5,593 research outputs found
STOL aircraft transient ground effects. Part 1: Fundamental analytical study
The first phases of a fundamental analytical study of STOL ground effects were presented. Ground effects were studied in two dimensions to establish the importance of nonlinear effects, to examine transient aspects of ascent and descent near the ground, and to study the modelling of the jet impingement on the ground. Powered lift system effects were treated using the jet-flap analogy. The status of a three-dimensional jet-wing ground effect method was presented. It was shown, for two-dimensional unblown airfoils, that the transient effects are small and are primarily due to airfoil/freestream/ground orientation rather than to unsteady effects. The three-dimensional study showed phenomena similar to the two-dimensional results. For unblown wings, the wing/freestream/ground orientation effects were shown to be of the same order of magnitude as for unblown airfoils. This may be used to study the nonplanar, nonlinear, jet-wing ground effect
The effect of material cyclic deformation properties on residual stress generation by laser shock processing
Continuous Acquisition of MHC:Peptide Complexes by Recipient Cells Contributes to the Generation of Anti-Graft CD8+ T Cell Immunity
Understanding the evolution of the direct and indirect pathways of allorecognition following tissue transplantation is essential in the design of tolerance‐promoting protocols. On the basis that donor bone marrow–derived antigen‐presenting cells are eliminated within days of transplantation, it has been argued that the indirect response represents the major threat to long‐term transplant survival, and is consequently the key target for regulation. However, the detection of MHC transfer between cells, and particularly the capture of MHC:peptide complexes by dendritic cells (DCs), led us to propose a third, semidirect, pathway of MHC allorecognition. Persistence of this pathway would lead to sustained activation of direct‐pathway T cells, arguably persisting for the life of the transplant. In this study, we focused on the contribution of acquired MHC‐class I on recipient DCs during the life span of a skin graft. We observed that MHC‐class I acquisition by recipient DCs occurs for at least 1 month following transplantation and may be the main source of alloantigen that drives CD8(+) cytotoxic T cell responses. In addition, acquired MHC‐class I:peptide complexes stimulate T cell responses in vivo, further emphasizing the need to regulate both pathways to induce indefinite survival of the graft
Learning behaviour and learning outcomes : the roles for social influence and field of study
Research has demonstrated a significant role of discipline social identification in predicting learning approaches, even controlling for individual differences. Smyth et al. (Educ Psychol 35(1):53–72, 2015. doi:10.1080/01443410.2013.822962) suggest that learners share discipline-based social identifications, and that this identification, in combination with relevant norms, influences the adoption of learning approaches. The current paper extends this analysis in two directions. First, the effect of broad field of study is examined for systematic differences across content domains. Secondly, the model examines effects on student perceptions of teaching quality and intentions to continue within a discipline. Results provide support for Smyth et al.’s (2015) model, demonstrating links between discipline identification, perceived norms, learning approaches and outcomes. Strongly identified students, students who perceived deep learning norms and students taking a deep learning approach all reported more positive outcomes. Disciplinary variations in responses to learning approaches and outcomes were also found, broadly in line with that found in the Biglan–Becher literature.PostprintPeer reviewe
Innovation and the co-creation of value in construction
Construction businesses balance market and project risks in resourcing innovation and value creation. Technical, technological and management innovation are considered using the marketing lens of the service-dominant logic. The co-creation of value is a primary concept, which is largely unexplored in construction, especially related to innovation. Co-created by main contractors and clients is defined as value generated in context and use.
The paper is part of a programme of work, applying an interpretative qualitative approach. The method for data collection was semi-structured interviews, derived from six major international main contractors. Thirty-nine interviews were conducted with a range of senior management, functional heads and project managers responsible for identifying innovation and value creation opportunities.
