669 research outputs found
Soils of Seabee Hook, Cape Hallett, northern Victoria Land, Antarctica
The soils of the Seabee Hook area of Cape Hallett in northern Victoria Land, Antarctica, were mapped and characterized. Seabee Hook is a low-lying gravel spit of beach deposits built up by coastal currents carrying basalt material from nearby cliffs. Seabee Hook is the location of an Adélie penguin (Pygoscelis adeliae) colony which influences the soils with additions of guano, dead birds, eggshells and feathers. A soil-landscape model was developed and a soil association was identified between the soils formed on mounds (relict beach ridges) favoured by penguins for nests (Typic Haplorthel) and the soils in the areas between the mounds (Typic Haplorthel/Typic Aquorthel). Soils formed on the mounds inhabited by penguins contained guano in the upper 50 cm, overlying sub-rounded beach-deposited gravel and sand. Soils between mounds had a thin veneer (< 5 cm) of guano overlying basaltic gravelly sand similar to that in the lower parts of the mound soils. The soils had high concentrations of nitrogen, organic carbon, phosphorus, cadmium, zinc, copper, and increased electrical conductivity, within horizons influenced by penguin guano. Five buried penguin bones were collected from the base of soil profiles and radiocarbon dated. The dates indicate that Seabee Hook has been colonized by penguins for at least 1000 years
Transition to adult services for children and young people with palliative care needs: a systematic review.
Objective: To evaluate the evidence on the transition process from child to adult services for young people with palliative care needs.
Design: Systematic review
Setting: Child and adult services and interface between healthcare providers.
Patients: Young people aged 13 to 24 years with palliative care conditions in the process of transition.
Main outcome measures: Young people and their familiesâ experiences of transition, the process of transition between services and its impact on continuity of care, and models of good practice.
Results: 92 studies included. Papers on transition services were of variable quality when applied to palliative care contexts. Most focused on common life threatening and life limiting conditions. No standardised transition programme identified and most guidelines used to develop transition services were not evidence based. Most studies on transition programmes were predominantly condition-specific (e.g. cystic fibrosis, cancer) services. Cystic fibrosis services offered high quality transition with the most robust empirical evaluation. There were differing condition-dependent viewpoints on when transition should occur but agreement on major principles guiding transition planning and probable barriers. There was evidence of poor continuity between child and adult providers with most originating from within child settings.
Conclusions: Palliative care was not, in itself, a useful concept for locating transition-related evidence. It is not possible to evaluate the merits of the various transition models for palliative care contexts, or their effects on continuity of care, as there are no long-term outcome data to measure their effectiveness. Use of validated outcome measures would facilitate research and service development
How to measure response diversity
The insurance effect of biodiversityâthat diversity enhances and stabilises aggregate ecosystem propertiesâis mechanistically underlain by inter- and intraspecific trait variation in organismal responses to environmental change. This variation, termed response diversity, is therefore a potentially critical determinant of ecological stability. However, response diversity has yet to be widely quantified, possibly due to difficulties in its measurement. Even when it has been measured, approaches have varied.Here, we review methods for measuring response diversity and from them distil a methodological framework for quantifying response diversity from experimental and/or observational data, which can be practically applied in lab and field settings across a range of taxa.Previous empirical studies on response diversity most commonly invoke functional response traits as proxies aimed at capturing functional responses to the environment. Our approach, which is based on environment-dependent functional responses to any biotic or abiotic environmental variable, is conceptually simple and robust to any form of environmental response, including nonlinear responses. Given its derivation from empirical data on functional responses, this approach should more directly reflect response diversity than the trait-based approach dominant in the literature.By capturing even subtle inter- or intraspecific variation in environmental responses, and environment-dependencies in response diversity, we hope this framework will motivate tests of the diversity-stability relationship from a new perspective, and provide an approach for mapping, monitoring, and conserving this critical dimension of biodiversity
How to measure response diversity
The insurance effect of biodiversityâthat diversity stabilises aggregate ecosystem propertiesâis mechanistically underlain by interâ and intraspecific trait variation in organismal responses to the environment. This variation, termed response diversity, is therefore a potentially critical determinant of ecological stability. However, response diversity has yet to be widely quantified, possibly due to difficulties in its measurement. Even when it has been measured, approaches have varied.
Here, we review methods for measuring response diversity and from them distil a methodological framework for quantifying response diversity from experimental and/or observational data, which can be practically applied in laboratory and field settings across a range of taxa.
Previous empirical studies on response diversity most commonly invoke response traits as proxies aimed at capturing species' ecological responses to the environment. Our approach, which is based on environmentâdependent ecological responses to any biotic or abiotic environmental variable, is conceptually simple and robust to any form of environmental response, including nonlinear responses. Given its derivation from empirical data on species' ecological responses, this approach should more directly reflect response diversity than the traitâbased approach dominant in the literature.
