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    Anthropogenic fragmentation may not alter pre-existing patterns of genetic diversity and differentiation in perennial shrubs

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    Many plant species have pollination and seed dispersal systems and evolutionary histories that have produced strong genetic structuring. These genetic patterns may be consistent with expectations following recent anthropogenic fragmentation, making it difficult to detect fragmentation effects if no prefragmentation genetic data are available. We used microsatellite markers to investigate whether severe habitat fragmentation may have affected the structure and diversity of populations of the endangered Australian bird-pollinated shrub Grevillea caleyi R.Br., by comparing current patterns of genetic structure and diversity with those of the closely related G. longifolia R.Br. that has a similar life history but has not experienced anthropogenic fragmentation. Grevillea caleyi and G. longifolia showed similar and substantial population subdivision at all spatial levels (global F\u27 ST = 0.615 and 0.454; S p = 0.039 and 0.066), marked isolation by distance and large heterozygous deficiencies. These characteristics suggest long-term effects of inbreeding in self-compatible species that have poor seed dispersal, limited connectivity via pollen flow and undergo population bottlenecks because of periodic fires. Highly structured allele size distributions, most notably in G. caleyi, imply historical processes of drift and mutation were important in isolated subpopulations. Genetic diversity did not vary with population size but was lower in more isolated populations for both species. Through this comparison, we reject the hypothesis that anthropogenic fragmentation has impacted substantially on the genetic composition or structure of G. caleyi populations. Our results suggest that highly self-compatible species with limited dispersal may be relatively resilient to the genetic changes predicted to follow habitat fragmentation

    Within population variation in germination response to smoke cues: convergent recruitment strategies and different dormancy types

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    Aims: Maintaining variation in germination response provides a selective advantage, by spreading risk during recruitment. In fire-prone regions, physically dormant (PY) species vary their response to dormancy-breaking fire-related heat cues at the intra-population level. However little is known about physiologically dormant (PD) species, which respond to smoke cues. These contrasting dormancy types reflect different evolutionary developmental pathways and we considered whether intra-population variation in germination of Boronia floribunda (PD) occurs in response to smoke. Methods: Seeds were collected from individual plants. We assessed germination magnitude and rate of seeds from each individual in response to a single aerosol smoke treatment, and three concentrations of smoke water, using replicate seed lots in temperature-controlled incubators. Results: The magnitude and onset of germination differed significantly among individuals in response to the same smoke treatment. Seeds from different individuals varied in their sensitivity to smoke water concentration, with some responding to very low doses, and others obligated to high doses. Conclusions: Variation in germination response to smoke highlights a mechanism by which PD species spread risk, by allowing some seeds to emerge quickly, while others remain dormant in the soil seed bank. The similarity to heat-cued variation displayed by PY species suggests that this could represent a convergent functional response

    Educational progress of looked-after children in England: A study using group trajectory analysis

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    2017 by the American Academy of Pediatrics. BACKGROUND: Looked-after children in local authority care are among the most disadvantaged, and measures of their well-being, including educational outcomes, are poorer than other children\u27s. METHODS: The study sample consisted of all children in England born in academic years 1993 to 1994 through 1997 to 1998 who were in local authority care at any point during the academic years 2005 to 2006 through 2012 to 2013 and for whom results of national tests in literacy and numeracy were available at ages 7, 11, and 16 (N = 47 500). RESULTS: Group trajectory analysis of children\u27s educational progress identified 5 trajectory groups: low achievement, late improvement, late decline, predominant, and high achievement. Being looked after earlier was associated with a higher probability of following a high achievement trajectory and a lower probability of following a late decline trajectory. For children first looked after between ages 7 and 16, having a longer total time looked after by age 16 was associated with a higher probability of following a high achievement trajectory. For children with poor outcomes at ages 7 and 11, being looked after by age 16 was associated with an increased chance of educational improvement by age 16. CONCLUSIONS: This study provides evidence that early entry into care can reduce the risk of poor educational outcomes. It also establishes group trajectory analysis as an effective method for analyzing the educational progress of looked-after children, with the particular strength that it allows factors associated with a late decline or improvement in educational progress to be identified

