey cattle fed a silage made from a second growth, mixed S24 perennial ryegrass/red clover sward which was wilted for 24h and then ensiled either without an additive or with a 50/50 mixture of formic acid and formaldehyde (formalin), each at the rate of 2.2 litres/tonne of grass ensiled. The method of ensiling was by use of an Eberhardt Silopresse (Benedict Agricultural Ltd., London). Each of the three cows fed each diet was equipped with a rumen fistula and re-entrant cannulae into the proximal duodenum and terminal ileum.
The use of silage additives containing lactic acid bacteria and enzymes to promote a rapid homolactic type fermentation has met with some success in the United States but the little evidence available (see Burghardi, Goodrich and Meiske, 1980) suggests that, for grass silages, the value of this type of additive is limited. However, in laboratory silos, inoculation with lactic acid bacteria has been shown to be effective in reducing proteolysis (Carpintero, Henderson and McDonald, 1979).
The recent availability in the UK of a commercial product containing a lactic acid bacteria inoculum and the non-toxicity and ease of application of this product prompted this investigation, which describes the assessment of a silage prepared with this type of additive in comparison with a well characterized additive, formic acid.
Zoonoses are those diseases of animals that can be transmitted to man or vice versa. These may be caused by bacteria, parasites, or more rarely by viruses. This paper will concentrate mainly on the zoonotic bacteria Salmonella spp., Campylobacter spp., E. coli O157 and Yersinia spp. Foodborne disease, often described as food poisoning, is defined as disease due to the consumption of food contaminated with microorganisms or their toxins. In 2000, the most common causes of food poisoning in humans in Great Britain were Campylobacter spp. (60340 cases) and Salmonella spp. (16567 cases). Less than 100 cases of Yersinia spp. infections were reported in humans in England and Wales. Results from surveillance of zoonotic organisms in farm livestock were presented at two conferences organised by MAFF in 2000. The main results are outlined in table 1. It is not possible to guarantee the complete absence from meat of bacteria that can cause infections in people. Thorough cooking of foods should kill all vegetative bacteria. Nevertheless, it is also important that steps are taken throughout the supply chain to minimise the transfer of the bacteria that could cause foodborne disease.
Housed pigs are exposed chronically to aerial pollutants, principally dust and ammonia, at concentrations that may affect performance, possibly by raising the incidence and prevalence of multi-factorial respiratory diseases. Tolerable limits for aerial pollutants are unknown. The aim of this experiment was to test the hypothesis that chronic exposure of weaner pigs to controlled concentrations of aerial dust and ammonia lead to slower growth and lower feed intake compared with controls kept in ‘fresh air’.
Decreases in children's anger reactivity because of the onset of their autonomous use of strategies characterizes the prevailing model of the development of emotion regulation in early childhood (Kopp, 1989). There is, however, limited evidence of the varied pathways that mark this development and their proposed antecedents and consequences. This study used a person-centered approach to identify such pathways, antecedents, and outcomes. A sample of 120 children from economically strained rural and semirural households were observed while waiting to open a gift at ages 24, 36, and 48 months. Multitrajectory modeling of children's anger expressions and strategy use yielded three subgroups. As they aged, typically developing children's strategy use (calm bids and focused distraction) increased while anger expressions decreased. Later developing children, though initially elevated in anger expression and low in strategy use, demonstrated marked growth across indicators and did not differ from typically developing children at 48 months. At-risk children, despite developing calm bidding skills, did not display longitudinal self-distraction increases or anger expression declines. Some predicted antecedents (12–24 month child language skills and language-capitalizing parenting practices) and outcomes (age 5 years externalizing behavior) differentiated pathways. Findings illustrate how indicator-specific departures from typical pathways signal risk for behavior problems and point to pathway-specific intervention opportunities.
To determine the patterns and predictors of treatment response trajectories for veterans with post-traumatic stress disorder (PTSD).
Conditional latent growth mixture modelling was used to identify classes and predictors of class membership. In total, 2686 veterans treated for PTSD between 2002 and 2015 across 14 hospitals in Australia completed the PTSD Checklist at intake, discharge, and 3 and 9 months follow-up. Predictor variables included co-morbid mental health problems, relationship functioning, employment and compensation status.
Five distinct classes were found: those with the most severe PTSD at intake separated into a relatively large class (32.5%) with small change, and a small class (3%) with a large change. Those with slightly less severe PTSD separated into one class comprising 49.9% of the total sample with large change effects, and a second class comprising 7.9% with extremely large treatment effects. The final class (6.7%) with least severe PTSD at intake also showed a large treatment effect. Of the multiple predictor variables, depression and guilt were the only two found to predict differences in response trajectories.
These findings highlight the importance of assessing guilt and depression prior to treatment for PTSD, and for severe cases with co-morbid guilt and depression, considering an approach to trauma-focused therapy that specifically targets guilt and depression-related cognitions.
Asia, a region grappling with the impacts of climate change, increasing natural disasters, and transboundary water issues, faces major challenges to water security. Water resources there are closely tied to the dramatic Hindu-Kush Himalayan (HKH) mountain range, where over 46,000 glaciers hold some of the largest repositories of fresh water on earth (Qiu 2010). Often described as the water tower of Asia, the HKH harbors the snow and ice that form the headwaters of the continent's major rivers (Bandyopadhyay 2013). Downstream, this network of river systems sustains more than 1.3 billion people who depend on these freshwater sources for their consumption and agricultural production, and increasingly as a source of hydropower (Immerzeel, Van Beek, and Bierkens 2010; National Research Council 2012; Rasul 2014).
Contact stress transducers were placed in subglacial bedrock and used to monitor continuously shear stress and normal pressure changes at the contact with the overriding glacier sole 100 m beneath the surface of the Glacier d’Argentière during periods in summer 1973 and spring 1975. The measured fluctuations in normal pressure and shear stress do not appear to be related to changes in sliding velocity. Analysis of the data reveals short-term fluctuations in normal pressure and shear stress which appear to be related to the passage of individual large debris particles or groups of particles over the transducer. The shear stress appears to be a function of the volume concentration of debris in the ice. The volume concentration at any point appears to be partially dependent on a “streaming” process by which basal debris-rich ice tends to flow around the lateral flanks of hummocks on the glacier bed. Where sub-glacial cavities occur, this streaming effect appears to be dependent on the extent of cavitation and thus on ice overburden pressure and velocity. It is suggested that this process can account for an apparent lag between changes in normal pressure and shear stress.
The maximum ratio between shear and normal stress averaged over a period of 10 min was 0.44. This is equivalent to a spatial average over 0.3 cm. Debris concentrations in basal ice of up to 43% by volume occurred. It is suggested that concentrations of this order are common at the base of temperate glaciers and thus that a significant part of the drag at the base of a glacier may be contributed by frictional interactions between the basal-debris load and the bed.