By capturing even subtle interâ or intraspecific variation in environmental responses, and environment dependencies in response diversity, we hope this framework will motivate tests of the diversityâstability relationship from a new perspective, and provide an approach for mapping, monitoring and conserving this critical dimension of biodiversity
A Land of Plenty? Colonial Diet in Rural New Zealand
Colonial New Zealand was built on the ideal of creating better lives for settlers. Emigrants came looking to escape the shackles of the class-system and poor conditions in Industrial Revolution period Britain. Colonial propaganda claimed that most emigrants achieved their aims, but the lives the colonists actually experienced upon reaching New Zealand remain relatively unexplored from a biosocial perspective. In this paper we present a pilot study of stable isotope results of bone collagen from seven adults interred in the St. Johnâs Cemetery (SJM), Milton, New Zealand (ca. AD 1860â1900). We interpret the diet at Milton and broadly compare our isotopic results with contemporaneous samples from Britain. We show that, like contemporary Britain, the diet of our studied individuals was focused on C3 crops and terrestrial meat sources. Despite higher ????15N values in contemporary UK populations (which can simplistically be interpreted as indicative of higher meat intake), consideration of different local baselines makes it likely that this New Zealand population had relatively similar levels of meat intake. Interestingly marine resources did not form an important part of the Milton diet, despite the site's proximity to the ocean, hinting at the possible stigmatisation of local resources and the development of a European New Zealand (pÄkehÄ) food identity
Loss of Prox1
Correct regulation of troponin and myosin contractile protein gene isoforms is a critical determinant of cardiac and skeletal striated muscle development and function, with misexpression frequently associated with impaired contractility or disease. Here we reveal a novel requirement for Prospero-related homeobox factor 1 (Prox1) during mouse heart development in the direct transcriptional repression of the fast-twitch skeletal muscle genes troponin T3, troponin I2, and myosin light chain 1. A proportion of cardiac-specific Prox1 knockout mice survive beyond birth with hearts characterized by marked overexpression of fast-twitch genes and postnatal development of a fatal dilated cardiomyopathy. Through conditional knockout of Prox1 from skeletal muscle, we demonstrate a conserved requirement for Prox1 in the repression of troponin T3, troponin I2, and myosin light chain 1 between cardiac and slow-twitch skeletal muscle and establish Prox1 ablation as sufficient to cause a switch from a slow- to fast-twitch muscle phenotype. Our study identifies conserved roles for Prox1 between cardiac and skeletal muscle, specifically implicated in slow-twitch fiber-type specification, function, and cardiomyopathic disease
Functional redundancy and sensitivity of fish assemblages in European rivers, lakes and estuarine ecosystems
The impact of species loss on ecosystems functioning depends on the amount of trait similarity
between species, i.e. functional redundancy, but it is also influenced by the order in which species are
lost. Here we investigated redundancy and sensitivity patterns across fish assemblages in lakes, rivers
and estuaries. Several scenarios of species extinction were simulated to determine whether the loss of
vulnerable species (with high propensity of extinction when facing threats) causes a greater functional
alteration than random extinction. Our results indicate that the functional redundancy tended to
increase with species richness in lakes and rivers, but not in estuaries. We demonstrated that i) in the
three systems, some combinations of functional traits are supported by non-redundant species, ii) rare
species in rivers and estuaries support singular functions not shared by dominant species, iii) the loss of
vulnerable species can induce greater functional alteration in rivers than in lakes and estuaries. Overall,
the functional structure of fish assemblages in rivers is weakly buffered against species extinction
because vulnerable species support singular functions. More specifically, a hotspot of functional
sensitivity was highlighted in the Iberian Peninsula, which emphasizes the usefulness of quantitative
criteria to determine conservation prioritiesinfo:eu-repo/semantics/publishedVersio
Ovarian Activity and Oestrous Signs among Group-Housed, Lactating Sows: Influence of Behaviour, Environment and Production
Animal welfare concerns require the development of housing systems that allow the animals to express their natural behaviour. One example of this is the group-housing system for lactating sows. The present study aimed at exploring ovarian activity in such a system. Thirty-eight sows farrowing individually outdoors during spring and summer, and indoors during autumn and winter, and group-housed in groups of four during weeks 3â7 of the lactation period, were monitored regarding reproductive functions, behaviour and production during their first to fourth lactation period. Average ovulation frequency during lactation was 47%. Only 50% of these ovulating cases were accompanied by a standing oestrus. Lactational ovulation frequency was higher in later parities (p < 0.001). Ovulation frequency was higher (p < 0.05) during winter (74%) and spring (69%), than during summer (10%) and autumn (23%). Occurrence of lactational ovulation was associated with some aspects of suckling behaviour and also with litter weight gain (p < 0.05). Forty-nine per cent of the lactational ovulations occurred during the seventh week of lactation. Timing of ovulation seemed positively (p = 0.08) associated with weight loss during lactation. Compared with the sows that were anoestrus during lactation, oestradiol-17ÎČ values were higher (p < 0.05) only in the week before occurrence of lactational ovulation. Weaning-to-oestrous interval was prolonged (p < 0.05) among the sows that ovulated during lactation. The present study identifies several factors influencing ovarian activity among group-housed sows, thereby providing tools for the control of lactational ovulation in group-housing systems
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