    The university tea room: informal public spaces as ideas incubators

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    Informal spaces encourage the meeting of minds and the sharing of ideas. They serve as an important counterpoint to the formal, silo-like structures of the modern organisation, encouraging social bonds and discussion across departmental lines. We address the role of one such institution – the university tea room – in Australia in the post-WWII decades. Drawing on a series of oral history interviews with economic historians, we examine the nature of the tea room space, demonstrate its effects on research within universities, and analyse the causes and implications of its decline in recent decades

    Effect of body weight support variation on muscle activities during robot assisted gait: a dynamic simulation study

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    Background and Objectives: While body weight support (BWS) intonation is vital during conventional gait training of neurologically challenged subjects, it is important to evaluate its effect during robot assisted gait training. In the present research we have studied the effect of BWS intonation on muscle activities during robotic gait training using dynamic simulations. Methods: Two dimensional (2-D) musculoskeletal model of human gait was developed conjointly with another 2-D model of a robotic orthosis capable of actuating hip, knee and ankle joints simultaneously. The musculoskeletal model consists of eight major muscle groups namely; soleus (SOL), gastrocnemius (GAS), tibialis anterior (TA), hamstrings (HAM), vasti (VAS), gluteus maximus (GLU), uniarticular hip flexors (iliopsoas, IP), and Rectus Femoris (RF). BWS was provided at levels of 0, 20, 40 and 60% during the simulations. In order to obtain a feasible set of muscle activities during subsequent gait cycles, an inverse dynamics algorithm along with a quadratic minimization algorithm was implemented. Results: The dynamic parameters of the robot assisted human gait such as joint angle trajectories, ground contact force (GCF), human limb joint torques and robot induced torques at different levels of BWS were derived. The patterns of muscle activities at variable BWS were derived and analysed. For most part of the gait cycle (GC) the muscle activation patterns are quite similar for all levels of BWS as is apparent from the mean of muscle activities for the complete GC. Conclusions: Effect of BWS variation during robot assisted gait on muscle activities was studied by developing dynamic simulation. It is expected that the proposed dynamic simulation approach will provide important inferences and information about the muscle function variations consequent upon a change in BWS during robot assisted gait. This information shall be quite important while investigating the influence of BWS intonation on neuromuscular parameters of interest during robotic gait training

    Increased Beta Activity Links to Impaired Emotional Control in ADHD Adults With High IQ

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    Objective: The present study investigated the neuropathology of everyday-life executive function (EF) deficits in adults with ADHD with high IQ. Method: Forty adults with ADHD with an IQ ≥ 120 and 40 controls were recruited. Ecological EFs were measured, and eyes-closed Electroencephalograph (EEG) signals were recorded during a resting-state condition; EEG power and correlations with impaired EFs were analyzed. Results: Compared with controls, the ADHD group showed higher scores on all clusters of EF. The ADHD group showed globally increased theta, globally decreased alpha, and increased central beta activity. In the ADHD group, central beta power was significantly related to emotional control ratings, while no such correlation was evident in the control group. Conclusion: The results suggest that resting-state beta activity might be involved in the neuropathology of emotional control in adults with ADHD with high IQ

