5,001 research outputs found
Research 2.0 : improving participation in online research communities
Web 2.0 thinking and technologies create a number of new opportunities to conduct research broadly labeled as Research 2.0. Research 2.0 is a growing area of academic and commercial interest, which includes research undertaken in online research communities. This research in progress paper explores the practice of online research communities using a case study example operated by the commercial market research company Virtual Surveys Limited (VSL) in the UK on behalf of their client United Biscuits UK Ltd.
The preliminary findings are based on VSL and academics working together to improve the online research community participantsâ response rate and the quality of contributions. Data collected for this study is based on meetings, participant observation, and a pilot survey of United Biscuits online research community (snackrs.com) members.
Using the responses of 112 snackrs.com community members, a preliminary typology of motivational factors is proposed. This can be used to refine the recruitment and development of activities in an online research community. Also, a model for supporting online research communities to ensure longitudinal engagement based on an adaptation of Salmonâs (2004) 5 Stage Model for e-moderation is proposed, extending the 5 stages to 7 â adding the stages of selection and disengagemen
The quality of different types of child care at 10 and 18 months. A comparison between types and factors related to quality.
The quality of care offered in four different types of non-parental child care to 307 infants at 10 months old and 331 infants at 18 months old was compared and factors associated with higher quality were identified. Observed quality was lowest in nurseries at each age point, except that at 18 months they offered more learning activities. There were few differences in the observed quality of care by child-minders, grandparents and nannies, although grandparents had somewhat lower safety and health scores and offered children fewer activities. Cost was largely unrelated to quality of care except in child-minding, where higher cost was associated with higher quality. Observed ratios of children to adults had a significant impact on quality of nursery care; the more infants or toddlers each adult had to care for, the lower the quality of the care she gave them. Mothers' overall satisfaction with their child's care was positively associated with its quality for home-based care but not for nursery settings
Curve crossing in linear potential grids: the quasidegeneracy approximation
The quasidegeneracy approximation [V. A. Yurovsky, A. Ben-Reuven, P. S.
Julienne, and Y. B. Band, J. Phys. B {\bf 32}, 1845 (1999)] is used here to
evaluate transition amplitudes for the problem of curve crossing in linear
potential grids involving two sets of parallel potentials. The approximation
describes phenomena, such as counterintuitive transitions and saturation
(incomplete population transfer), not predictable by the assumption of
independent crossings. Also, a new kind of oscillations due to quantum
interference (different from the well-known St\"uckelberg oscillations) is
disclosed, and its nature discussed. The approximation can find applications in
many fields of physics, where multistate curve crossing problems occur.Comment: LaTeX, 8 pages, 8 PostScript figures, uses REVTeX and psfig,
submitted to Physical Review
Counterintuitive transitions in multistate curve crossing involving linear potentials
Two problems incorporating a set of horizontal linear potentials crossed by a
sloped linear potential are analytically solved and compared with numerical
results: (a) the case where boundary conditions are specified at the ends of a
finite interval, and (b) the case where the sloped linear potential is replaced
by a piecewise-linear sloped potential and the boundary conditions are
specified at infinity. In the approximation of small gaps between the
horizontal potentials, an approach similar to the one used for the degenerate
problem (Yurovsky V A and Ben-Reuven A 1998 J. Phys. B 31,1) is applicable for
both problems. The resulting scattering matrix has a form different from the
semiclassical result obtained by taking the product of Landau-Zener amplitudes.
Counterintuitive transitions involving a pair of successive crossings, in which
the second crossing precedes the first one along the direction of motion, are
allowed in both models considered here.Comment: LaTeX 2.09 using ioplppt.sty and psfig.sty, 16 pages with 5 figures.
Submitted to J. Phys.
Ideal participants in online market research: Lessons from closed communities
Online market research communities are dependent upon their membersâ participation that in turn provides market intelligence for community operators. However, people join these communities for different reasons. The selection process for market research community members and the moderation process of these communities have a number of pitfalls, which can result in misleading interpretations of intelligence and flawed decisions based on their contributions.
Using social capital theory in conjunction with research on different motivational types of participants, this paper focuses on lessons from commercially operated, closed online market research communities; it provides us with insights on membership selection and community moderation methods.
The practical finding is that the ideal participant of such communities would be attracted by activities and rewards, which do not directly or obviously relate to the specific objective of an online market research community
Counterintuitive transitions between crossing energy levels
We calculate analytically the probabilities for intuitive and
counterintuitive transitions in a three-state system, in which two parallel
energies are crossed by a third, tilted energy. The state with the tilted
energy is coupled to the other two states in a chainwise linkage pattern with
constant couplings of finite duration. The probability for a counterintuitive
transition is found to increase with the square of the coupling and decrease
with the squares of the interaction duration, the energy splitting between the
parallel energies, and the tilt (chirp) rate. Physical examples of this model
can be found in coherent atomic excitation and optical shielding in cold atomic
collisions
Accumulation of plutonium in mammalian wildlife tissues: comparison of recent data with the ICRP distribution models
We examined the distribution of plutonium (Pu) in the tissues of mammalian wildlife to address the paucity of such data under environmental exposure conditions. Pu activity concentrations were measured in Macropus rufus (red kangaroo), Oryctolagus cuniculus (European rabbit), and Pseudomys hermannsburgensis (sandy inland mouse)inhabiting the relatively undisturbed, semi-arid conditions at the former Taranaki weapons test site at Maralinga, Australia. Of the absorbed Pu (distributed via circulatory and lymph systems) accumulation was foremost in bone (83% ±10% SD), followed by muscle (9% ±10%), liver (7% ±7%), kidneys (0.5% ±0.3%), and heart (0.4% ±0.4%). The bone values are higher than those reported in ICRP 19 and 48 (45-50% bone), while the liver values are lower than ICRP values (30-45% liver). The ICRP values were based on data dominated by relatively soluble forms of Pu, including prepared solutions and single-atom ions produced by decay following the volatilisation of uranium during nuclear detonation (fallout Pu, ICRP 1986). In contrast, the Maralinga data relates to low-soluble forms of Pu used in tests designed to simulate accidental release and dispersal. We measured Pu in lung, GI-tract and the skin and fur as distinct from the absorbed Pu in bone, liver, muscle, and kidneys. Compared with the mean absorbed activity concentrations, the results for lung tissues were higher by up to one order of magnitude, and those in the GI tract contents and the washed skin/fur were higher by more than two orders of magnitude. These elevated levels are consistent with the presence of low-soluble Pu, including particulate forms, which pass through, or adhere upon, certain organs, but are not readily absorbed into the bloodstream. This more transitory Pu can provide dose to the lung and GI tract organs, as well as provide potential transfer of contamination when consumed in predator-prey food chains, or during human foodstuff consumption. For example, activity concentrations in O. cuniculus edible samples prepared according to traditional aboriginal methods were more than two orders of magnitude higher than in muscle alone. The increase was due to inclusion of GI tract components and contents in the traditional method. Our results provide new insights into the sequestration of Pu in mammalian tissues under environmental exposure conditions. These results contrast with those related to the specific forms of Pu and exposure conditions upon which the ICRP models were based. However, they provide data relevant to the assessment of key environmental legacy waste sites, and of potential release scenarios for the low-soluble oxide forms in the growing worldwide inventory of Pu associated with power production
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