2,967 research outputs found
On the transition to dripping of an inverted liquid film
The transition to dripping in the gravity-driven flow of a liquid film under
an inclined plate is investigated at zero Reynolds number. Computations are
carried out on a periodic domain assuming either a fixed fluid volume or a
fixed flow rate for a hierarchy of models: two lubrication models with either
linearised curvature or full curvature (the LCM and FCM, respectively), and the
full equations of Stokes flow. Of particular interest is the breakdown of
travelling-wave solutions as the plate inclination angle is increased. For any
fixed volume the LCM reaches the horizontal state where it attains a
cosine-shaped profile. For sufficiently small volume, the FCM and Stokes
solutions attain a weak Young-Laplace equilibrium profile, the approach to
which is described by an asymptotic analysis generalising that of Kalliadasis &
Chang (1994) for the LCM. For large volumes, the bifurcation curves for the FCM
and Stokes model have a turning point so that the fully inverted state is never
reached. For fixed flow rate the LCM blows up at a critical angle that is well
predicted by asymptotic analysis. The bifurcation curve for the FCM either has
a turning point or else reaches a point at which the surface profile has an
infinite slope singularity, indicating the onset of multi-valuedness. The
latter is confirmed by the Stokes model which can be continued to obtain
overturning surface profiles. Overall the thin-film models either provide an
accurate prediction for dripping onset or else supply an upper bound on the
critical inclination angle
A cohort study of influences, health outcomes and costs of patients' health-seeking behaviour for minor ailments from primary and emergency care settings
To compare health-related and cost-related outcomes of consultations for symptoms suggestive of minor ailments in emergency departments (EDs), general practices and community pharmacies
Recommended from our members
Flow-induced dynamic surface tension effects at nanoscale
The aim of this study is to investigate flow-induced dynamic surface tension effects, similar to the well-known Marangoni phenomena, but solely generated by the nanoscale topography of the substrates. The flow-induced surface tension effects are examined on the basis of a sharp interface theory. It is demonstrated how nanoscale objects placed at the boundary of the flow domain result in the generation of substantial surface forces acting on the bulk flow
Excitation functions of baryon anomaly and freeze-out properties at RHIC-PHENIX
The intermediate region (2 - 5 GeV/) in central Au+Au collisions at
RHIC has a rich physics content. The (anti)proton to pion ratio at the
intermediate gives us a powerful tool to investigate the bulk properties
of the hot and dense matter created at RHIC and their hadronization processes.
We present the preliminary results of identified charged hadron spectra at the
lower beam energies at RHIC. The excitation function of (anti)proton to pion
ratios from SPS to RHIC are shown. We also discuss the onset of the baryon
enhancement at the high energy heavy ion collisions.Comment: 4 pages, 3 figures, Quark Matter 2006 conference proceeding
Voluntary DNA-based information exchange and contact services following donor conception: an analysis of service usersâ needs
Medical science has enabled the creation of families through the use of donor conception but some lifelong policy and practice implications are only recently being recognized. Research and practice have shown that donor conception can, for some, carry substantial long-term consequences. In this paper we present findings from a questionnaire-based study that sought to shed light on donor-conceived adultsâ and gamete donorsâ views on service and support needs when searching for genetic relatives with the aid of DNA testing. The findings demonstrate the complexity and sensitivity of providing services in this newly emerging area of need. Such provision requires collaboration between very different disciplines and agencies (scientific and psychosocial), introduces the potential for blurring of lines of accountability and responsibility, and highlights the challenges of identifying appropriate funding streams. In addition, the findings demonstrate the opportunities and limitations afforded by the use of DNA in identifying unknown genetic relatives
Quantum Cosmology in Scalar-Tensor Theories With Non Minimal Coupling
Quantization in the minisuperspace of non minimal scalar-tensor theories
leads to a partial differential equation which is non separable. Through a
conformal transformation we can recast the Wheeler-DeWitt equation in an
integrable form, which corresponds to the minimal coupling case, whose general
solution is known. Performing the inverse conformal transformation in the
solution so found, we can construct the corresponding one in the original
frame. This procedure can also be employed with the bohmian trajectories. In
this way, we can study the classical limit of some solutions of this quantum
model. While the classical limit of these solutions occurs for small scale
factors in the Einstein's frame, it happens for small values of the scalar
field non minimally coupled to gravity in the Jordan's frame, which includes
large scale factors.Comment: latex, 18 page
Search for the h_c meson in B^+- ->h_c K^+-
We report a search for the meson via the decay chain , \etac \gamma with and
. No significant signals are observed. We obtain upper limits on the
branching fractions for in bins of the
invariant mass. The results are based on an analysis of 253
fb of data collected by the Belle detector at the KEKB
collider.Comment: 12 pages, 6 figures, submitted to Phys. Rev.
