Summing the strokes: energy economy in northern elephant seals during large-scale foraging migrations.

BackgroundThe energy requirements of free-ranging marine mammals are challenging to measure due to cryptic and far-ranging feeding habits, but are important to quantify given the potential impacts of high-level predators on ecosystems. Given their large body size and carnivorous lifestyle, we would predict that northern elephant seals (Mirounga angustirostris) have elevated field metabolic rates (FMRs) that require high prey intake rates, especially during pregnancy. Disturbance associated with climate change or human activity is predicted to further elevate energy requirements due to an increase in locomotor costs required to accommodate a reduction in prey or time available to forage. In this study, we determined the FMRs, total energy requirements, and energy budgets of adult, female northern elephant seals. We also examined the impact of increased locomotor costs on foraging success in this species.ResultsBody size, time spent at sea and reproductive status strongly influenced FMR. During the short foraging migration, FMR averaged 90.1 (SE = 1.7) kJ kg(-1)d(-1) - only 36 % greater than predicted basal metabolic rate. During the long migration, when seals were pregnant, FMRs averaged 69.4 (±3.0) kJ kg(-1)d(-1) - values approaching those predicted to be necessary to support basal metabolism in mammals of this size. Low FMRs in pregnant seals were driven by hypometabolism coupled with a positive feedback loop between improving body condition and reduced flipper stroking frequency. In contrast, three additional seals carrying large, non-streamlined instrumentation saw a four-fold increase in energy partitioned toward locomotion, resulting in elevated FMRs and only half the mass gain of normally-swimming study animals.ConclusionsThese results highlight the importance of keeping locomotion costs low for successful foraging in this species. In preparation for lactation and two fasting periods with high demands on energy reserves, migrating elephant seals utilize an economical foraging strategy whereby energy savings from reduced locomotion costs are shuttled towards somatic growth and fetal gestation. Remarkably, the energy requirements of this species, particularly during pregnancy, are 70-80 % lower than expected for mammalian carnivores, approaching or even falling below values predicted to be necessary to support basal metabolism in mammals of this size

The Australian mental health system: An economic overview and some research issues

This article is concerned with the key economic characteristics of Australia's mental health system. First, some brief conceptual and empirical descriptions are provided of Australia's mental health services, both as a total system, and of its two principal components, viz. public psychiatric institutions and private psychiatry services. Expenditures on public psychiatric hospitals clearly demonstrate the effect of deinstitutionalisation. Data from 1984 on private practice psychiatry indicate that per capita utilisation rates peaked in 1996 and have since fallen. Generally, since 1984 gross fees have not risen. However, for both utilisation and fees, there is evidence (of a statistical kind) that there are significant differences between the states of Australia, in these two variables (utilisation and fees). Emphasis is also placed on the economic incentives that arise from health insurance and the heterogeneous nature of mental illness. The effects of these incentives are regarded as by-products of the health insurance mechanism; and another effect, "unmet need" and "met non-need", is a somewhat unique problem of an informational kind. Discussion of many of these issues concludes on a somewhat negative note, e.g. that no empirical results are available to quantify the particular effect that is discussed. This is a manifestation of the lacunae of economic studies of the mental health sector

Analysis of gas chromatography/mass spectrometry data for catalytic lignin depolymerization using positive matrix factorization

Various catalytic technologies are being developed to efficiently convert lignin into renewable chemicals. However, due to its complexity, catalytic lignin depolymerization often generates a wide and complex distribution of product compounds. Gas chromatography/mass spectrometry (GC-MS) is a common analytical technique to profile the compounds that comprise lignin depolymerization products. GC-MS is applied not only to determine the product composition, but also to develop an understanding of the catalytic reaction pathways and of the relationships among catalyst structure, reaction conditions, and the resulting compounds generated. Although a very useful tool, the analysis of lignin depolymerization products with GC-MS is limited by the quality and scope of the available mass spectral libraries and the ability to correlate changes in GC-MS chromatograms to changes in lignin structure, catalyst structure, and other reaction conditions. In this study, the GC-MS data of the depolymerization products generated from organosolv hybrid poplar lignin using a copper-doped porous metal oxide catalyst and a methanol/dimethyl carbonate co-solvent was analyzed by applying a factor analysis technique, positive matrix factorization (PMF). Several different solutions for the PMF model were explored. A 13-factor solution sufficiently explains the chemical changes occurring to lignin depolymerization products as a function of lignin, reaction time, catalyst, and solvent. Overall, seven factors were found to represent aromatic compounds, while one factor was defined by aliphatic compounds

