79 resultados para intergenerational transfers


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In this paper we report an empirical study of the photographic portrayal of family members at home. Adopting a social psychological approach and focusing oil intergenerational power dynamics, our research explores the use of domestic photo displays in family representation. Parents and their teenagers from eight families in the south of England were interviewed at home about their interpretations of both stored and displayed photos within the home. Discussions centred on particular photographs found by the participants to portray self and family in different ways. The findings show that public displays of digital photos are still curated by mothers of the households, but with more difficulty and less control all with analogue photos. In addition, teenagers both contribute and comply with this curation within the home, whilst at the same time developing additional ways of presenting their families and themselves online that are 'unsupervised' by the curator. We highlight the conflict of interest that is at play within teen and parent practices and consider the challenges that this presents for supporting the representation of family through the design of photo display technology. (C) 2009 Elsevier Ltd. All rights reserved.

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Charge exchange (CE) plays a fundamental role in the collisions of solar- and stellar-wind ions with lunar and planetary exospheres, comets, and circumstellar clouds. Reported herein are absolute cross sections for single, double, triple, and quadruple CE of Feq+ (q = 5-13) ions with H2O at a collision energy of 7q keV. One measured value of the pentuple CE is also given for Fe9+ ions. An electron cyclotron resonance ion source is used to provide currents of the highly charged Fe ions. Absolute data are derived from knowledge of the target gas pressure, target path length, and incident and charge-exchanged ion currents. Experimental cross sections are compared with new results of the n-electron classical trajectory Monte Carlo approximation. The radiative and non-radiative cascades following electron transfers are approximated using scaled hydrogenic transition probabilities and scaled Auger rates. Also given are estimates of cross sections for single capture, and multiple capture followed by autoionization, as derived from the extended overbarrier model. These estimates are based on new theoretical calculations of the vertical ionization potentials of H2O up to H2O10+.

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Polyopes lancifolius (Harvey) S. Kawaguchi & H.W. Wang has been recorded for the first time in Europe, during the summer or 2008. A small population was discovered in the Gulf of Morbihan (northeast Atlantic, France). This is the first observation of P. lancifolius outside its native range. Vegetative and reproductive morphological features are compared with previous descriptions. rbcL sequences show no divergence from Japanese populations. Imports of Pacific oysters Crassostrea gigas (Thunberg 1793) are likely to be responsible for its accidental introduction into the Gulf of Morbihan, either directly from northwest Pacific regions or indirectly (secondary dispersal) by transfers from another European oyster farming site. The history of previous algal introductions from Japan suggests that if it becomes successfully established at Morbihan, the species is likely to spread to other European coastal areas.

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This study addresses one of the shortcomings apparent in previous research on expatriate job-transfers, namely the lack of exploratory, empirical groundwork into the motives of expatriates to seek or accept international assignments. The relocatee population of a large German MNC was surveyed for their motives to seek or accept their transfer, using an open-response format. Responses were content analysed in order to arrive at an empirically grounded set of motives. The findings provide a very detailed picture of employees' motives to seek or accept international assignments and thus an important interim result that, when used as input in subsequent investigations, promises highly relevant results due to established content validity.

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The validity of load estimates from intermittent, instantaneous grab sampling is dependent on adequate spatial coverage by monitoring networks and a sampling frequency that re?ects the variability in the system under study. Catchments with a ?ashy hydrology due to surface runoff pose a particular challenge as intense short duration rainfall events may account for a signi?cant portion of the total diffuse transfer of pollution from soil to water in any hydrological year. This can also be exacerbated by the presence of strong background pollution signals from point sources during low flows. In this paper, a range of sampling methodologies and load estimation techniques are applied to phosphorus data from such a surface water dominated river system, instrumented at three sub-catchments (ranging from 3 to 5 km2 in area) with near-continuous monitoring stations. Systematic and Monte Carlo approaches were applied to simulate grab sampling using multiple strategies and to calculate an estimated load, Le based on established load estimation methods. Comparison with the actual load, Lt, revealed signi?cant average underestimation, of up to 60%, and high variability for all feasible sampling approaches. Further analysis of the time series provides an insight into these observations; revealing peak frequencies and power-law scaling in the distributions of P concentration, discharge and load associated with surface runoff and background transfers. Results indicate that only near-continuous monitoring that re?ects the rapid temporal changes in these river systems is adequate for comparative monitoring and evaluation purposes. While the implications of this analysis may be more tenable to small scale ?ashy systems, this represents an appropriate scale in terms of evaluating catchment mitigation strategies such as agri-environmental policies for managing diffuse P transfers in complex landscapes.

