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[Display omitted] • Eocene lamprophyre magmatism is found in South Kalimantan, Borneo. • The lamprophyre has a Priabonian 40Ar/39Ar age of 37.45 ± 0.01 Ma, indistinguishable from the sediments into which it intrudes. • Present day South Kalimantan lithosphere is 50–75% thinner than what is expected for lamprophyre petrogenesis indicating substantial lithospheric thinning since the Priabonian. • Magmatic rocks with well characterised petrogenetic pathways, such as lamprophyres, can be used as paleo-lithospheric thickness indicators. The petrogenetic history of well characterised magmatic rocks may contain invaluable information of paleo-lithospheric thickness and structure that can inform on tectonic evolution. Petrographically distinctive rocks, such as lamprophyres, provide temporal and spatial constraints to build, assess, and verify tectonic models. An alkaline lamprophyre dyke that intrudes the rift-related sediments of the Eocene Tanjung Formation of the Senakin Peninsula in South Kalimantan, Indonesia has been investigated using petrology, whole rock geochemistry and Ar-Ar geochronology. The Senakin lamprophyre dyke is mostly geochemically homogenous but petrographically stratified with vesicle free monchiquite alkaline lamprophyre mineralogy at the base and an amygdale bearing kaersutite phenocryst free upper zone. The major and trace element chemistry is consistent with an intra-plate Ocean Island Basalt like affinity. 40Ar/39Ar dating of hornblende and groundmass aliquots indicates an emplacement age of 37.45 ± 0.10 Ma (2σ), which is consistent with the Late Eocene age of the Tanjung Formation derived from microfossil analysis. The petrology and geochemistry of the Senakin lamprophyre dyke is consistent with magma genesis at > 2GPa beneath a thick lithosphere followed by fractional crystallisation at Moho depths equivalent to 0.5–0.8 GPa. This indicates a much thicker southeastern Kalimantan paleo-lithosphere. Lamprophyre magmatism was initiated by lithospheric extension associated with the opening of the Makassar Strait and also regional thermal upwelling. This extension continued to thin the lithosphere to its current thickness equivalent to 0.5 GPa. [ABSTRACT FROM AUTHOR]

The first 5 years of a child's life are crucial in laying the foundation for their health and developmental trajectory into adulthood. These early years are especially influenced by the surrounding environments in which children live and grow. A large international body of evidence demonstrates that children who experience disadvantage tend to fall increasingly behind over time. At the societal level, these inequities can cause substantial social burdens and significant costs across health, education, and welfare budgets. A contributing factor is that children experiencing adversity are less likely to have access to the environmental conditions that support them to thrive. Many of these factors are modifiable at the community or place level. We argue for three key—though not exhaustive—ideas that collectively could achieve more equitable outcomes for children facing disadvantage and experiencing adversity: 1. Adopt a social determinants approach to conceptualizing disadvantage; 2. Stack existing, evidence-based government and nongovernment service interventions/programs that operate at the local or community level; and 3. Use data and evidence to focus improvements for more equitable and adaptive systems. We conclude that if adopted, these 3 ideas could contribute to the ability of local communities and networks to identify and respond to factors that address early childhood inequalities. [ABSTRACT FROM AUTHOR]

Nutrient availability is an important control on the vegetation distribution, productivity and functioning of peatland ecosystems and we examined spatial and temporal patterns of nutrient availability through ion exchange at Mer Bleue bog, southeast Ontario, Canada. We installed ion exchange probes at 5–15 cm for 4 weeks and determined nutrient sorption at undisturbed sites as well as those affected by nitrogen (N), phosphorus (P), potassium (K) fertilization and drainage. Under undisturbed conditions, the bog had very small amount of available nutrients, especially N (ammonium > nitrate) and P, and exhibited small variations in nutrient availability during the growing season (May to October). The increase in NPK availability upon fertilization was short-lived over the season and the stoichiometry of available NPK captured by the probes was mismatched with the vegetation. The increase in nutrient availability with drainage was confounded by substantial changes in vegetation. We compare these results with data from other Canadian bogs and fens to provide baseline data on nutrient availability in peatlands. [ABSTRACT FROM AUTHOR]

