2,331 research outputs found

    Evaluation of Mobility Modes on Lunar Exploration Traverses - Marius Hills, Copernicus Peaks, and Hadley Apennines Missions

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    Energy and time costs of lunar walking or riding traverses, and scientific tasks on J-type missions, and capabilities of A7L suits and life support system

    Understanding fans' responses to the sponsor of a rival team

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    Research Question What factors determine fans’ responses to the sponsor of a rival team? To what extent does higher in-group fan identification, more positive prior attitudes to the sponsor, and a more congruent fit between the sponsor and club, cause denigration or mitigate negative outcomes for the sponsor? Research Methods 300 questionnaires were collected from fans of English Premier League (EPL) football teams Newcastle United and Sunderland allowed us to test our model of sponsorship responses. Structural equation modelling (SEM) was used to evaluate each hypothesis. Results and Findings Brands will gain greater benefits from sponsorships deemed to be congruent with the rival team and where a higher pre-sponsorship attitude exists. More highly identified fans tend to pay greater attention to the sponsor of their rival team. We find that schadenfreude is a better predictor of affective and behavioural responses than fan identification, despite its popularity in recent research involving rival fans. Implications Brand managers concerned about the size and scope of out-groups can employ our findings to more effectively configure sponsorship activities

    Don't Distract Me When I'm Media Multitasking: Toward a Theory for Raising Advertising Recall and Recognition

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    Media multitasking, such as using handheld devices like smartphones and tablets while watching TV, has become prevalent but its effect on the recall and recognition of advertising subject to limited academic research. We contend that the context in which multitasking takes place affects consumer memory for advertising delivered via the primary activity (e.g., watching television). Specifically, we identify the importance of the degree of (a) congruence between the primary and second screen activity and (b) social accountability of second screen activities. We test our typology empirically by examining the determinants of next day recall and recognition for billboard advertisers (perimeter board advertisements) of a televised football (soccer) match. In line with our theory, in most cases media multitasking leads to worse recall and recognition, however, in situations where there is congruence between primary and second screen activities and secondary activities have a higher level of social accountability attached to them, then advertising recall and recognition improves

    Maternal colonization with Staphylococcus aureus and Group B streptococcus is associated with colonization in newborns.

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    OBJECTIVES: Although Staphylococcus aureus and Group B streptococcus (GBS) are major causes of neonatal sepsis in sub-Saharan Africa, it is unclear how these bacteria are transmitted to the neonate. METHODS: In a cohort of 377 Gambian women and their newborns, nasopharyngeal swabs were collected at delivery (day 0), and 3, 6, 14 and 28 days later. Breast milk samples and vaginal swabs were collected from the mother. Staphylococcus aureus and GBS were isolated using conventional microbiological methods. RESULTS: Most women were carriers of S. aureus (264 out of 361 with all samples collected, 73.1%) at some point during follow up and many were carriers of GBS (114 out of 361, 31.6%). Carriage of S. aureus was common in all three maternal sites and GBS was common in the vaginal tract and breast milk. Among newborns, carriage of S. aureus peaked at day 6 (238 out of 377, 63.1%) and GBS at day 3 (39 out of 377, 10.3%). Neonatal carriage of S. aureus at day 6 was associated with maternal carriage in the breast milk adjusted OR 2.54; 95% CI 1.45-4.45, vaginal tract (aOR 2.55; 95% CI 1.32-4.92) and nasopharynx (aOR 2.49; 95% CI 1.56-3.97). Neonatal carriage of GBS at day 6 was associated with maternal carriage in the breast milk (aOR 3.75; 95% CI 1.32-10.65) and vaginal tract (aOR 3.42; 95% CI 1.27-9.22). CONCLUSIONS: Maternal colonization with S. aureus or GBS is a risk factor for bacterial colonization in newborns

    Competitiveness and communication for effective inoculation byRhizobium, Bradyrhizobium and vesicular-arbuscular mycorrhiza fungi

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    After a short summary on the ecology and rhizosphere biology of symbiotic bacteria and vesicular-arbuscular (VA) mycorrhiza fungi and their application as microbial inocula, results on competitiveness and communication are summarized. Stress factors such as high temperature, low soil pH, aluminium concentrations and phytoalexins produced by the host plants were studied withRhizobium leguminosarum bv.phaseoli andRhizobium tropici onPhaseolus beans. Quantitative data for competitiveness were obtained by usinggus + (glucoronidase) labelled strains, which produce blue-coloured nodules. ForPhaseolus-nodulating rhizobia, a group specific DNA probe was also developed, which did not hybridize with more than 20 other common soil and rhizosphere bacteria. Results from several laboratories contributing to knowledge of signal exchange and communication in theRhizobium/Bradyrhizobium legume system are summarized in a new scheme, including also defense reactions at the early stages of legume nodule initiation. Stimulating effects of flavonoids on germination and growth of VA mycorrhiza fungi were also found. A constitutive antifungal compound in pea roots, -isoxazolinonyl-alanine, was characterized

