7,353 research outputs found
IT service management: towards a contingency theory of performance measurement
Information Technology Service Management (ITSM) focuses on IT service creation, design, delivery and maintenance. Measurement is one of the basic underlying elements of service science and this paper contributes to service science by focussing on the selection of performance metrics for ITSM. Contingency theory is used to provide a theoretical foundation for the study. Content analysis of interviews of ITSM managers at six organisations revealed that selection of metrics is influenced by a discrete set of factors. Three categories of factors were identified: external environment, parent organisationand IS organisation. For individual cases, selection of metrics was contingent on factors such as organisation culture, management philosophy and perspectives, legislation, industry sector, and customers, although a common set of four factors influenced selection of metrics across all organisations. A strong link was identified between the use of a corporate performance framework and clearly articulated ITSM metrics
Effectiveness of online, school-based Positive Psychology Interventions to improve mental health and wellbeing: A systematic review
Online positive psychology interventions provide a more equitable method for young people to access wellbeing education at school than more traditional face to face programs. This systematic review aimed to examine the effectiveness of universal, online, school-based, positive psychology interventions using recommendations by the Preferred Reporting Items for Systematic reviews and Meta-analyses - protocols (PRISMA-P). Nine articles were identified for the review and were deductively, thematically analyzed using an enhanced RE-AIM framework which adopts a wider systems perspective including evaluation of socio-ecological readiness system wide buy-in and consideration of micro (individual) to macro (governing bodies) levels of influence, on both reach and adoption. Effectiveness assessment identified common factors for success related primarily to implementation (e.g., readiness, reach, outcomes, adoption, implementation, and maintenance). For example, buy-in from stakeholders was found to be highest when PPIs are age appropriate, engaging and helpful. Also brief, more frequent sessions, may be more effective than less frequent longer sessions and multi-level stakeholder buy-in may result in higher completion rates leading to better overall program effectiveness
Electric Field Measurement of Femtosecond Time-Resolved Four-Wave Mixing Signals in Molecules
We report an experiment to measure the femtosecond electric field of the
signal emitted from an optical third-order nonlinear interaction in carbon
dioxide molecules. Using degenerate four-wave mixing with femtosecond near
infrared laser pulses in combination with the ultra-weak femtosecond pulse
measurement technique of TADPOLE, we measure the nonlinear signal electric
field in the time domain at different time delays between the interacting
pulses. The chirp extracted from the temporal phase of the emitted nonlinear
signal is found to sensitively depend on the electronic and rotational
contributions to the nonlinear response. While the rotational contribution
results in a nonlinear signal chirp close to the chirp of the input pulses, the
electronic contribution results in a significantly higher chirp which changes
with time delay. Our work demonstrates that electric field-resolved nonlinear
spectroscopy offers detailed information on nonlinear interactions at ultrafast
time scales.Comment: 8 pages, 4 figures, and supplemental documen
A novel strategy for the targeted analysis of protein and peptide metabolites
The detection and quantitation of exogenously administered biological macromolecules (e.g. vaccines, peptide and protein therapeutics) and their metabolites is frequently complicated by the presence of a complex endogenous mixture of closely related compounds. We describe a method that incorporates stable isotope labeling of the compound of interest allowing the selective screening of the intact molecule and all metabolites using a modified precursor ion scan. This method involves monitoring the low molecular weight fragment ions produced during MS/MS that distinguish isotopically labelled material from related endogenous compounds. All isotopically labelled substances can be selected using this scanning technique for further analysis whilst other unlabelled and irrelevant substances are ignored. The potential for this technique to be used in metabolism and pharmacokinetic experiments is discussed with specific examples looking at the metabolism of α-synuclein in serum and the brain
Ultrafast Field-Resolved Nonlinear Optical Spectroscopy in the Molecular Frame
We resolve the real-time electric field of a femtosecond third-order
nonlinear optical signal in the molecular frame. The electric field emitted by
the induced third-order polarization from impulsively pre-aligned gas-phase
molecules at room temperature, in a degenerate four-wave mixing (DFWM) scheme,
is measured using a spectral interferometry technique. We show that by
measuring both the amplitude and phase of the emitted femtosecond pulse,
information related to electronic symmetries can be accessed. The nonlinear
signal is measured around a rotational revival to extract its molecular-frame
angle dependence from pump-probe time delay scans. By comparing these
measurements for two linear molecules, carbon dioxide (CO2) and Nitrogen (N2),
we show that the measured second-order phase parameter (temporal chirp) of the
signal is sensitive to the valence electronic symmetry of the molecules,
whereas the amplitude of the signal does not show such sensitivity. We compare
these measurements to theoretical calculations of the chirp observable in the
molecular frame. This work is an important step towards using field-resolved
nonlinear optical measurements to study ultrafast dynamics in electronically
excited molecules.Comment: 10 pages, 3 figures and 1 supplemental documen
Serotonin and serotonin receptors in neural stem and progenitor cell proliferation
Ph.DDOCTOR OF PHILOSOPH
Aqueous Angiography with Fluorescein and Indocyanine Green in Bovine Eyes.
PurposeWe characterize aqueous angiography as a real-time aqueous humor outflow imaging (AHO) modality in cow eyes with two tracers of different molecular characteristics.MethodsCow enucleated eyes (n = 31) were obtained and perfused with balanced salt solution via a Lewicky AC maintainer through a 1-mm side-port. Fluorescein (2.5%) or indocyanine green (ICG; 0.4%) were introduced intracamerally at 10 mm Hg individually or sequentially. With an angiographer, infrared and fluorescent images were acquired. Concurrent anterior segment optical coherence tomography (OCT) was performed, and fixable fluorescent dextrans were introduced into the eye for histologic analysis of angiographically positive and negative areas.ResultsAqueous angiography in cow eyes with fluorescein and ICG yielded high-quality images with segmental patterns. Over time, ICG maintained a better intraluminal presence. Angiographically positive, but not negative, areas demonstrated intrascleral lumens with anterior segment OCT. Aqueous angiography with fluorescent dextrans led to their trapping in AHO pathways. Sequential aqueous angiography with ICG followed by fluorescein in cow eyes demonstrated similar patterns.ConclusionsAqueous angiography in model cow eyes demonstrated segmental angiographic outflow patterns with either fluorescein or ICG as a tracer.Translational relevanceFurther characterization of segmental AHO with aqueous angiography may allow for intelligent placement of trabecular bypass minimally invasive glaucoma surgeries for improved surgical results
- …