Both historical and contemporary residential care for children have been found to present risks to their safety and security. Views about the characteristics of workers that helped them to feel safe in the placement were obtained from 27 children and young people who were placed in residential care in Australia. Competent and trustworthy staff were considered essential. These workers were characterised as caring, proactive, tenacious in building relationships, and available. Importantly, they listened and ensured young people had a voice. The study affirms the central role of the worker-client alliance in ensuring residential care is a positive and safe experience for children and young people, and identifies structural factors that children and young people believe are barriers to them feeling safe. [ABSTRACT FROM AUTHOR]

The Australian Royal Commission into Institutional Responses to Child Sexual Abuse has set in motion a number of systemic and organizational approaches to identify and respond to child sexual abuse. These include increased child abuse awareness, developing and enhancing child-safe organizational cultures and policies and more thorough screening and supervision of staff in child and youth serving organizations. Although these advances should be applauded, many of the concerns that children and young people have raised about interpersonal safety have not been fully addressed. There is therefore a risk that children’s physical, relational, generational, and organizational powerlessness are reinforced through child-safe practices that restrict their meaningful participation, ignore their agency and capacity and fail to respond to their felt safety needs or wishes. This paper presents the findings of a qualitative research project conducted with 121 Australian children and young people and presents their perspectives on issues of vulnerability and the ways that they would like adults and institutions to respond to their safety concerns. The value of adult-child alliances, of formal mechanisms that are child-friendly and accessible and having external agencies monitor and review institutional strategies to preventing harm are discussed. [ABSTRACT FROM AUTHOR]

While considerable attention has been given to the measurement of mercury (Hg) and lead (Pb) concentrations and accumulation in detailed peat cores in central Canada, the geographic distribution and density of sampling are generally limited. Here, we use the Ontario Peatland Inventory to examine broad patterns of Hg and Pb concentration with depth, based on 338 peat cores (containing >1500 analyzed samples) from 127 bogs, fens and swamps located in southeastern, northeastern and northwestern sections of Ontario. Overall, Hg concentrations averaged 0.05 μg g −1 and that of Pb averaged 10.8 μg g −1 . Maximum values in the top 50 cm of the profiles are 0.08 μg g −1 and 26.2 μg g −1 for Hg and Pb, respectively. The ratio between these values (surface) and the values from below 100 cm (background), where peat likely accumulated before 1850 and industrial activities were limited, are 2.3 and 6.6 for Hg and Pb, respectively. The highest surface:background concentration ratios are generally found in the westernmost part of the province and in the southeast for Hg and around areas that are more heavily populated for Pb. Our results show that a vast amount of Hg and Pb are stored in Ontarian peatlands, although the spatial distribution of these stores varies. The rapid decomposition of peat in a changing climate could release these pollutants to the atmosphere. [ABSTRACT FROM AUTHOR]

Young people who live in residential care are at greater risk of experiencing sexual abuse and other forms of abuse than those living in other out of home care placements. To better understand how young people perceive and experience safety in residential care, and the things that they most need to be and feel safe, a qualitative study was conducted with 27 Australian children and young people for the Royal Commission into Institutional Responses to Child Sexual Abuse. This paper describes young people's perspectives on what makes residential care safe: supportive relationships, stability and predictability, fair rules, and having some control over their environment. Young people said that safety could be improved with: better appreciation of the risks in residential care; better matching, staffing and oversight; and better-designed responses that involve young people themselves. The findings provide critical insights from young people themselves and argue that adults and institutions need to appreciate their views of safety so as to adequately respond. [ABSTRACT FROM AUTHOR]

