2,532 research outputs found

    Hydro-Responsive Curling of the Resurrection Plant Selaginella lepidophylla

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    The spirally arranged stems of the spikemoss Selaginella lepidophylla, an ancient resurrection plant, compactly curl into a nest-ball shape upon dehydration. Due to its spiral phyllotaxy, older outer stems on the plant interlace and envelope the younger inner stems forming the plant centre. Stem curling is a morphological mechanism that limits photoinhibitory and thermal damages the plant might experience in arid environments. Here, we investigate the distinct conformational changes of outer and inner stems of S. lepidophylla triggered by dehydration. Outer stems bend into circular rings in a relatively short period of desiccation, whereas inner stems curl slowly into spirals due to hydro-actuated strain gradient along their length. This arrangement eases both the tight packing of the plant during desiccation and its fast opening upon rehydration. The insights gained from this work shed light on the hydro-responsive movements in plants and might contribute to the development of deployable structures with remarkable shape transformations in response to environmental stimuli

    Evidence-based planning and costing palliative care services for children : novel multi-method epidemiological and economic exemplar

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    Background: Children’s palliative care is a relatively new clinical specialty. Its nature is multi-dimensional and its delivery necessarily multi-professional. Numerous diverse public and not-for-profit organisations typically provide services and support. Because services are not centrally coordinated, they are provided in a manner that is inconsistent and incoherent. Since the first children’s hospice opened in 1982, the epidemiology of life-limiting conditions has changed with more children living longer, and many requiring transfer to adult services. Very little is known about the number of children living within any given geographical locality, costs of care, or experiences of children with ongoing palliative care needs and their families. We integrated evidence, and undertook and used novel methodological epidemiological work to develop the first evidence-based and costed commissioning exemplar. Methods: Multi-method epidemiological and economic exemplar from a health and not-for-profit organisation perspective, to estimate numbers of children under 19 years with life-limiting conditions, cost current services, determine child/parent care preferences, and cost choice of end-of-life care at home. Results: The exemplar locality (North Wales) had important gaps in service provision and the clinical network. The estimated annual total cost of current children’s palliative care was about £5.5 million; average annual care cost per child was £22,771 using 2007 prevalence estimates and £2,437- £11,045 using new 2012/13 population-based prevalence estimates. Using population-based prevalence, we estimate 2271 children with a life-limiting condition in the general exemplar population and around 501 children per year with ongoing palliative care needs in contact with hospital services. Around 24 children with a wide range of life-limiting conditions require end-of-life care per year. Choice of end-of-life care at home was requested, which is not currently universally available. We estimated a minimum (based on 1 week of end-of-life care) additional cost of £336,000 per year to provide end-of-life support at home. Were end-of-life care to span 4 weeks, the total annual additional costs increases to £536,500 (2010/11 prices). Conclusions: Findings make a significant contribution to population-based needs assessment and commissioning methodology in children’s palliative care. Further work is needed to determine with greater precision which children in the total population require access to services and when. Half of children who died 2002-7 did not have conditions that met the globally used children's palliative care condition categories, which need revision in light of findings

    Managing the Socially Marginalized: Attitudes Towards Welfare, Punishment and Race

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    Welfare and incarceration policies have converged to form a system of governance over socially marginalized groups, particularly racial minorities. In both of these policy areas, rehabilitative and social support objectives have been replaced with a more punitive and restrictive system. The authors examine the convergence in individual-level attitudes concerning welfare and criminal punishment, using national survey data. The authors\u27 analysis indicates a statistically significant relationship between punitive attitudes toward welfare and punishment. Furthermore, accounting for the respondents\u27 racial attitudes explains the bivariate relationship between welfare and punishment. Thus, racial attitudes seemingly link support for punitive approaches to opposition to welfare expenditures. The authors discuss the implications of this study for welfare and crime control policies by way of the conclusion

    The Chicken Yolk Sac IgY Receptor, a Mammalian Mannose Receptor Family Member, Transcytoses IgY across Polarized Epithelial Cells

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    In mammals the transfer of passive immunity from mother to young is mediated by the MHC-related receptor FcRn, which transports maternal IgG across epithelial cell barriers. In birds, maternal IgY in egg yolk is transferred across the yolk sac to passively immunize chicks during gestation and early independent life. The chicken yolk sac IgY receptor (FcRY) is the ortholog of the mammalian phospholipase A2 receptor, a mannose receptor family member, rather than an FcRn or MHC homolog. FcRn and FcRY both exhibit ligand binding at the acidic pH of endosomes and ligand release at the slightly basic pH of blood. Here we show that FcRY expressed in polarized mammalian epithelial cells functioned in endocytosis, bidirectional transcytosis, and recycling of chicken FcY/IgY. Confocal immunofluorescence studies demonstrated that IgY binding and endocytosis occurred at acidic but not basic pH, mimicking pH-dependent uptake of IgG by FcRn. Colocalization studies showed FcRY-mediated internalization via clathrin-coated pits and transport involving early and recycling endosomes. Disruption of microtubules partially inhibited apical-to-basolateral and basolateral-to-apical transcytosis, but not recycling, suggesting the use of different trafficking machinery. Our results represent the first cell biological evidence of functional equivalence between FcRY and FcRn and provide an intriguing example of how evolution can give rise to systems in which similar biological requirements in different species are satisfied utilizing distinct protein folds