QCD corrections to the forward-backward asymmetries of and quarks at the Z pole
Measurements of the forward-backward production asymmetry of heavy quarks in Z decays provide a precise determination of \swsqeffl . The asymmetries are sensitive to QCD effects, in particular hard gluon radiation. In this paper QCD corrections for \AFBbb~ and \AFBcc~ are discussed. The interplay between the experimental techniques used to measure the asymmetries and the QCD effects is investigated using simulated events. A procedure to estimate the correction needed for experimental measurements is proposed, and some specific examples are given
Recommended from our members
Microphysical properties of cold frontal rainbands
Observations have been obtained within an intense (precipitation rates > 50 mm hâ1 ) narrow cold-frontal rainband (NCFR) embedded within a broader region of stratiform precipitation. In situ data were obtained from an aircraft which ïŹew near a steerable dual-polarisation Doppler radar. The observations were obtained to characterise the microphysical properties of cold frontal clouds, with an emphasis on ice and precipitation formation and development. Primary ice nucleation near cloud top (â55⊠C) appeared to be enhanced by convective
features. However, ice multiplication led to the largest ice particle number concentrations being observed at relatively high temperatures (> â10⊠C). The multiplication process (most likely rime splintering) occurs when stratiform precipitation interacts with supercooled water generated in the NCFR. Graupel was notably absent in the data obtained. Ice multiplication processes are known to have a strong impact in glaciating isolated convective clouds, but have rarely been studied within larger organised convective systems such as NCFRs. Secondary ice particles will impact on precipitation formation and cloud dynamics due to their relatively small size and high number density. Further modelling
studies are required to quantify the effects of rime splintering on precipitation and dynamics in frontal rainbands. Available parametrizations used to diagnose the particle size distributions do not account for the inïŹuence of ice multiplication. This deïŹciency in parametrizations is likely to be important in some cases for modelling the evolution of cloud systems and the precipitation formation. Ice multiplication has signiïŹcant impact on artefact removal from in situ particle imaging probes
Recommended from our members
Dialectic tensions in the financial markets: a longitudinal study of pre- and post-crisis regulatory technology
This article presents the findings from a longitudinal research study on regulatory technology in the UK financial services industry. The financial crisis with serious corporate and mutual fund scandals raised the profile of
compliance as governmental bodies, institutional and private investors introduced a âtsunamiâ of financial regulations. Adopting a multi-level analysis, this study examines how regulatory technology was used by financial firms to meet their compliance obligations, pre- and post-crisis. Empirical data collected over 12 years examine the deployment of
an investment management system in eight financial firms. Interviews with public regulatory bodies, financial
institutions and technology providers reveal a culture of compliance with increased transparency, surveillance and
accountability. Findings show that dialectic tensions arise as the pursuit of transparency, surveillance and
accountability in compliance mandates is simultaneously rationalized, facilitated and obscured by regulatory
technology. Responding to these challenges, regulatory bodies continue to impose revised compliance mandates on
financial firms to force them to adapt their financial technologies in an ever-changing multi-jurisdictional regulatory landscape
- âŠ