• Parenting aspirations of young people who have experienced adversity are overlooked. • Young people would like to be parents but had other goals to achieve first. • Goals included addressing enjoying their youth, addressing personal difficulties. • Aspirations were influence by childhood experiences and current circumstances. Only a limited number of studies have sought to examine the parenting attitudes and aspirations of young people who have experienced abuse, neglect, and childhood adversity and who are not yet pregnant or parenting. Given the dearth of literature on this topic, this study explores the attitudes and aspirations relating to pregnancy and parenthood among South Australian young people who have experienced abuse, neglect, or childhood adversity. A total of fifteen young people (8 male and 7 female) were recruited from a variety of services that may be serving young people with experiences of abuse, neglect, or early adversity. Young people took part in a semi-structured interview exploring their attitudes and aspirations regarding relationships, pregnancy, and parenthood. Young people discussed whether they would like to be parents, and some of the goals and aspirations that they would like to achieve beforehand. The reasons why young people wanted to be parents later in life and achieve these goals first were categories into three interrelated groups: they wanted to enjoy their youth and succeed in education or employment, they wanted to address their own personal difficulties and challenges first or they wanted to be prepared and be in the best position possible to meet the needs of their future children. While most of the sample were not planning on becoming parents before they turned 25, all aspired to have children at some point. Young people's aspirations towards younger parenthood were varied and often shaped by their childhood experiences and current circumstances. Implications for policy and practice are discussed. [ABSTRACT FROM AUTHOR]

The large accumulation of carbon in peatlands arises from slow organic matter decomposition where microorganisms and their enzyme activities play a critical role. However, there is a dearth of studies on the natural patterns of peatland microbial enzyme activity and inhibitory phenolic compounds over seasons, and across a range of depths and biogeochemically different peatland types. We report the spatiotemporal patterns for phenol oxidases, phenolics, and a suite of five key hydrolase enzymes at two depths in two ombrotrophic bogs, mineral poor and rich fens, and a forested basin swamp over the growing season. Results obtained using linear fixed and mixed effect models suggest that phenol oxidase activity varies significantly with temperature and, to a lesser extent pH, leading to a breakdown of inhibitory phenolics and increased hydrolase enzyme activity across all peatland types. Overall, enzyme activity decreased significantly with depth and showed significant variation over the course of the growing season with a minimum in the spring and a maximum in the summer and fall. Enzyme activities were generally greatest in the rich fen and lowest in the forested basin swamp with no significant difference between bogs and poor fens. Site-specific factors such as nutrient availability explain deviations from these patterns. Our results illustrate the widespread but conditional applicability of the enzyme-latch mechanism to peatlands and the vulnerability of the peatland soil organic carbon stock to climate warming. [ABSTRACT FROM AUTHOR]

The link between early school leaving and criminal behaviour has been well established within the literature. However, little is known about how young people understand and experience difficulties at school, reflect on their problem behaviours and ways that the broad welfare and education systems might better support them. This article reports on a qualitative research project conducted with young people engaged in the youth justice system in the Australian Capital Territory, in which participants reflected on their lives and the factors that led to their early school leaving and criminality. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: This paper presents a synthesis of experiments conducted in a tropical tree plantation established in 2001 and consisting of 22 plots of 45m×45m with either one, three or six native tree species. We examined the changes in carbon (C) pools (trees, herbaceous vegetation, litter, coarse woody debris (CWD), and mineral topsoil at 0–10cm depth) and fluxes (decomposition of CWD and litter, as well as soil respiration) both through time and among diversity levels. Between 2001 and 2009 the aboveground C pools increased, driven by trees. Across diversity levels, the mean observed aboveground C pool was 7.9±2.5Mgha−1 in 2006 and 20.4±7.4Mgha−1 in 2009, a 158% increase. There was no significant diversity effect on the observed aboveground C pool, but we found a significant decrease in the topsoil C pool, with a mean value of 34.5±2.4Mgha−1 in 2001 and of 25.7±5.7Mgha−1 in 2009 (F 1,36 =52.12, p <0.001). Assuming that the biomass C pool in 2001 was negligible (<1Mgha−1), then the plantation gained in C, on average, ∼20 and lost ∼9Mgha−1 in biomass and soil respectively, for an overall gain of ∼11Mgha−1 over 8 years. Across the entire data set, we uncovered significant effects of diversity on CWD decomposition (diversity: F 2,393 =15.93, p <0.001) and soil respiration (monocultures vs mixtures: t =15.35, df=11, p <0.05) and a marginally significant time×diversity interaction on the loss of total C from the mineral topsoil pool (see above). Monthly CWD decomposition was significantly faster in monocultures (35.0±24.1%) compared with triplets (31.3±21.0%) and six-species mixtures (31.9±26.8%), while soil respiration was higher in monocultures than in mixtures (t =15.35, df=11, p <0.001). Path analyses showed that, as diversity increases, the links among the C pools and fluxes strengthen significantly. Our results demonstrate that tree diversity influences the processes governing the changes in C pools and fluxes following establishment of a tree plantation on a former pasture. We conclude that the choice of tree mixtures for afforestation in the tropics can have a marked influence on C pools and dynamics. [Copyright &y& Elsevier]