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A central element in the privatization of council housing has been the development of stock transfer policy. A variety of perspectives on this process have been explored including the impact on accountability relations; however, the tenants’ experience is almost completely absent from this literature. The paper develops a case study that draws on the experience of the tenants involved in a stock transfer. In the process stock transfers, and related accountability relations, are shown to be contested with tenant-led campaigns challenging this neoliberal inspired policy. The case study illustrates the power and financial resource asymmetries in transfer campaigns with a range of anti-democratic tactics employed by those pursuing the transfer. On the basis of a critique of neoliberalism, the stock transfer process is seen as an attack on the previous democratic control of council housing, which is replaced with ‘governance by experts and elites’ and private sector inspired corporate governance forms of accountability. Thus the paper seeks to answer two questions; how democratic is the transfer process and what are the long-term implications for democratic accountability in the social housing sector.

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Per-core scratchpad memories (or local stores) allow direct inter-core communication, with latency and energy advantages over coherent cache-based communication, especially as CMP architectures become more distributed. We have designed cache-integrated network interfaces, appropriate for scalable multicores, that combine the best of two worlds – the flexibility of caches and the efficiency of scratchpad memories: on-chip SRAM is configurably shared among caching, scratchpad, and virtualized network interface (NI) functions. This paper presents our architecture, which provides local and remote scratchpad access, to either individual words or multiword blocks through RDMA copy. Furthermore, we introduce event responses, as a technique that enables software configurable communication and synchronization primitives. We present three event response mechanisms that expose NI functionality to software, for multiword transfer initiation, completion notifications for software selected sets of arbitrary size transfers, and multi-party synchronization queues. We implemented these mechanisms in a four-core FPGA prototype, and measure the logic overhead over a cache-only design for basic NI functionality to be less than 20%. We also evaluate the on-chip communication performance on the prototype, as well as the performance of synchronization functions with simulation of CMPs with up to 128 cores. We demonstrate efficient synchronization, low-overhead communication, and amortized-overhead bulk transfers, which allow parallelization gains for fine-grain tasks, and efficient exploitation of the hardware bandwidth.

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Abstract: Critical source area approaches to catchment management are increasingly being recognised as effective tools to mitigate sediment and nutrient transfers. These approaches often assume hydrological connectivity as a driver for environmental risk, however this assumption has rarely been tested. Using high resolution monitoring, 14 rainfall events of contrasting intensity were examined in detail for spatial and temporal dynamics of overland flow generation at a hydrologically isolated grassland hillslope in Co. Down, Northern Ireland. Interactions between overland flow connectivity and nutrient transfers were studied to test the critical source area hypothesis. While total and soluble phosphorus loads were found to be representative of the size of the overland flow contributing area (P=

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Introduction: Infections by multidrug-resistant bacteria are of great concern worldwide. In many cases, resistance is not due to the presence of specific antibiotic-modifying enzymes, but rather associated with a general impermeability of the bacterial cell envelope. The molecular bases of this intrinsic resistance are not completely understood. Moreover, horizontal gene transfers cannot solely explain the spread of intrinsic resistance among bacterial strains. Areas covered: This review focuses on the increased intrinsic antibiotic resistance mediated by small molecules. These small molecules can either be secreted from bacterial cells of the same or different species (e.g., indole, polyamines, ammonia, and the Pseudomonas quinolone signal) or be present in the bacterial cell milieu, whether in the environment, such as indole acetic acid and other plant hormones, or in human tissues and body fluids, such as polyamines. These molecules are metabolic byproducts that act as infochemicals and modulate bacterial responses toward antibiotics leading to increasing or decreasing resistance levels. Expert opinion: The non-genetic mechanisms of antibiotic response modulation and communication discussed in this review should reorient our thinking of the mechanisms of intrinsic resistance to antibiotics and its spread across bacterial cell populations. The identification of chemical signals mediating increased intrinsic antibiotic resistance will expose novel critical targets for the development of new antimicrobial strategies.

