The Origin of B-Type Runaway Stars: Non-LTE Abundances as a Diagnostic

There are two accepted mechanisms to explain the origin of runaway OB-type stars: the Binary Supernova Scenario (BSS), and the Cluster Ejection Scenario (CES). In the former, a supernova explosion within a close binary ejects the secondary star, while in the latter close multi-body interactions in a dense cluster cause one or more of the stars to be ejected from the region at high velocity. Both mechanisms have the potential to affect the surface composition of the runaway star. TLUSTY non-LTE model atmosphere calculations have been used to determine atmospheric parameters and carbon, nitrogen, magnesium and silicon abundances for a sample of B-type runaways. These same analytical tools were used by Hunter et al. (2009) for their analysis of 50 B-type open cluster Galactic stars (i.e. non-runaways). Effective temperatures were deduced using the silicon-ionization balance technique, surface gravities from Balmer line profiles and microturbulent velocities derived using the Si spectrum. The runaways show no obvious abundance anomalies when compared with stars in the open clusters. The runaways do show a spread in composition which almost certainly reflects the Galactic abundance gradient and a range in the birthplaces of the runaways in the Galactic disk. Since the observed Galactic abundance gradients of C, N, Mg and Si are of a similar magnitude, the abundance ratios (e.g., N/Mg) are, as obtained, essentially uniform across the sample

Benthic organic carbon release stimulates bacterioplankton production in a clear-water subarctic lake

We carried out a set of experiments in a small clear-water lake in northern Sweden during summer 2010 to assess the effect of organic C (OC) released from epipelic algae on pelagic bacterial production (BP). The release rate of OC (dissolved and particulate) from epipelic algae was ,45.4 ng C m22 h21 . Bacterioplankton uptake of dissolved OC was P-limited, and pelagic primary production (PP) was colimited by N and P. Pelagic BP (3.2 6 6 mgCL21 h21 ) exceeded pelagic PP (0.012 6 0.008 mg C L21 h21 ). Pelagic BP was higher in lake water in contact with sediments and the epipelic algae growing on their surface than in water separated from the sediments. Epipelic algae release OC to lake water and potentially stimulate pelagic BP. However, exploitation of benthic OC probably is suboptimal because of nutrient limitation (primarily by inorganic P) of BP.Fil: Rodriguez, Patricia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina; Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina;Fil: Ask, Jenny. Umea University. Department of Ecology and Environmental Science; Suecia;Fil: Hein, Catherine L.. Umea University. Department of Ecology and Environmental Science. Climate Impacts Research Center; Suecia;Fil: Jansson, Mats. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina;Fil: Karlsson, Jan. Umea University. Department of Ecology and Environmental Science. Climate Impacts Research Center; Suecia

Sensational SuperCupboards

While the nation\u27s investment in nutrition assistance is an important and effective tool in fighting hunger and food insecurity, improving the diet quality of low-income Americans remains a major challenge. The SuperCupboard program is a successful community-based approach for educating low-income adults with families, thereby enabling them to prepare and consume healthy, nutritious, and safe diets and to become better managers of their food dollars

Children’s myopia: prevention and the role of school programmes

Exciting solutions are being developed to combat the huge increase in childhood myopia that had become the leading cause of visual impairment, particularly in East Asia. In these settings school-based vision care programmes can make a real difference

The reuse of load-bearing components

Load-bearing systems of buildings are poorly valued when they reach functional obsolescence. Still, they contribute the most to the material weight and embodied impacts of buildings and infrastructures. The reuse of structural components therefore offers great potential to save materials, energy and resources. While historic and contemporary projects highlight the environmental, time or cost benefits of building with reclaimed elements, many technological challenges remain. This paper gives an overview of buildings that efficiently reuse structural components as well as a review of current research efforts addressing structural reuse. The first case study is the design process of an elastic gridshell made from reclaimed skis. This project demonstrates the potential of ensuring structural performance while working with uncharacterized and heterogeneous materials. In general, designing structures from a stock of reclaimed elements entails reversing the conventional structural design process. The synthesis of structures has to follow the availability of elements and their mechanical and geometric properties. Developed tools that facilitate such design from reused elements while minimizing embodied environmental impacts are presented in this paper. A second case study demonstrates the relevance of such tools through a conceptual train station roof made from electric pylon elements. Lastly, some key challenges related to the design of structural systems from reused elements are presented. These research initiatives constitute a first step to understand and support the design of load-bearing systems from reused elements and hence to bring the construction industry closer to circular economy

Embodied Carbon Benefits of Reusing Structural Components in the Built Environment: a Medium-rise Office Building Case Study

This paper provides parametric estimates of embodied carbon reductions when structural components are reused in a typical office building. First, a lower bound of structural material quantities is estimated for a typical steel frame structure in a low-rise office building. The embodied carbon of this conventional design is then compared with values collected from a series of similar existing steel buildings (deQo database) as benchmark. Various scenarios regarding the impact of selective deconstruction, transportation, and cross-section oversizing are modelled and parameterized. The study eventually computes carbon savings over one life cycle of the building project. Results show that reuse remains beneficial for long transport and high oversizing. The discussion calls for more comprehensive studies and refined metrics for quantifying selective deconstruction

Genomic analysis of the chromosome 15q11-q13 Prader-Willi syndrome region and characterization of transcripts for GOLGA8E and WHCD1L1 from the proximal breakpoint region