    Formation and stability of self-assembled coherent islands in highly mismatched heteroepitaxy

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    We study the energetics of island formation in Stranski-Krastanow growth within a parameter-free approach. It is shown that an optimum island size exists for a given coverage and island density if changes in the wetting layer morphology after the 3D transition are properly taken into account. Our approach reproduces well the experimental island size dependence on coverage, and indicates that the critical layer thickness depends on growth conditions. The present study provides a new explanation for the (frequently found) rather narrow size distribution of self-assembled coherent islands.Comment: 4 pages, 5 figures, In print, Phys. Rev. Lett. Other related publications can be found at http://www.fhi-berlin.mpg.de/th/paper.htm

    Effects of anharmonic strain on phase stability of epitaxial films and superlattices: applications to noble metals

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    Epitaxial strain energies of epitaxial films and bulk superlattices are studied via first-principles total energy calculations using the local-density approximation. Anharmonic effects due to large lattice mismatch, beyond the reach of the harmonic elasticity theory, are found to be very important in Cu/Au (lattice mismatch 12%), Cu/Ag (12%) and Ni/Au (15%). We find that is the elastically soft direction for biaxial expansion of Cu and Ni, but it is for large biaxial compression of Cu, Ag, and Au. The stability of superlattices is discussed in terms of the coherency strain and interfacial energies. We find that in phase-separating systems such as Cu-Ag the superlattice formation energies decrease with superlattice period, and the interfacial energy is positive. Superlattices are formed easiest on (001) and hardest on (111) substrates. For ordering systems, such as Cu-Au and Ag-Au, the formation energy of superlattices increases with period, and interfacial energies are negative. These superlattices are formed easiest on (001) or (110) and hardest on (111) substrates. For Ni-Au we find a hybrid behavior: superlattices along and like in phase-separating systems, while for they behave like in ordering systems. Finally, recent experimental results on epitaxial stabilization of disordered Ni-Au and Cu-Ag alloys, immiscible in the bulk form, are explained in terms of destabilization of the phase separated state due to lattice mismatch between the substrate and constituents.Comment: RevTeX galley format, 16 pages, includes 9 EPS figures, to appear in Physical Review

    Crystal growth and elasticity

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    The purpose of this paper is to review some elasticity effects in epitaxial growth. We start by a description of the main ingredients needed to describe elasticity effects (elastic interactions, surface stress, bulk and surface elasticity, thermodynamics of stressed solids). Then we describe how bulk and surface elasticity affect growth mode and surface morphology by means of stress-driven instability. At last stress-strain evolution during crystal growth is reported.Comment: 12 page

    Haemolysis and haem oxygenase-1 induction during persistent "asymptomatic" malaria infection in Burkinabé children

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    BACKGROUND: The haemolysis associated with clinical episodes of malaria results in the liberation of haem, which activates the enzyme haem oxygenase-1 (HO-1). HO-1 has been shown to reduce neutrophil function and increase susceptibility to invasive bacterial disease. However, the majority of community-associated malaria infections are subclinical, often termed "asymptomatic" and the consequences of low-grade haemolysis during subclinical malaria infection are unknown. STUDY DESIGN AND RESULTS: As part of an ongoing study of subclinical malaria in Burkina Faso, 23 children with subclinical Plasmodium falciparum infections (determined by qPCR) were compared with 21 village-matched uninfected control children. Infected children showed evidence of persistent haemolysis over 35 days, with raised plasma haem and HO-1 concentrations. Concentrations of IL-10, which can also directly activate HO-1, were also higher in infected children compared to uninfected children. Regression analysis revealed that HO-1 was associated with haemolysis, but not with parasite density, anaemia or IL-10 concentration. CONCLUSIONS: This study reveals that subclinical P. falciparum malaria infection is associated with sustained haemolysis and the induction of HO-1. Given the association between HO-1, neutrophil dysfunction and increased risk of Salmonella bacteraemia, prolonged HO-1 induction may explain epidemiological associations and geographic overlap between malaria and invasive bacterial disease. Further studies are needed to understand the consequences of persistent subclinical malaria infection, low-grade haemolysis and raised HO-1 on immune cell function and risk of comorbidities
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