7,581 research outputs found
Holistic facial composite creation and subsequent video line-up eyewitness identification paradigm
The paradigm detailed in this manuscript describes an applied experimental method based on real police investigations during which an eyewitness or victim to a crime may create from memory a holistic facial composite of the culprit with the assistance of a police operator. The aim is that the composite is recognized by someone who believes that they know the culprit. For this paradigm, participants view a culprit actor on video and following a delay, participant-witnesses construct a holistic system facial composite. Controls do not construct a composite. From a series of arrays of computer-generated, but realistic faces, the holistic system construction method primarily requires participant-witnesses to select the facial images most closely meeting their memory of the culprit. Variation between faces in successive arrays is reduced until ideally the final image possesses a close likeness to the culprit. Participant-witness directed tools can also alter facial features, configurations between features and holistic properties (e.g., age, distinctiveness, skin tone), all within a whole face context. The procedure is designed to closely match the holistic manner by which humans’ process faces. On completion, based on their memory of the culprit, ratings of composite-culprit similarity are collected from the participant-witnesses. Similar ratings are collected from culprit-acquaintance assessors, as a marker of composite recognition likelihood. Following a further delay, all participants — including the controls — attempt to identify the culprit in either a culprit-present or culprit-absent video line-up, to replicate circumstances in which the police have located the correct culprit, or an innocent suspect. Data of control and participant-witness line-up outcomes are presented, demonstrating the positive influence of holistic composite construction on identification accuracy. Correlational analyses are conducted to measure the relationship between assessor and participant-witness composite-culprit similarity ratings, delay, identification accuracy, and confidence to examine which factors influence video line-up outcomes
IMAGE, the First of the NEW MIDEX Missions
The Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) mission will be the first of the new Mediumclass Explorer (MIDEX) missions to fly. Led by Southwest Research Institute with oversight from the Explorers Project Office at NASA GSFC, IMAGE is the first satellite mission dedicated to imaging the Earth\u27s magnetosphere. IMAGE will utilize a combination of ultraviolet and neutral atom imaging instruments plus an RF sounder to map and image the temporal and spatial features of the magnetosphere. The eight science sensors are mounted to a single deckplate. The deckplate is enveloped in an eight-sided spacecraft bus, 225 cm across the flats, developed by Lockheed Martin Missiles and Space Corporation. Constructed of laminated aluminum honeycomb panels, covered extensively by Gallium Arsenide solar cells, the spacecraft structure is designed to withstand the launch loads of a Delta 7326-9.5 ELV. Attitude control is via a single magnetic torque rod and passive nutation damper with aspect information provided by a star camera, sun sensor, and three-axis magnetometer. A single S-band transponder provides telemetry and command functionality. Interfaces between the self-contained payload and the spacecraft are limited to MIL-STD-1553 and power. This paper describes the IMAGE mission as well as the engineering details of the spacecraft
Nanometric depth resolution from multi-focal images in microscopy
We describe a method for tracking the position of small features in three dimensions from images recorded on a standard microscope with an inexpensive attachment between the microscope and the camera. The depth-measurement accuracy of this method is tested experimentally on a wide-field, inverted microscope and is shown to give approximately 8 nm depth resolution, over a specimen depth of approximately 6 µm, when using a 12-bit charge-coupled device (CCD) camera and very bright but unresolved particles. To assess low-flux limitations a theoretical model is used to derive an analytical expression for the minimum variance bound. The approximations used in the analytical treatment are tested using numerical simulations. It is concluded that approximately 14 nm depth resolution is achievable with flux levels available when tracking fluorescent sources in three dimensions in live-cell biology and that the method is suitable for three-dimensional photo-activated localization microscopy resolution. Sub-nanometre resolution could be achieved with photon-counting techniques at high flux levels
High-throughput tertiary amine deoxygenated photopolymerizations for synthesizing polymer libraries
