440 research outputs found

    In deep water

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    The Post Qualifying Social Work Part One Programme might be in murky waters, but that doesn't mean 'throwing the baby out with the bath water', as Keith Brown, Natasha Young and Steven Keen explain

    Behavioral Ecology of an Invasive Species: Habitat and Mate Preference(s) in Drosophila Suzukii

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    The invasive Spotted-Wing fruit fly, Drosophila suzukii, has inflicted substantial economic losses to the soft-fruit agriculture industry worldwide due to the ability of females in this species to use a large, serrated ovipositor to cut the fruit’s skin and lay eggs directly into the mesocarp of ripening fruit. Once the eggs hatch, larvae consume the fruit flesh, ultimately leaving the fruit unmarketable. This species parasitizes numerous commercial fruit types (including blueberries, blackberries, strawberries, raspberries and occasionally grapes) as well as fruits from a variety of wild plant species. Since fruit types vary in their nutritional composition, as well as their spatial and temporal availability, this suggests that D. suzukii experiences considerable environmental heterogeneity. The environment can have a large influence on the development and evolution of morphological, physiological, and behavioural phenotypes and, thus, can have significant implications for individual variation and population growth and change over time. Thus to better understand success if this invasive species we have examined the behavioural and developmental and reproductive performance of D. suzukii as it relates to their local environment. Specifically we focused on the role of the nutritional developmental history (NDH), which can either hinder or support offspring growth and survival, and may be an important factor when selecting habitats. Secondly, as the juvenile NDH has the potential to greatly influence adult phenotypes, and consequently individual reproductive potential, we also examined if NDH influenced the operation of sexual selection. Here we report evidence that NDH is an important factor for D. suzukii females when choosing oviposition sites, and can have dramatic consequences for offspring development, mate-choice, offspring fitness, and ultimately population growth. Information on these two subject areas (habitat and mate choice) is of great potential importance to bettering future management strategies (e.g. by manipulating fly numbers based on host preference and reproductive strategies), which are currently limited by lack of knowledge on the biology of this species

    The Economics-Security Nexus in the US-China Trade Conflict decoupling dilemmas

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    For more than two decades, China was enmeshed in transnational trade and investment networks. The complex interdependence that characterised the relationship between the United States and China is now threatened by policies that incentivise decoupling, including the partial unwinding of multinational supply chains. Since 2018 the ‘trade war’ between the US and China has taken on elements of a ‘tech war’, in which national security concerns replace economic logic. The area for win–win gains is reduced, as both countries pursue policies of greater technological autonomy. The bilateral rift creates challenges for companies and third parties who have no wish to take sides and complicates APEC’s goal to promote growth and accelerate regional economic integration

    Walking Through Fire: Black Men’s Quest for Autonomy in August Wilson’s Two Trains Running and King Hedley II

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    This paper explores Black male characters in August Wilson\u27s Two Trains Running and King Hedley II. Characters in these plays seek personal autonomy through economic stability. They seek these things during the turbulent times of the 1960\u27s and 1980\u27s in Pittsburgh, Pennsylvania\u27s Hill District. The roads they take are filled with self discovery, humility and peril

    Interaction of Seed Dispersal and Environmental Filtering Affects Woody Encroachment Patterns in Coastal Grassland

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    Encroachment of woody plants into grasslands has occurred worldwide and includes coastal ecosystems. This conversion process is mediated by seed dispersal patterns, environmental filtering, and biotic interactions. As spatiotemporally heterogeneous, harsh environments, barrier islands present a unique set of challenges for dispersal and establishment. Environmental conditions act as filters on dispersed seeds, thereby influencing encroachment and distribution patterns. Seldom have patterns of propagule dispersal been considered in the context of woody encroachment. We quantified dispersal and post‐dispersal processes of an encroaching woody population of Morella cerifera relative to directional rate of encroachment and observed distribution patterns on an Atlantic coastal barrier island with strong environmental filtering. We analyzed historic foredune elevation as a proxy for reduced interior environmental stress. The dispersal kernel was leptokurtic, a common characteristic of expanding populations, but rate of encroachment has slowed since 2005. Expansion pattern was related to foredune elevation, which limits encroachment below a threshold elevation. This difference between dispersal kernel behavior and encroachment rate is due to limited availability of suitable habitat for Morella and temporal variability in chlorides during the time of germination. Our results demonstrate that processes mediating seeds and seedling success must be accounted for to better understand establishment patterns of encroaching woody plants