The role of error processing in the contextual interference effect during the training of perceptual-cognitive skills

The contextual interference (CI) effect refers to the learning benefits that occur from a random compared to blocked practice order. In this paper, the cognitive effort explanation for the CI effect was examined by investigating the role of error processing. In two experiments, a perceptual-cognitive task was used in which participants anticipated three different tennis skills across a pre-test, three practice sessions, and retention test. During practice, the skills were presented in either a random or blocked practice order. In Experiment 1, cognitive effort was examined using a probe reaction time task. In Experiment 2, cognitive effort was manipulated for two groups by inserting a cognitively demanding secondary task into the inter-trial interval. The CI effect was found in both experiments as the random groups displayed superior learning in the retention test compared to the blocked groups. Cognitive effort during practice was greater in random compared to blocked practice groups in Experiment 1. In Experiment 2, greater decrements in secondary task performance following an error were reported for the random group when compared to the blocked group. The suggestion is that not only the frequent switching of tasks in randomized orders causes increased cognitive effort and the CI effect, but it is also error processing in combination with task switching. Findings extend the cognitive effort explanation for the CI effect and propose an alternative hypothesis highlighting the role of error processing

An Examination of Middle Bronze Age II Typology and Sequence Dating in Palestine, with Particular Reference to the Tombs of Jericho and Fara (South)

The thesis la concerned with the study of sequence Dating in the MBII tombs of Palestine, particularly those from Jericho and Tell Fara (South). In Chapter One. I have briefly discussed current views on the absolute, chronology of the MBII, more to assess the length of time the period covers than to proscribe its precise dates. In chapter two. I have sought to examine the system of relative chronology in the MBII which Kenyon has proposed for the Jericho tombs. The meaning of typological variation is discussed; Kenyon's chronological arguments are analysed and the application of her technique is shown. In an attempt objectively to test her hypothesis, potential statistical methods are investigated and a selection of suitable deposits is made for experimentation. These deposits are then subjected to a multi-variant trait analysis using multidimensional scaling. The results indicate an insufficient degree of difference in the deposits; they appear to be Virtually indistinguishable from one another. In chapter three. I have republished the MBII tombs from Tell Fara. particularly Petrie’s '500' cemetery in order to investigate the tombs of this period in more detail. I have redrawn all the available objects and attempted to clarity the confusion which surrounds each tomb. Plans, sections and drawings are grouped by tomb by tomb. In the final chapter, I have compared and contrasted Fara with Jericho. At Fara, I certain unique features' of the tombs do not seem to fit readily into the Jericho typological system. It is therefore proposed that such typological change in the MBII may well be a function of local variation rather than of chronological differenc

Siblings, asthma, rhinoconjunctivitis and eczema: a worldwide perspective from the International Study of Asthma and Allergies in Childhood.

BACKGROUND: Associations of larger families with lower prevalences of hay fever, eczema and objective markers of allergic sensitization have been found fairly consistently in affluent countries, but little is known about these relationships in less affluent countries. METHODS: Questionnaire data for 210,200 children aged 6-7 years from 31 countries, and 337,226 children aged 13-14 years from 52 countries, were collected by Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC). Associations of disease symptoms and labels of asthma, rhinoconjunctivitis and eczema were analysed by numbers of total, older and younger siblings, using mixed (multi-level) logistic regression models to adjust for individual covariates and at the centre level for region, language and national affluence. RESULTS: In both age groups, inverse trends (P < 0.0001) were observed for reported 'hay fever ever' and 'eczema ever' with increasing numbers of total siblings, and more specifically older siblings. These inverse associations were significantly (P < 0.005) stronger in more affluent countries. In contrast, symptoms of severe asthma and severe eczema were positively associated (P < 0.0001) with total sibship size in both age groups. These associations with disease severity were largely independent of position within the sibship and national GNI per capita. CONCLUSIONS: These global findings on sibship size and childhood asthma, rhinoconjunctivitis and eczema suggest at least two distinct trends. Inverse associations with older siblings (observations which prompted the 'hygiene hypothesis' for allergic disease) are mainly a phenomenon of more affluent countries, whereas greater severity of symptoms in larger families is globally more widespread