The huge chemical space potential of synthetic polymers means that in many studies only a small parameter range can be realistically synthesized in a short time and hence the “best” formulations may not be optimum. Throughput is traditionally limited by the need for deoxygenation in radical polymerizations, but advances in photopolymerization now provide opportunities for “in-air” polymerizations. Here, we have developed a protocol using liquid handling robots (or multichannel pipettes) with blue light photolysis of reversible addition fragmentation chain transfer agents and tertiary amine deoxygenation to enable the synthesis of polymer libraries in industry-standard 96-well plates with no specialized infrastructure and no degassing step. The roles of solvents and amine deoxygenators are explored to optimize the polymerization, particularly to look at alternatives to dimethyl sulfoxide (DMSO) for hydrophobic monomer (co)polymerization. DMSO is shown to aid the degassing process but is not easy to remove and hence prevents isolation of pure polymers. In contrast, using dioxane in-plate evaporation or precipitation of the tertiary amine allowed isolation of polymers in-plate. This removed all reaction components yielding pure polymers, which is not easily achieved with systems using metal catalysts and secondary reductants, such as ascorbic acid. As an example of the throughput, in just under 40 h, 392 polymers were synthesized and subsequently analyzed direct from plates by a 96-well plate sampling size exclusion chromatography system to demonstrate reproducibility. Due to less efficient degassing in dioxane (compared to DMSO), the molecular weight and dispersity control were limited in some cases (with acrylates giving the lowest dispersities), but the key aim of this system is to access hundreds of polymers quickly and in a format needed to enable testing. This method enables easy exploration of chemical space and development of screening libraries to identify hits for further study using precision polymerization methods
Nature and occurrence of trichomes in sorghum lines with resistance to the sorghum shootfly
The sorghum shootfly (Atherigona soccata Rond.) is a major pest of sorghum (Sorghum bicolor Moench) in much of the Indian subcontinent and in many parts of Africa..
Double differentiation in a cross-national comparison of populist political movements and online media uses in the United States and the Netherlands
In a context of highly visible and politically influential populist movements, this study considers the online self-representation of the Tea Party Patriots (TPP) in the United States and the Party for Freedom (PVV) in the Netherlands. A multi-methodological approach was adopted to compare the discursive manifestation of key populism concepts: leadership characteristics, adversary definition and mobilizing information. Analyses reconstruct and account for similarities and differences in discursive framing strategies of 'double differentiation' through which both movements attempt inclusion in and exclusion from the political establishment, and, in doing so, mobilize communities of support. Altogether, this study advances the understanding of what constitutes 'unmediated' content that is presented through user-generated media production, and how self-determined media spaces have facilitated shifts in populist media legitimation and political representation in two politically unique countries
A Redetermination of the Hubble Constant with the Hubble Space Telescope from a Differential Distance Ladder
We report observations of 240 Cepheid variables obtained with the Near
Infrared Camera (NICMOS) through the F160W filter on the Hubble Space Telescope
(HST). The Cepheids are distributed across six recent hosts of Type Ia
supernovae (SNe Ia) and the "maser galaxy" NGC 4258, allowing us to directly
calibrate the peak luminosities of the SNe Ia from the precise, geometric
distance measurements provided by the masers. New features of our measurement
include the use of the same instrument for all Cepheid measurements across the
distance ladder and homogeneity of the Cepheid periods and metallicities thus
necessitating only a differential measurement of Cepheid fluxes and reducing
the largest systematic uncertainties in the determination of the fiducial SN Ia
luminosity. The NICMOS measurements reduce differential extinction in the host
galaxies by a factor of 5 over past optical data. Combined with an expanded of
240 SNe Ia at z<0.1 which define their magnitude-redshift relation, we find
H_0=74.2 +/-3.6, a 4.8% uncertainty including both statistical and systematic
errors. We show that the factor of 2.2 improvement in the precision of H_0 is a
significant aid to the determination of the equation-of-state of dark energy, w
= P/(rho c^2). Combined with the WMAP 5-year measurement of Omega_M h^2, we
find w= -1.12 +/- 0.12 independent of high-redshift SNe Ia or baryon acoustic
oscillations (BAO). This result is also consistent with analyses based on the
combination of high-z SNe Ia and BAO. The constraints on w(z) now with high-z
SNe Ia and BAO are consistent with a cosmological constant and improved by a
factor of 3 from the refinement in H_0 alone. We show future improvements in