    Cognitive Networks Achieve Throughput Scaling of a Homogeneous Network

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    We study two distinct, but overlapping, networks that operate at the same time, space, and frequency. The first network consists of nn randomly distributed \emph{primary users}, which form either an ad hoc network, or an infrastructure-supported ad hoc network with ll additional base stations. The second network consists of mm randomly distributed, ad hoc secondary users or cognitive users. The primary users have priority access to the spectrum and do not need to change their communication protocol in the presence of secondary users. The secondary users, however, need to adjust their protocol based on knowledge about the locations of the primary nodes to bring little loss to the primary network's throughput. By introducing preservation regions around primary receivers and avoidance regions around primary base stations, we propose two modified multihop routing protocols for the cognitive users. Base on percolation theory, we show that when the secondary network is denser than the primary network, both networks can simultaneously achieve the same throughput scaling law as a stand-alone network. Furthermore, the primary network throughput is subject to only a vanishingly fractional loss. Specifically, for the ad hoc and the infrastructure-supported primary models, the primary network achieves sum throughputs of order n1/2n^{1/2} and max⁡{n1/2,l}\max\{n^{1/2},l\}, respectively. For both primary network models, for any ή>0\delta>0, the secondary network can achieve sum throughput of order m1/2−ήm^{1/2-\delta} with an arbitrarily small fraction of outage. Thus, almost all secondary source-destination pairs can communicate at a rate of order m−1/2−ήm^{-1/2-\delta}.Comment: 28 pages, 12 figures, submitted to IEEE Trans. on Information Theor

    Generation of human parallel chimeric antigen receptor (pCAR) T cells to achieve synergistic T cell co-stimulation

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    Dual co-stimulation may be harnessed using parallel chimeric antigen receptors (pCARs) in which two distinct co-stimulatory units are adjacently localized on the plasma membrane. This protocol summarizes construct design, human T cell isolation, retroviral transduction, tissue culture expansion, and preclinical testing of pCAR T cells, exemplified by receptors that co-target avb6 integrin and ErbB dimers. For complete details on the use and execution of this protocol, please refer to Muliaditan et al. (2021)

    Impact of age and race on outcomes of a program to prevent excess weight gain and disordered eating in adolescent girls

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    Interpersonal psychotherapy (IPT) prevents weight gain and reduces loss-of-control (LOC)-eating in adults. However, IPT was not superior to health-education (HE) for preventing excess weight gain and reducing LOC-eating over 1-year in adolescent girls at risk for excess weight gain and eating disorders. Limited data suggest that older and non-White youth may be especially responsive to IPT. In secondary analyses, we examined if age or race moderated weight and LOC-eating outcomes. The 113 participants (12–17 years; 56.6% White) from the original trial were re-contacted 3 years later for assessment. At baseline and follow-up visits through 3 years, we assessed BMI, adiposity by dual energy X-ray absorptiometry, and LOC-eating presence. In linear mixed models, baseline age moderated 3-year BMI outcome; older girls in IPT had the lowest 3-year BMI gain compared to younger girls in IPT and all girls in HE, p = 0.04. A similar pattern was observed for adiposity. Race moderated 3-year LOC-eating; non-White girls in IPT were most likely to abstain from LOC-eating at 3 years compared to all other girls, p = 0.04. This hypothesis-generating analysis suggests future studies should determine if IPT is especially efficacious at reducing LOC-eating in older, non-White adolescents

    Human factors implications of vehicle automation: Current understanding and future directions

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    Advances in vehicle-based technology are currently progressing at an ever- increasing rate and innovations in this area are no longer restricted to Original Equipment Manufacturers or the automotive industry, with service providers such as Google and a number of research institutes in Europe and North America also offering possibilities for new approaches to mobility (see http://www.driverless-future.com/?page_id=155). The race to test the first fleet of such vehicles on public roads is currently underway, with Volvo Cars announcing the start of its Drive Me project by 2017 (Volvo Cars, 2013) and the UK Government recently encouraging cities to engage in demonstrating trials of such vehicles on public roads from January 2015 (BBC, 2014). However, the homogeneous global implementation of fully autonomous vehicles is unlikely in the near to distant future
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