Acoustic Wave Velocity as a Selection Trait in Eucalyptus nitens

Previous studies in Eucalyptus nitens have revealed favourable genetic correlations exist between acoustic wave velocity (AWV) in standing trees and modulus of elasticity (MOE), which can determine the suitability of trees for structural timber and/or engineered wood products. This study investigates the strength and stability of genetic variation in standing tree AWV across a range of environments in Tasmania, where there are a number of large plantation estates and breeding trials. Trees under study were from open-pollinated progeny trials established in 1993. Across sites, for standing tree AWV the ranking of E. nitens races did not change and within-race additive genetic correlations were strong (0.61 to 0.99). Heritabilities (0.16 to 0.74) and coefficients of additive genetic variation (2.6 to 4.8) were moderate for this trait. Correlations between standing tree AWV and both basic density and diameter at breast height (DBH) were favourable. Results indicate that there is potential to improve MOE in E. nitens through the exploitation of genetic variation in AWV among and within races, the expression of genetic variation in AWV is relatively stable across different growing environments, and past selection for basic density and growth in pulpwood breeding programs is unlikely to have adversely affected MOE

Knowing who to trust: Exploring the role of 'ethical metadata' in mediating risk of harm in collaborative genomics research in Africa

Background: The practice of making datasets publicly available for use by the wider scientific community has become firmly integrated in genomic science. One significant gap in literature around data sharing concerns how it impacts on scientists’ ability to preserve values and ethical standards that form an essential component of scientific collaborations. We conducted a qualitative sociological study examining the potential for harm to ethnic groups, and implications of such ethical concerns for data sharing. We focused our empirical work on the MalariaGEN Consortium, one of the first international collaborative genomics research projects in Africa. Methods: We conducted a study in three MalariaGEN project sites in Kenya, the Gambia, and the United Kingdom. The study entailed analysis of project documents and 49 semi-structured interviews with fieldworkers, researchers and ethics committee members. Results: Concerns about how best to address the potential for harm to ethnic groups in MalariaGEN crystallised in discussions about the development of a data sharing policy. Particularly concerning for researchers was how best to manage the sharing of genomic data outside of the original collaboration. Within MalariaGEN, genomic data is accompanied by information about the locations of sample collection, the limitations of consent and ethics approval, and the values and relations that accompanied sample collection. For interviewees, this information and context were of important ethical value in safeguarding against harmful uses of data, but is not customarily shared with secondary data users. This challenged the ability of primary researchers to protect against harmful uses of ‘their’ data. Conclusion: We identified three protective mechanisms – trust, the existence of a shared morality, and detailed contextual understanding – which together might play an important role in preventing the use of genomic data in ways that could harm the ethnic groups included in the study. We suggest that the current practice of sharing of datasets as isolated objects rather than as embedded within a particular scientific culture, without regard for the normative context within which samples were collected, may cause ethical tensions to emerge that could have been prevented or addressed had the ‘ethical metadata’ that accompanies genomic data also been shared. </p

Translating a walking intervention for health professional delivery within primary care: A mixed‐methods treatment fidelity assessment

Objectives: Existing fidelity studies of physical activity interventions are limited in methodological quality and rigour, particularly those delivered by health care providers in clinical settings. The present study aimed to enhance and assess the fidelity of a walking intervention delivered by health care providers within general practice in line with the NIH Behavior Change Consortium treatment fidelity framework. / Design: Two practice nurses and six health care assistants delivered a theory‐based walking intervention to 63 patients in their own practices. A cross‐sectional mixed‐methods study assessed fidelity related to treatment delivery and treatment receipt, from the perspectives of health care providers and patients. / Methods: All providers received training and demonstrated delivery competence prior to the trial. Delivery of intervention content was coded from audio‐recordings using a standardized checklist. Qualitative interviews with 12 patients were conducted to assess patient perspectives of treatment receipt and analysed using framework analysis. / Results: Overall, 78% of intervention components were delivered as per the protocol (range 36–91%), with greater fidelity for components requiring active engagement from patients (e.g., completion of worksheets). The qualitative data highlighted differences in patients’ comprehension of specific intervention components. Understanding of, and engagement with, motivational components aimed at improving self‐efficacy was poorer than for volitional planning components. / Conclusions: High levels of fidelity of delivery were demonstrated. However, patient‐, provider‐, and component‐level factors impacted on treatment delivery and receipt. We recommend that methods for the enhancement and assessment of treatment fidelity are consistently implemented to enhance the rigour of physical activity intervention research