    Strategies for implementing placental transfusion at birth: a systematic review

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    Background: Enhanced placental transfusion reduces adverse neonatal outcomes, including death. Despite being endorsed by the World Health Organization in 2012, the method has not been adopted widely in practice. Methods: We performed a systematic literature search and included quality improvement projects on placental transfusion at birth and studies on barriers to implementation. We extracted information on population, methods of implementation, obstacles to implementation, and strategies to overcome them. Results: We screened 99 studies out of which 18 were included in the review. The preferred methods of implementation were protocol development (86% of studies) reinforced by targeted education (64% of studies) and multidisciplinary team involvement (43% of studies). Barriers to implementation were mentioned in 12 studies and divided into four categories: general factors such as lack of staff awareness (5 studies) and professional resistance to change (5 studies); obstetrician‐specific concerns, including the impact during cesarean (3 studies) and the risk of postpartum hemorrhage (3 studies); pediatrician‐specific concerns, including the need for resuscitation (5 studies), risk of jaundice (3 studies), and polycythemia (2 studies); and logistical difficulties. The main strategies to facilitate placental transfusion at birth included effective multidisciplinary team collaboration, protocol development, targeted education, and constructive feedback sessions. Conclusions: Placental transfusion implementation requires a multidisciplinary approach, with obstetricians, midwives, nurses, and pediatricians central to adoption of the practice. Understanding the obstacles to implementation informs strategies to increase placental transfusion adoption of practice worldwide. We suggest a stepwise approach to implementation and enhancement of placental transfusion into practice

    Let’s sculpt it! Experiencing the role of context in coaching

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    This exercise aims to familiarize students with the under-discussed topic of the role of context in coaching through a physical activity. It consists of a Group Sculpture – a combination of Socio-drama, Systemic Constellation, Social Presencing Theater – drawing from a coaching case of an ethical dilemma, using the placement and arrangement of participants to represent the stakeholders and context (economic, legal, sociological, etc.). The visual and embodied representation aims to raise awareness and develop understanding of the invisible, but often felt contextual factors at play in coaching, to generate reflection about their influence, and to offer insights on how to identify and embrace them. This activity is primarily aimed for coaching educators and supervisors, but a slightly adapted version could expand its benefits to a more general audience of managers and leaders

    Arabidopsis Seed Coat Mucilage is a Specialized Cell Wall that Can be Used as a Model for Genetic Analysis of Plant Cell Wall Structure and Function

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    Arabidopsis seed coat epidermal cells produce a large quantity of mucilage that is extruded upon exposure to water. Chemical analyses and cell biological techniques suggest that this mucilage represents a specialized type of secondary cell wall composed primarily of pectin with lesser amounts of cellulose and xyloglucan. Once extruded, the mucilage capsule has a distinctive structure with an outer non-adherent layer that is easily removed by shaking in water, and an inner adherent layer that can only be removed with strong acid or base. Most of the cellulose in the mucilage is present in the inner layer and is responsible at least in part for its adherence to the seed. There are also differences in the pectin composition between the two layers that could contribute to the difference in adherence. The Arabidopsis seed coat epidermis and its mucilage are not essential for seed viability or germination. This dispensability, combined with the fact that the epidermal cells synthesize an accessible pectin-rich cell wall at a specific time in development, makes them well suited as a genetic model for studying cell wall biogenesis, function, and regulation. Mutants defective in seed mucilage identified by both forward and reverse genetic analyses are proving useful in establishing connections between carbohydrate structure and cell wall properties in vivo. In the future, genetic engineering of seed coat mucilage carbohydrates should prove useful for testing hypotheses concerning cell wall structure and function

    Collaboration Through NEPA: Achieving a Social License to Operate On Federal Public Lands

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    As demand and consumption of natural gas increases, so will drilling operations to extract the natural gas on federal public lands. Fueled by the shale gas revolution, natural gas drilling operations are now frequently taking place, not only in the highly documented urban settings, but also on federal public lands with high conservation value. The phenomenon of increased drilling in sensitive locations, both urban and remote, has sparked increased public opposition, requiring oil and gas producers to reconsider how they engage the public. Oil and gas producers have increasingly deployed the concept of a social license to operate to gain support from the public and the communities in which they operate. A social license to operate is a voluntary license granted by communities, obligating companies to go above and beyond the requirements of their legal license to operate. While natural gas developers have increasingly sought to achieve a social license to operate in urban settings, such as the Colorado Front Range, there has been little use of this approach by operators drilling on federal public land. We advocate for the use of increased collaboration with affected stakeholders and communities through the NEPA process as a means to achieve a social license to operate on federal public land
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