    Flammability dynamics in the Australian Alps

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    Forests of the Australian Alps (SE Australia) are considered some of the most vulnerable to climate change in the country, with ecosystem collapse considered likely for some due to frequent fire. It is not yet known, however, whether increasing fire frequency may stabilize due to reductions in flammability related to reduced time for fuel accumulation, show no trend, or increase due to positive feedbacks related to vegetation changes. To determine what these trends have been historically, dynamics were measured for 58 years of mapped fire history. The 1.4 million ha forested area was divided into broad formations based on structure and dominant canopy trees, and dynamics were measured for each using flammability ratio, a modification of probability of ignition at a point. Crown fire likelihood was measured for each formation, based on satellite-derived measurements of the 2003 fire effects across a large part of the area. Contrary to popular perception but consistent with mechanistic expectations, all forests exhibited pronounced positive feedbacks. The strongest response was observed in tall, wet forests dominated by Ash-type eucalypts, where, despite a short period of low flammability following fire, post-disturbance stands have been more than eight times as likely to burn than have mature stands. The weakest feedbacks occurred in open forest, although post-disturbance forests were still 1.5 times as likely to burn as mature forests. Apart from low, dry open woodland where there was insufficient data to detect a trend, all forests were most likely to experience crown fire during their period of regeneration. The implications of this are significant for the Alps, as increasing fire frequency has the potential to accelerate by producing an increasingly flammable landscape. These effects may be semi-permanent in tall, wet forest, where frequent fire promotes ecosystem collapse into either the more flammable open forest formation, or to heathland

    Mangrove response to sea level rise: Palaeoecological insights from macrotidal systems in northern Australia

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    Accelerated sea-level rise threatens coastal wetlands; it is unclear whether sediment accretion beneath mangroves will be sufficient to keep pace. A conceptual framework, used to describe the response of reefs, can also be applied to mangroves, discriminating drowning or back-stepping with rapid rise from keep-up or catch-up under moderate rates. In macrotidal estuaries of northern Australia, different mangrove species grow across particular elevation ranges and accretion rates decrease with tidal elevation. Palaeoecological reconstructions, from drilling, dating and pollen analysis, record mangrove distribution over past millennia. Estuarine plains are underlain by a vertically continuous stratigraphy of muds, implying continuity of widespread \u27big swamp\u27 mangrove forests during decelerating stages of post-glacial sea-level rise c. 7000 years ago. In contrast, on higher-energy open coasts, mangroves back-stepped, but re-established as the shoreline prograded when the nearshore built to suitable elevation: a catch-up mode. These results demonstrate that mangrove response to sea-level rise has varied, determined by the availability of sediment and the oceanographic processes by which it is redistributed. How mangrove forests adjust in future will also vary as a function of local topography and sediment availability. Extensive plains flanking estuarine systems are particularly vulnerable to tidal creek extension and saline incursion under future higher sea levels

    Longitudinal qualitative research design: experience over time

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    In this paper I examine time in qualitative researchdesign. I focus on a study design that is almost absent from the literature, inwhich qualitative data are collected repeatedly and prospectively from a cohort of individuals over a long period. I will refer to this design as longitudinal qualitative research, and argue that it carries risks and benefits. It heightens the need for ethical clarity, particularly in respect to repeated participation. Unless the aim is to examine a trajectory of experience, longitudinal design may diminish a study\u27s explanatory power by making the sampling less purposive: commitments to long engagement must be honoured, and the participants selected may, over time, become less informative than expected about the issue under study. Conversely, longitudinal design benefits from the development of a history between the researchers and participants, offers unique access to the actions of, and interactions with, time in the experience under study, and helps to guard against epistemological naiveté on the part of the researcher. Qualitative research isoften blind to time, and I conclude that the greatest contribution of longitudinal qualitative research may be its sensitisation of researchers to the importance of time in social life

    Recent progress on liquid metals and their applications

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    Gallium-based liquid metals show excellent thermal and electrical conductivities with low viscosity and non-toxicity. Their melting points are either lower than or close to room temperature, which endows them with additional advantages in comparison to the solid metals; for example, they are flexible, stretchable and reformable at room temperature. Recently, great improvements have been achieved in developing multifunctional devices by using Ga-based liquid metals, including actuators, flexible circuits, bio-devices and self-healing superconductors. Here, we review recent research progress on Gallium-based liquid metals, especially on the applications aspects. These applications are mainly based on the unique properties of liquid metals, including low melting point, flexible and stretchable mechanical properties, excellent electrical and thermal conductivities and biocompatibility
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