2,833 research outputs found
Temperature-tuning of near-infrared monodisperse quantum dot solids at 1.5 um for controllable Forster energy transfer
We present the first time-resolved cryogenic observations of Forster energy
transfer in large, monodisperse lead sulphide quantum dots with ground state
transitions near 1.5 um (0.83 eV), in environments from 160 K to room
temperature. The observed temperature-dependent dipole-dipole transfer rate
occurs in the range of (30-50 ns)^(-1), measured with our confocal
single-photon counting setup at 1.5 um wavelengths. By temperature-tuning the
dots, 94% efficiency of resonant energy transfer can be achieved for donor
dots. The resonant transfer rates match well with proposed theoretical models
META-ANALYSIS OF MEDICAL AND NON-MEDICAL TREATMENTS OF THE PRODROMAL PHASE OF PSYCHOTIC ILLNESS IN AT-RISK MENTAL STATES
Introduction: There are now many existing studies which assess the treatments available for âat risk mental statesâ, as patients
who are believed to be in the prodromal phase of psychotic illness are referred to. However, concerns regarding side effects of
possible treatments remain.
We here conduct a meta-analysis of the studies available up to October 2010. The aim of this study is to decide what would be
the best treatment for âat high risk patientsâ.
Results: All the available studies examining potential treatments during the prodromal phase of psychotic illness were collected.
They all showed comparable efficacy, which reached statistical significance, excluding the one study using olanzapine, which in fact
âtended towards significanceâ.
Discussion: Treatments appear promising but a balance needs to be kept between adverse events and effectiveness of preventing
psychosis.
Conclusion: It is necessary to search further for treatments in order to identify effective treatments with fewer adverse side
effects in this phase of psychotic illness
AN UPDATE ON: META-ANALYSIS OF MEDICAL AND NON-MEDICALTREATMENTS OF THE PRODROMAL PHASE OF PSYCHOTIC ILLNESS IN AT RISK MENTAL STATES
Introduction: There are now many existing studies which assess the treatments available for âat risk mental statesâ, as patients
who are believed to be in the prodromal phase of psychotic illness are referred to. However, concerns regarding side effects of
possible treatments remain. We here conduct a meta-analysis of the studies available up to July 2016. The aim of this study is to
decide what would be the best treatment for âat high risk patientsâ.
Results: 18 studies were selected for inclusion; 12 showed significance, 5 did not and one tended towards significance. Both
antipsychotic medication and psychological intervention show mixed results with cognitive behavioral therapy and
olanzapine/amisulpride coming out on top. Omega 3 poly-unsaturated acid also shows promising and consistent results.
Discussion: Treatments appear promising but a balance needs to be kept between adverse events and effectiveness of preventing
psychosis.
Conclusion: It is necessary to search further for treatments in order to identify effective treatments with fewer adverse sideeffects
in this phase of psychotic illness
Correlation for Sessile Drop Evaporation Over a Wide Range of Drop Volatilities, Ambient Gases and Pressures
A correlation for the evaporation of sessile drops over a very broad range of conditions was developed based on measured evaporation rate data obtained for drops of acetone, methanol, and six hydrocarbons ranging from hexane to isooctane, evaporating in air, helium, argon, and krypton, over a range of ambient pressures from 96 kPa to 615 kPa. The experiments were designed to produce a large variation in the rates of diffusion and buoyancy-induced (natural) convection of the vapor phase amongst the experimental conditions. The correlation, which fits the measurements with an RMS relative error of 5.2%, is a simple equation involving conventional parameters for diffusive and convective transport and is applicable to conditions for which vapor transport limits the rate of evaporation. Application of the correlation requires knowledge of eight basic properties: the ambient pressure and temperature, the equilibrium vapor pressure of the evaporating component, the diffusion coefficient for the evaporating component in the ambient gas, the viscosity of the ambient gas, the radius of the sessile drop, and the molecular weights of the evaporating component and the ambient gas. The correlation is much easier to implement than a computational model based on the coupled conservation equations of mass, energy, and momentum for the two phases, and it offers a single mathematical expression that provides valuable insight into how the roles of diffusive and convective transport change with physical and geometrical parameters. The correlation can be a valuable tool to aid in the analyses of applications involving sessile drop evaporation and to support the validation of complex computational models.
The range of experimental conditions resulted in a large variation in the rates of diffusive and naturally convective transport of the vapor. Over the range of experimental conditions, the liquid volatility, as indicated by the equilibrium vapor pressure, was varied by a factor of 16.7, the mass diffusivity by a factor of 52.2, the density difference ratio (the impetus for natural convection) by a factor of 3,557, and the drop radius by a factor of 22. In terms of the Rayleigh number, the experimental data covers a range from 5 to 361,000. Consequently, the correlation is applicable to a very broad range of conditions. To our knowledge these evaporation rate measurements of sessile drops in gases other than air and at pressures above one atmosphere are the first to be reported in the literature
SN2013fs and SN2013fr: Exploring the circumstellar-material diversity in Type II supernovae
We present photometry and spectroscopy of SN2013fs and SN2013fr in the first
100 days post-explosion. Both objects showed transient, relatively narrow
H emission lines characteristic of SNeIIn, but later resembled normal
SNeII-P or SNeII-L, indicative of fleeting interaction with circumstellar
material (CSM). SN2013fs was discovered within 8hr of explosion. Its light
curve exhibits a plateau, with spectra revealing strong CSM interaction at
early times. It is a less luminous version of the transitional SNIIn PTF11iqb,
further demonstrating a continuum of CSM interaction intensity between SNeII-P
and IIn. It requires dense CSM within 6.510~cm of the
progenitor, from a phase of advanced pre-SN mass loss shortly before explosion.
Spectropolarimetry of SN2013fs shows little continuum polarization, but
noticeable line polarization during the plateau phase. SN2013fr morphed from a
SNIIn at early times to a SNII-L. After the first epoch its narrow lines
probably arose from host-galaxy emission, but the bright, narrow H
emission at early times may be intrinsic. As for SN2013fs, this would point to
a short-lived phase of strong CSM interaction if proven to be intrinsic,
suggesting a continuum between SNeIIn and II-L. It is a low-velocity SNII-L,
like SN2009kr but more luminous. SN2013fr also developed an IR excess at later
times, due to warm CSM dust that require a more sustained phase of strong
pre-SN mass loss.Comment: MNRAS accepted. 28 pages, 23 figures, 8 table
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