Abstract: Biodegradable polyurethanes are typically prepared from polyester polyols, aliphatic diisocyanates and chain extenders. We have developed a degradable chain extender (DCE) based on dl-lactic acid and ethylene glycol to accelerate hard segment degradation. Three series of polyurethane elastomers were synthesised to investigate the effect of incorporating DCE on synthesis, mechanical and thermal properties and in-vitro degradation. Polyurethane soft segments were based on poly(ε-caprolactone) (PCL) polyol. The hard segment was based on either ethyl lysine diisocyanate or hexamethylene diisocyanate in combination with ethylene glycol or DCE. Polyurethanes were characterised by gel permeation chromatography, tensile testing (Instron) and differential scanning calorimetry. Polymer degradation in-vitro (phosphate buffered saline) was tested by measuring mass loss, change in molecular weight and amine concentration in degradation products at three different time points over a 1 year period. Incorporation of DCE did not affect thermal or mechanical properties but had an influence on the in-vitro degradation. All polyurethanes exhibited considerable molecular weight decrease over the test period, and DCE-based polyurethanes showed the highest mass loss. The presence of the DCE and the initial molecular weight of the polyurethane are the key factors responsible for high mass losses. Differential scanning calorimetry, amine group analysis and the observation that mass loss was directly proportional to hard segment weight percentage, strongly supported that the polyurethane hard segment is the most susceptible segment to degradation in these polyurethanes. The PCL-based soft segment appears to undergo little or no degradation under these test conditions. [Copyright &y& Elsevier]

Abstract: Recent advances in the synthesis of poly(γ-butyrolactone) have yielded homopolymers of up to 50,000Mw from the low-cost monomer γ-butyrolactone. This monomer has for the better part of a century been thought impossible to polymerise. Poly(γ-butyrolactone) displays properties that are ideal for tissue-engineering applications and the bacterially derived equivalent, poly(4-hydroxybutyrate) (P4HB), has been evaluated for such uses. The glass transition temperature (-48 to -51°C), melting point (53–60°C), tensile strength (50MPa), Young''s modulus (70MPa) and elongation at break (1000%) of P4HB make it a very useful biomaterial. Poly(γ-butyrolactone) degrades to give γ-hydroxybutyric acid which is a naturally occurring metabolite in the body and it has been shown to be bioresorbable. Investigation into the synthesis of poly(γ-butyrolactone) has recently produced homo-oligomeric diols 400–1000Mw that are suitable for reacting with diisocyanates to form polyurethanes. Biodegradable polyurethanes made from diols of polyglycolide (PGA) and poly(ɛ-caprolactone) (PCL) have the disadvantage of high glass transition and slow degradation, respectively. Poly(γ-butyrolactone) can be thought of as being the missing link in the biodegradable polyester family immediately between PGA and PCL and displaying intermediate properties. [Copyright &y& Elsevier]

Abstract: A challenge for many EAP teachers working on pre-sessional programs is to find ways to reconcile the dual aims of preparing students for university study and for the IELTS test. The study described here seeks to provide some guidance on this issue through an analysis of the type of writing required in the two domains. We compared the standard IELTS Task 2 rubric with a corpus of 155 assignment tasks collected at two Australian universities and found that whilst IELTS writing bears some resemblance to the predominant genre of university study-the essay, there are also some very important difference. Our findings suggest that the type of writing the test elicits may have more in common with certain public nonacademic genres, and thus should not be thought of as an appropriate model for university writing. We conclude that it is probably best to deal with test preparation and the broader EAP writing curriculum within separate programs. [Copyright &y& Elsevier]