H_0 are likely and will further contribute to multi-technique studies of dark
energy.Comment: 60 pages, 15 figures Accepted for Publication, ApJ. This is the
second of two papers reporting results from a program to determine the Hubble
constant to 5% precision from a refurbished distance ladder based on
extensive use of differential measurement
The impact of music festival attendance on young people's psychological and social well being
Although the social, emotional, physical and cognitive benefits of engagement in music are well known, little research has been conducted on the psychological benefits of music in the context of music festivals. This article draws on theoretical constructs from the field of positive psychology to interpret the impact of music festival attendance on participants' psychological and social well-being. Qualitative and quantitative data were collected from a focus group and questionnaire survey with young festival-goers aged 18-29 years. Four facets of the music festival experience were identified that were associated with well-being outcomes. These are explored and discussed with reference both to participants' focus group comments and statistical analysis of questionnaire responses. A conceptual model is presented in order to guide further research in this area, and enable both festival organizers and attendees to take optimal advantage of the potential of music festivals to impact positively on young adults' psychological and social well-being
The pros and cons of the inversion method approach to derive 3D dust emission properties in the ISM: the Hi-GAL field centred on (l, b) = (30°, 0°)
Herschel far-infrared continuum data obtained as part of the Hi-GAL survey have been used, together with the GLIMPSE 8 μm and MIPSGAL 24 μm data, to attempt the first 3D-decomposition of dust emission associated with atomic, molecular and ionized gas at 15 arcmin angular resolution. Our initial test case is a 2 × 2 square degrees region centred on (l, b) = (30°, 0°), a direction that encompasses the origin point of the Scutum–Crux Arm at the tip of the Galactic Bar. Coupling the IR maps with velocity maps specific for different gas phases (H i 21cm, ^(12)CO and ^(13)CO, and radio recombination lines), we estimate the properties of dust blended with each of the gas components and at different Galactocentric distances along the line of sight (LOS). A statistical Pearson's coefficients analysis is used to study the correlation between the column densities estimated for each gas component and the intensity of the IR emission. This analysis provides evidence that the 2 × 2 square degree field under consideration is characterized by the presence of a gas component not accounted for by the standard tracers, possibly associated with warm H_2 and cold H I. We demonstrate that the IR radiation in the range 8 < λ < 500 μm is systematically dominated by emission originating within the Scutum–Crux Arm. By applying an inversion method, we recover the dust emissivities associated with atomic, molecular and ionized gas. Using the DustEM model, we fit the spectral energy distributions for each gas phase, and find average dust temperatures of T_(d,H I) = 18.82 ± 0.47 K, T_(d,H_2) = 18.84 ± 1.06 K and T_(d,H II) = 22.56 ± 0.64 K, respectively. We also obtain an indication for polycyclic aromatic hydrocarbons depletion in the diffuse ionized gas. We demonstrate the importance of including the ionized component in 3D-decompositions of the total IR emission. However, the main goal of this work is to discuss the impact of the missing column density associated with the dark gas component on the accurate evaluation of the dust properties, and to shed light on the limitations of the inversion method approach when this is applied to a small section of the Galactic plane and when the working resolution allows sufficient de-blending of the gas components along the LOS
Transnational reflections on transnational research projects on men, boys and gender relations
This article reflects on the research project, ‘Engaging South African and Finnish youth towards new traditions of non-violence, equality and social well-being’, funded by the Finnish and South African national research councils, in the context of wider debates on research, projects and transnational processes. The project is located within a broader analysis of research projects and projectization (the reduction of research to separate projects), and the increasing tendencies for research to be framed within and as projects, with their own specific temporal and organizational characteristics. This approach is developed further in terms of different understandings of research across borders: international, comparative, multinational and transnational. Special attention is given to differences between research projects that are in the Europe and the EU, and projects that are between the global North and the global South. The theoretical, political and practical challenges of the North-South research project are discussed
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