<p>Abstract</p> <p>Background</p> <p>Prader-Willi syndrome (PWS) is a neurobehavioral disorder characterized by neonatal hypotonia, childhood obesity, dysmorphic features, hypogonadism, mental retardation, and behavioral problems. Although PWS is most often caused by a paternal interstitial deletion of a 6-Mb region of chromosome 15q11-q13, the identity of the exact protein coding or noncoding RNAs whose deficiency produces the PWS phenotype is uncertain. There are also reports describing a PWS-like phenotype in a subset of patients with full mutations in the <it>FMR1 </it>(fragile X mental retardation 1) gene. Taking advantage of the human genome sequence, we have performed extensive sequence analysis and molecular studies for the PWS candidate region.</p> <p>Results</p> <p>We have characterized transcripts for the first time for two UCSC Genome Browser predicted protein-coding genes, <it>GOLGA8E </it>(golgin subfamily a, 8E) and <it>WHDC1L1 </it>(WAS protein homology region containing 1-like 1) and have further characterized two previously reported genes, <it>CYF1P1 </it>and <it>NIPA2</it>; all four genes are in the region close to the proximal/centromeric deletion breakpoint (BP1). <it>GOLGA8E</it> belongs to the golgin subfamily of coiled-coil proteins associated with the Golgi apparatus. Six out of 16 golgin subfamily proteins in the human genome have been mapped in the chromosome 15q11-q13 and 15q24-q26 regions. We have also identified more than 38 copies of <it>GOLGA8E</it>-like sequence in the 15q11-q14 and 15q23-q26 regions which supports the presence of a <it>GOLGA8E</it>-associated low copy repeat (LCR). Analysis of the 15q11-q13 region by PFGE also revealed a polymorphic region between BP1 and BP2. <it>WHDC1L1 </it>is a novel gene with similarity to mouse <it>Whdc1 </it>(WAS protein homology region 2 domain containing 1) and human JMY protein (junction-mediating and regulatory protein). Expression analysis of cultured human cells and brain tissues from PWS patients indicates that <it>CYFIP1 </it>and <it>NIPA2</it> are biallelically expressed. However, we were not able to determine the allele-specific expression pattern for <it>GOLGA8E </it>and <it>WHDC1L1 </it>because these two genes have highly related sequences that might also be expressed.</p> <p>Conclusion</p> <p>We have presented an updated version of a sequence-based physical map for a complex chromosomal region, and we raise the possibility of polymorphism in the genomic orientation of the BP1 to BP2 region. The identification of two new proteins <it>GOLGA8E</it> and <it>WHDC1L1</it> encoded by genes in the 15q11-q13 region may extend our understanding of the molecular basis of PWS. In terms of copy number variation and gene organization, this is one of the most polymorphic regions of the human genome, and perhaps the single most polymorphic region of this type.</p

Exploration of meaning, motivation, and preparedness to care amongst the one-child policy generation in China

YesIn China there is a cultural expectation (Xiao, -filial piety) that offspring should provide care for their parents. However, the sustainability of this is threatened by the impact of the One-Child Policy (OCP) (1979-2015), which has resulted in a diminution in numbers of children available to care, rapid urbanisation and increase in the number of women in employment. In this context, the objective was to explore the motivations, meaning, and preparedness for future caregiving of offspring affected by the OCP. We adopted a constructivist position using a hermeneutic phenomenology approach and interviewed eight current and prospective caregivers aged 20-35 years about future caregiving responsibilities. Data were obtained through in-depth interviews, analysed using reflective Thematic Analysis. Three prominent themes: (i) Caregiving beliefs, (ii) Caregiving conditions and (iii) Contextual factors were identified under an overarching theme "Competing pressures-meanings, motivation and preparedness". Despite the inherent stress, participants envisaged providing or organising care in the future to fulfil Xiao, and most viewed long-term care settings as unviable. Ultimately, the findings suggested that the actual performance of caregiving would not always measure up to ideal expectations, resulting in 'filial discrepancy' that is, a gap between societal expectations for caregiving to older relatives and actual caregiving performance. This could adversely impact the caregivers and quality of care provided. The findings highlighted the urgent need to develop culturally attuned services, including education and training for family caregivers, health and social care professionals.This work was supported by Research England: Quality Related Global Challenge Research Fund; University of Bradford

Not Hot, but Sharp: Dissociation of Pinprick and Heat Perception in Snake Eye Appearance Myelopathy

Following a traumatic spinal cord injury, a 53-year-old male developed a central cord syndrome with at-level neuropathic pain. Magnetic resonance imaging revealed a classical “snake eye” appearance myelopathy, with marked hyperintensities at C5-C7. Clinical examination revealed intact pinprick sensation coupled with lost or diminished thermal/heat sensation. This dissociation could be objectively confirmed through multi-modal neurophysiological assessments. Specifically, contact heat evoked potentials were lost at-level, while pinprick evoked potentials were preserved. This pattern corresponds with that seen after surgical commissural myelotomy. To our knowledge, this is the first time such a dissociation has been objectively documented, highlighting the diagnostic potential of multi-modal neurophysiological assessments. In future studies, a comprehensive assessment of different nociceptive modalities may help elucidate the pathophysiology of neuropathic pain

Aquilegia, Vol. 32 No. 3, Fall 2008, Newsletter of the Colorado Native Plant Society

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