We used a phytoestrogen (PE) and a phytoestrogen-free (PE-Free) diet to determine whether or not diet can have neurobehavioral effects on intermale aggression in Syrian hamsters (Mesocricetus auratus). In Experiment 1, 20 adult male hamsters were pre-tested for aggression and then placed on a PE (n=10) or a PE-Free diet (n=10) for 4 weeks in isolation. During week 5, experimental hamsters were exposed to a group-housed, nonaggressive opponent (NAO) for 5 min in a neutral cage arena. PE-fed hamsters exhibited more attacks (33.4±6.1) toward the NAO compared to the PE-Free-fed hamsters (18.1±4) (p<0.05). Interestingly, testosterone in the blood serum was higher in the PE-fed group (11.01±1.48 ng/ml) compared to the PE-Free group (6.5±0.87 ng/ml). In Experiment 2, 16 juvenile hamsters were weaned onto a PE (n=8) or a PE-Free diet (n=8). After 7 weeks on the diet, experimental hamsters were exposed to a NAO for 5 min in a neutral cage arena. Although the PE group exhibited higher levels of aggressive behavior, there were no statistically significant differences between groups. However, the PE group had higher levels of testosterone (9.0±0.95 ng/ml) compared to the PE-Free group (4.6±0.98 ng/ml) (p<0.05). In addition, analysis of the brains from both experiments revealed differences in binding for vasopressin 1A (V1A) receptors. Optical densities were converted to disintegrating units per min/mg. The PE-Free group had higher levels of V1A receptor binding (2689.93±254.8 dpm/mg) compared to the PE group (1907.32±136.3 dpm/mg) in the lateral septum (p<0.05). In addition, there were differences in the lateral hypothalamus, but the PE group had higher receptor binding (2550.9±63.59 dpm/mg) when compared to the PE-Free group (2011.9±174.14 dpm/mg) (p<0.05). In sum, these data present the first evidence that phytoestrogens can affect aggressive behavior and, concurrently, alter hormonal status and stimulate changes in the brain of male hamsters. [Copyright &y& Elsevier]

We investigated the response of CO2 and CH4 production to a water table fluctuation and a SO42− pulse in a bog mesocosm. Net gas production rates in the mesocosm were calculated from concentration data by diffusive mass-balances. Incubation experiments were used to quantify the effect of SO42− addition and the distribution of potential CO2 and CH4 production rates. Flooding of unsaturated peat resulted in rapid depletion of O2 and complex patterns of net CH4, CO2, and H2S production. Methane production began locally and without a time lag at rates of 3–4 nmol cm−3 d−1 deeper in the peat. Similar rates were determined after a time lag of 10–60 days in the surface layers, whereas rates at lower depths declined. Net CO2 production was largest immediately after the water table position was altered (100–300 nmol cm−3 d−1) and declined to −50–50 nmol cm−3 d−1 after a few weeks. SO42− addition (500 mM) significantly increased potential CH4 production rates in the surface layer from an average of 132–201 nmol cm−3 d−1 and reduced it below from an average of 418–256 nmol cm−3 d−1. Our results suggest that deeper in the peat (40–70 cm) under in situ conditions, methanogenic populations are less impaired by unsaturated conditions than in the surface layers, and that at these depths after flooding the substrate availability for CH4 and DIC production is significantly enhanced. They also suggest that methanogenic and SO42−-reducing activity were non-competitive in the surface layer, which might explain contradictory findings from field studies. [Copyright &y& Elsevier]

Copyright of Forest Ecology & Management is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper investigates variation in knowledge construction in three disciplines—sociology, economics and physics—by drawing on Halliday''s notion of “metaphenomenon”. Specifically, the study analysed the frequency and type of agentive elements (participants and processes) in textbooks to find out the extent to which knowledge in these disciplines is attributed to individual scholars, schools of thought, conventional wisdoms and the like, as opposed to being realised in a non-attributed canonical form. The findings suggest that with respect to the feature of metaphenomenon, economics textbook discourse is arguably more akin to that of physics than its social science counterpart, sociology. The implications of the findings—both pedagogical and ideological—are discussed. [Copyright &y& Elsevier]