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The recycling of the lipid carrier undecaprenyl-phosphate (Und-P) requires the dephosphorylation of Und-PP, a reaction proposed to occur at the external or periplasmic side of the bacterial cell membrane. In this issue of Molecular Microbiology, experiments based on the analysis of lipopolysaccharide modifications in Escherichia coli demonstrate that the phosphorylation of lipid A at position 1 is catalysed by the membrane enzyme LpxT (formerly YeiU). This enzyme specifically transfers the distal phosphate group from Und-PP to lipid A 1-phosphate to produce lipid A 1-diphosphate. Furthermore, this reaction requires a functionally intact MsbA protein, which catalyses the transfer of lipid A across the membrane, confirming that the LpxT-mediated lipid A modification occurs on the periplasmic side of the membrane. These observations provide a novel and unexpected link between periplasmic lipid A modifications and the Und-PP recycling pathway.

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The glycan chain of the S-layer glycoprotein of Geobacillus stearothermophilus NRS 2004/3a is composed of repeating units [-->2)-alpha-l-Rhap-(1-->3)-beta-l-Rhap-(1-->2)-alpha-l-Rhap-(1-->], with a 2-O-methyl modification of the terminal trisaccharide at the nonreducing end of the glycan chain, a core saccharide composed of two or three alpha-l-rhamnose residues, and a beta-d-galactose residue as a linker to the S-layer protein. In this study, we report the biochemical characterization of WsaP of the S-layer glycosylation gene cluster as a UDP-Gal:phosphoryl-polyprenol Gal-1-phosphate transferase that primes the S-layer glycoprotein glycan biosynthesis of Geobacillus stearothermophilus NRS 2004/3a. Our results demonstrate that the enzyme transfers in vitro a galactose-1-phosphate from UDP-galactose to endogenous phosphoryl-polyprenol and that the C-terminal half of WsaP carries the galactosyltransferase function, as already observed for the UDP-Gal:phosphoryl-polyprenol Gal-1-phosphate transferase WbaP from Salmonella enterica. To confirm the function of the enzyme, we show that WsaP is capable of reconstituting polysaccharide biosynthesis in WbaP-deficient strains of Escherichia coli and Salmonella enterica serovar Typhimurium.

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Campylobacter jejuni has a general N-linked protein glycosylation system that can be functionally transferred to Escherichia coli. In this study, we engineered E. coli cells in a way that two different pathways, protein N-glycosylation and lipopolysaccharide (LPS) biosynthesis, converge at the step in which PglB, the key enzyme of the C. jejuni N-glycosylation system, transfers O polysaccharide from a lipid carrier (undecaprenyl pyrophosphate) to an acceptor protein. PglB was the only protein of the bacterial N-glycosylation machinery both necessary and sufficient for the transfer. The relaxed specificity of the PglB oligosaccharyltransferase toward the glycan structure was exploited to create novel N-glycan structures containing two distinct E. coli or Pseudomonas aeruginosa O antigens. PglB-mediated transfer of polysaccharides might be valuable for in vivo production of O polysaccharides-protein conjugates for use as antibacterial vaccines.

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The relationship between parental background and children's educational outcomes has been a dominant theme within the sociology of education. There has been an on-going debate as to the relative merits of explanations which focus on the role of socio-cultural reproduction and those which focus on rational choice. However, many empirical studies within the social stratification tradition fail to allow for children's own agency in shaping the relationship between social background and schooling outcomes. This paper draws on the first wave of a large-scale longitudinal study of over 8,000 nine-year-old children in Ireland, which combines information from parents, school principals, teachers and children themselves. Both social class and parental education are found to have significant effects on reading and mathematics test scores among nine year olds. These effects are partly mediated by home-based educational resources and activities, parents' educational expectations for their child, and parents' formal involvement in the school. More importantly, children's own engagement with, and attitudes to, school significantly influence their academic performance. The influence of children's own attitudes and actions can thus reinforce or mitigate the effect of social background factors. The analysis therefore provides a bridge between the large body of research on the intergenerational transmission of inequality and the emerging research and policy literature on children's rights.