The overall findings fall into three main areas. First, management perceived construction to be suppliers of technical expertise. Second, projects are perceived in terms of expert inputs. Third, associated tasks are conducted to meet programme schedules and requirements. Opportunities to co-create value are largely pursued reactively and opportunities to innovate through top down or project induced capabilities are largely overlooked. Where innovation occurred it was largely initiated through a combination of co-creation drivers supported by management pull factors rather than innovation drivers and a technology push
Electrochemistry and application of a novel monosubstituted squarate electron-transfer mediator in a glucose oxidase-doped poly(phenol) sensor
Electrosynthetic poly(phenol) nanofilms were deposited in situ on platinum electrodes
in the presence and absence of glucose oxidase. The synthesis charges and currents of
the nonconducting polymer films were recorded at various applied potentials for films grown
from 25–100 mM phenol concentrations. Film parameters such as the standard rate constant
for film deposition, film thickness, and surface concentration of the poly(phenol) films were
evaluated from the cyclic and step voltammograms of the polymerization process. A novel
electron-transfer mediator consisting of monosubstituted 4-hydroxycyclobut-3-ene-1,2-dione
(squarate) was used as a mediator for Pt/poly(phenol) nano-film/GOx amperometric glucose
biosensors. Amperometric responses for 3-diphenylamino-4-hydroxycyclobut-3-ene-1,2-
dione (diphenylaminosquarate: E°′ = of +328 mV/Ag-AgCl at pH 7.0)-mediated systems
were measured by both steady-state amperometric and cyclic voltammetry. The sensor sensitivity
was calculated to be 558 nA cm
–2
(µM)
–1
Loci for primary ciliary dyskinesia map to chromosome 16p12.1-12.2 and 15q13.1-15.1 in Faroe Islands and Israeli Druze genetic isolates
Secondary literacy across the curriculum: Challenges and possibilities
This paper discusses the challenges and possibilities attendant upon successfully implementing literacy across the curriculum initiatives – or ‘school language policies’ as they have come to be known - particularly at the secondary or high school level. It provides a theoretical background to these issues, exploring previous academic discussions of school language policies, and highlights key areas of concern as well as opportunity with respect to school implementation of such policies. As such, it provides a necessary conceptual background to the subsequent papers in this special issue, which focus upon the Secondary Schools’ Literacy Initiative (SSLI) – a New Zealand funded programme that aims to establish cross-curricular language and literacy policies in secondary schools
Prediction of dry powder inhaler formulation performance from surface energetics and blending dynamics
The Purpose of these studies was to investigate the ability of surface energy measurements and rates of mixing in dry powder inhaler formulations to predict aerosol dispersion performance. Two lactose carrier systems comprising either spray dried or milled particles were developed such that they had identical physical characteristics except for surface morphology and surface energies avoiding confounding variables common in other studies. Surface energy measurements confirmed significant differences between the powder systems. Spray dried lactose had a higher surface entropy (0.20 vs.
0.13 mJ/m2K) and surface enthalpy (103.2 vs. 79.2 mJ/m2) compared to milled lactose. Mixing rates of budesonide or fluorescein were assessed dynamically and significant differences in blending were observed between lactose systems for both drugs. Surface energies of the lactose carriers were inversely proportional to dispersion performance. In addition, the root mean square of blending rates correlated positively with aerosol dispersion performance. Both techniques have potential utility in routine screening dry powder inhaler formulations
Two-Level Atom in an Optical Parametric Oscillator: Spectra of Transmitted and Fluorescent Fields in the Weak Driving Field Limit
We consider the interaction of a two-level atom inside an optical parametric
oscillator. In the weak driving field limit, we essentially have an atom-cavity
system driven by the occasional pair of correlated photons, or weakly squeezed
light. We find that we may have holes, or dips, in the spectrum of the
fluorescent and transmitted light. This occurs even in the strong-coupling
limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a
sub-natural linewidth may occur. These effects disappear for larger driving
fields, unlike the spectral narrowing obtained in resonance fluorescence in a
squeezed vacuum; here it is important that the squeezing parameter tends to
zero so that the system interacts with only one correlated pair of photons at a
time. We show that a previous explanation for spectral narrowing and spectral
holes for incoherent scattering is not applicable in the present case, and
propose a new explanation. We attribute these anomalous effects to quantum
interference in the two-photon scattering of the system.Comment: 10 pages, 17 figures, submitted to Phys Rev
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