When conducted in tandem, organic petrography and isotopic analyses can be used to interpret regional tectonics and palaeoclimate within a global context. As an example, a sequence of lignite (vitrinite reflectance average = 0.27%) in the Lower Cretaceous Yimin Formation, Inner Mongolia, China, was investigated. The study area is within the intracratonic Hailar Basin and was situated at ~45°N palaeolatitude. Globally warm temperatures allowed temperate to tropical vegetation such as ferns, cycads and gymnosperms to form thick, laterally extensive palaeomires within the basin. Probabilistic assessment indicates that the lower, thick (~40 m) Seam #16 may have accumulated over a time span between 174 (P10) to 481 (P90) thousand years, whereas the thin (~6 m) overlying Seam #16 Upper took between 20 (P10) and 96 (P90) thousand years. Thermal sag processes were active in the basin during these time periods, with subsidence rates balanced to allow enough accommodation space to accumulate thick peat, but not so fast as to induce flooding and burial by clastics. A high proportion of fossil charcoal ('inertinite') in both seams indicate that throughout the peat-forming period, fire was an important part of the mire ecology. This is consistent with global high oxygen content and an in-land continental palaeogeographic position with seasonal precipitation. Stable isotopes of carbon indicate periods of high precipitation but also times of significant relative dryness. The palaeoclimatic conditions are likely to be both seasonal as well as longer term, possibly decadal to millennium in scale and would have occurred over the whole region, not just mire specific. Image 1 • In-land Laurasia during the Early Cretaceous was highly susceptible to fire, possibly a result of higher atmospheric oxygen content. • Carbon isotopes indicate the region experienced dry periods, which facilitate degradation of the charcoal (inertinite). • The region was tectonically active allowing accommodation space for thick peats to accumulate. • The initiation and the termination of mire systems were at the mercy of subsidence rates. • Although during a time of angiosperm radiation, they were not yet an integral part of mire eco-systems. [ABSTRACT FROM AUTHOR]

Hydrological disturbances can alter the structure and function of ecosystems by changing plant species composition over time. Peatlands in the northern hemisphere are particularly sensitive to global change drivers related to soil water availability, such as drought and drainage, because of important ecohydrological feedbacks between species composition and water table position. Here, we examined the plant community structure and environmental drivers of species distributions over two growing seasons along a bog – margin gradient, pre- and post-disturbance by beaver activity. Pond drainage resulted in seasonal average water table depth 8–24 cm lower in the second season. Five plant communities corresponded to changes in water table depth and acidity: bog, poor fen, meadow, mudflat and pond. Plant cover increased in meadow and mudflat communities, decreased in the pond community and did not differ between years in bog and poor fen communities. Changes in species abundance between years showed signs of alternate successional pathways: one that favors Sphagnum moss and bog community expansion and another pathway that favors meadow and mudflat expansion. This study highlights the non-linear successional trajectory of plant communities with changes in water table depth, which has implications for land management goals that aim to conserve the ecological integrity of peatland ecosystems. [ABSTRACT FROM AUTHOR]

Pools are common in northern peatlands but studies have seldom focused on their nutrient biogeochemistry, especially in relation to their morphological characteristics and through seasons. We determined the environmental characteristics controlling carbon (C), nitrogen (N) and phosphorus (P) biogeochemistry in pools and assessed their evolution over the course of the 2016 growing season in a subboreal ombrotrophic peatland of eastern Canada. We showed that water chemistry variations in 62 pools were significantly explained by depth (81.9%) and the surrounding vegetation type (14.8%), but not by pool area or shape. Shallow pools had larger dissolved organic carbon (DOC) and total nitrogen (TN) concentrations and lower pH than deep pools, while pools surrounded by coniferous trees had more recalcitrant DOC than pools where vegetation was dominated by mosses. The influence of depth on pool biogeochemistry was confirmed by the seasonal survey of pools of different sizes with 47.1% of the variation in pool water chemistry over time significantly explained. Of this, 67.3% was explained by the interaction between time and pool size and 32.7% by pool size alone. P concentrations were small in all pools all summer long and combined with high N:P ratios, are indicative of P-limitation. Our results show that pool biogeochemistry is influenced by internal processes and highlight the spatial and temporal heterogeneity of nutrient biogeochemistry in ombrotrophic peatlands. [ABSTRACT FROM AUTHOR]