78 research outputs found
Diagnosing and developing the IT skills of new entrants to higher education
This paper presents an approach to the diagnosis and development off IT skills using Computer Aided Assessment (CAA). It looks at the rationale for the assessment of IT skills and the relevance for higher education in general. It reflects on some of the outcomes of the project and staff and student thoughts on the use of CAA in this context
Energy spread of ultracold electron bunches extracted from a laser cooled gas
Ultrashort and ultracold electron bunches created by near-threshold
femtosecond photoionization of a laser-cooled gas hold great promise for
single-shot ultrafast diffraction experiments. In previous publications the
transverse beam quality and the bunch length have been determined. Here the
longitudinal energy spread of the generated bunches is measured for the first
time, using a specially developed Wien filter. The Wien filter has been
calibrated by determining the average deflection of the electron bunch as a
function of magnetic field. The measured relative energy spread
agrees well with the theoretical model
which states that it is governed by the width of the ionization laser and the
acceleration length
Descriptive Statistics for all variables.
<p>Hypomanic Personality Scale (HPS); Altman Self Rating Mania Index (ASRM); Responses to Positive Affect Scale (RPA); Positive Urgency Measure (PUM); Inspiration Scale (IS); External and Internal Scale of Inspiration (EISI).</p
Component loading table for External and Internal Inspiration Scale.
<p><i>Note: Factor</i> 1â=âSelf-focus; Factor 2â=âOthers-focus; Factor 3â=âAchievement-focus; Factor 4â=âEmotionâ=âfocus; Factor 5â=âExternal-focus h<sup>2</sup>â=âCommunality; r<sub>i(t-i)â=â</sub>Corrected item-total correlation; Corrected αâ=âCronbach's α if item delete.</p
Correlations between the EISI, EISI subscales with IS, RPA, PUM, HPS and ASRM.
<p><i>Note:</i> EISIâ=âExternal and Internal Scale of Inspiration; ISâ=âInspiration Scale; HPSâ=âHypomanic Personality Scale; ASRMâ=âAltman Self Rating Mania Index; RPAâ=âResponses to Positive Affect Scale; PUMâ=âPositive Urgency Measure; Hypothesis 1b: ** <i>p<</i>0.001 (Adjusted α-level after Bonferroni correctionâ=â0.004); Hypothesis 1c: *<i>p</i><0.002 **<i>p</i><0.001 (Adjusted α-level after Bonferroni correctionâ=â0.002); Hypothesis 2a: <i>*p</i><0.003 **<i>p<</i>0.001 (Adjusted α-level after Bonferroni correctionâ=â0.003).</p
Hypothesis 2b: Associations between HPS, ASRM, and EISI subscales.
<p>Note: EISIâ=âExternal and Internal Scale of Inspiration; HPSâ=âHypomanic Personality Scale; ASRMâ=âAltman Self Rating Mania Index. EISI, R<sup>2</sup>â=â.11** at step 1, ÎR<sup>2</sup>â=â.004 at step 2.</p><p>Self, R<sup>2</sup>â=â.10** at step 1, ÎR<sup>2</sup>â=â.004 at step 2.</p><p>Others, <i>R</i><sup>2</sup>â=â.02** at step 1, <i>ÎR</i><sup>2</sup>â=â.004 at step 2.</p><p>Achievement, <i>R</i><sup>2</sup>â=â.06** at step 1, <i>ÎR</i><sup>2</sup>â=â.001 at step 2.</p><p>Prosocial, <i>R</i><sup>2</sup>â=â.06** at step 1, <i>ÎR</i><sup>2</sup>â=â.000 at step 2.</p><p>External, <i>R</i><sup>2</sup>â=â.02** at step 1, <i>ÎR</i><sup>2</sup>â=â.002 at step 2.</p><p>*<i>p</i><0.003.</p><p>**<i>p<</i>0.001 (Adjusted α for Bonferroni correctionâ=â.003).</p
Hypothesis 2b: Associations between EISI subscales and bipolar risk, when controlling for current mania.
<p>Note: <i>R</i><sup>2</sup>â=â.11** at step 1, <i>ÎR</i><sup>2</sup>â=â.06** at step 2. HPSâ=âHypomanic Personality Scale; ASRMâ=âAltman Self-Rating Mania Scale.</p><p>**<i>p<</i>0.001 (Adjusted α for Bonferroni correctionâ=â.003).</p
External and Internal Scale of Inspiration (EISI).
<p>External and Internal Scale of Inspiration (EISI).</p
Description of Questionnaire Measures.
<p><i>Note:</i> Hypomanic Personality Scale (HPS); Altman Self Rating Mania Index (ASRM); Inspiration Scale (IS); External and Internal Scale of Inspiration (EISI); Responses to Positive Affect Scale (RPA); Positive Urgency Measure (PUM).</p
Photothermal Heating of Plasmonic Nanoantennas: Influence on Trapped Particle Dynamics and Colloid Distribution
Plasmonic
antennas are well-known and extremely powerful platforms
for optical spectroscopy, sensing, and manipulation of molecules and
nanoparticles. However, resistive antenna losses, resulting in highly
localized photothermal heat generation, may significantly compromise
their applicability. Here we investigate how the interplay between
plasmon-enhanced optical and thermal forces affects the dynamics of
nanocolloids diffusing in close proximity to gold bowtie nanoantennas.
The study is based on an anti-Stokes thermometry technique that can
measure the internal antenna temperature with an accuracy of âŒ5
K over an extended temperature range. We argue that Kapitza resistances
have a significant impact on the local thermal landscape, causing
an interface temperature discontinuity of up to âŒ20% of the
total photothermal temperature increase of the antenna studied. We
then use the bowties as plasmonic optical tweezers and quantify how
the antenna temperature influences the motion and distribution of
nearby fluorescent colloids. We find that colloidal particle motion
within the plasmonic trap is primarily dictated by a competition between
enhanced optical forces and enhanced heating, resulting in a surprising
insensitivity to the specific resonance properties of the antenna.
Furthermore, we find that thermophoretic forces inhibit diffusion
of particles toward the antenna and drive the formation of a thermal
depletion shell that extends several microns. The study highlights
the importance of thermal management at the nanoscale and points to
both neglected problems and new opportunities associated with plasmonic
photothermal effects in the context of nanoscale manipulation and
analysis
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