1,261 research outputs found
GraFIX: a semiautomatic approach for parsing low- and high-quality eye-tracking data
Fixation durations (FD) have been used widely as a measurement of information processing and attention. However, issues like data quality can seriously influence the accuracy of the fixation detection methods and, thus, affect the validity of our results (Holmqvist, Nyström, & Mulvey, 2012). This is crucial when studying special populations such as infants, where common issues with testing (e.g., high degree of movement, unreliable eye detection, low spatial precision) result in highly variable data quality and render existing FD detection approaches highly time consuming (hand-coding) or imprecise (automatic detection). To address this problem, we present GraFIX, a novel semiautomatic method consisting of a two-step process in which eye-tracking data is initially parsed by using velocity-based algorithms whose input parameters are adapted by the user and then manipulated using the graphical interface, allowing accurate and rapid adjustments of the algorithms’ outcome. The present algorithms (1) smooth the raw data, (2) interpolate missing data points, and (3) apply a number of criteria to automatically evaluate and remove artifactual fixations. The input parameters (e.g., velocity threshold, interpolation latency) can be easily manually adapted to fit each participant. Furthermore, the present application includes visualization tools that facilitate the manual coding of fixations. We assessed this method by performing an intercoder reliability analysis in two groups of infants presenting low- and high-quality data and compared it with previous methods. Results revealed that our two-step approach with adaptable FD detection criteria gives rise to more reliable and stable measures in low- and high-quality data
Non-Perturbative String Equations for Type 0A
Well-defined non-perturbative formulations of the physics of string theories,
sometimes with D-branes present, were identified over a decade ago, from a
careful study of double scaled matrix models. Following recent work which
recasts some of those old results in the context of type 0 string theory, a
study is made of a much larger family of models, which are proposed as type 0A
models of the entire superconformal minimal series coupled to gravity. This
gives many further examples of important physical phenomena, including
non-perturbative descriptions of transitions between D-branes and fluxes,
tachyon condensation, and holography. In particular, features of a large family
of non-perturbatively stable string equations are studied, and results are
extracted which pertain to type 0A string theory, with D-branes and fluxes, in
this large class of backgrounds. For the entire construction to work, large
parts of the spectrum of the supergravitationally dressed superconformal
minimal models and that of the gravitationally dressed bosonic conformal
minimal models must coincide, and it is shown how this happens. The example of
the super-dressed tricritical Ising model is studied in some detail.Comment: 29 pages LaTe
Antithrombotic therapy in palliative care
Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the
increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or
exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight
heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications
to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux
may have a role in the future.Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the
increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or
exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight
heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications
to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux
may have a role in the future
Annulus Amplitudes in the Minimal Superstring
We study the annulus amplitudes in the (2,4) minimal superstring theory using
the continuum worldsheet approach. Our results reproduce the semiclassical
behavior of the wavefunctions of FZZT-branes recently studied in hep-th/0412315
using the dual matrix model. We also study the multi-point functions of neutral
FZZT-branes and find the agreement between their semiclassical limit and the
worldsheet annulus calculation.Comment: 15 pages, lanlma
Canine mesenchymal stem cells are neurotrophic and angiogenic:an in vitro assessment of their paracrine activity
Mesenchymal stem cells (MSCs) have been used in cell replacement therapies for connective tissue damage, but also can stimulate wound healing through paracrine activity. In order to further understand the potential use of MSCs to treat dogs with neurological disorders, this study examined the paracrine action of adipose-derived canine MSCs on neuronal and endothelial cell models. The culture-expanded MSCs exhibited a MSC phenotype according to plastic adherence, cell morphology, CD profiling and differentiation potential along mesenchymal lineages. Treating the SH-SY5Y neuronal cell line with serum-free MSC culture-conditioned medium (MSC CM) significantly increased SH-SY5Y cell proliferation (P < 0.01), neurite outgrowth (P = 0.0055) and immunopositivity for the neuronal marker βIII-tubulin (P = 0.0002). Treatment of the EA.hy926 endothelial cell line with MSC CM significantly increased the rate of wound closure in endothelial cell scratch wound assays (P = 0.0409), which was associated with significantly increased endothelial cell proliferation (P < 0.05) and migration (P = 0.0001). Furthermore, canine MSC CM induced endothelial tubule formation in EA.hy926 cells in a soluble basement membrane matrix. Hence, this study has demonstrated that adipose-derived canine MSC CM stimulated neuronal and endothelial cells probably through the paracrine activity of MSC-secreted factors. This supports the use of canine MSC transplants or their secreted products in the clinical treatment of dogs with neurological disorders and provides some insight into possible mechanisms of action
Tachyon Condensation, Open-Closed Duality, Resolvents, and Minimal Bosonic and Type 0 Strings
Type 0A string theory in the (2,4k) superconformal minimal model backgrounds
and the bosonic string in the (2,2k-1) conformal minimal models, while
perturbatively identical in some regimes, may be distinguished
non-perturbatively using double scaled matrix models. The resolvent of an
associated Schrodinger operator plays three very important interconnected
roles, which we explore perturbatively and non-perturbatively. On one hand, it
acts as a source for placing D-branes and fluxes into the background, while on
the other, it acts as a probe of the background, its first integral yielding
the effective force on a scaled eigenvalue. We study this probe at disc, torus
and annulus order in perturbation theory, in order to characterize the effects
of D-branes and fluxes on the matrix eigenvalues. On a third hand, the
integrated resolvent forms a representation of a twisted boson in an associated
conformal field theory. The entire content of the closed string theory can be
expressed in terms of Virasoro constraints on the partition function, which is
realized as wavefunction in a coherent state of the boson. Remarkably, the
D-brane or flux background is simply prepared by acting with a vertex operator
of the twisted boson. This generates a number of sharp examples of open-closed
duality, both old and new. We discuss whether the twisted boson conformal field
theory can usefully be thought of as another holographic dual of the
non-critical string theory.Comment: 37 pages, some figures, LaTe
Leczenie przeciwzakrzepowe w opiece paliatywnej
Postępowanie w przypadku choroby zakrzepowo-zatorowej (VTE) u pacjentów z zaawansowaną chorobą
nowotworową może być trudne ze względu na zwiększone ryzyko nawracających i szerzących się powikłań
zakrzepowo-zatorowych, które występują mimo stosowanego leczenia przeciwkrzepliwego, oraz krwawienia
mogącego występować lub nasilać się pod wpływem leków przeciwzakrzepowych. Obecnie najlepszą praktyką
jest długotrwałe stosowanie heparyny niskocząsteczkowej (LMWH), ale nadal aktualny jest problem
nawrotów VTE i krwawień; ponadto u niektórych pacjentów leczenie przeciwzakrzepowe jest przeciwwskazane.
W przyszłości istotne znaczenie mogą mieć nowsze leku przeciwzakrzepowe, takie jak doustne inhibitory
trombiny i biotynylowany idraparynuks.
Medycyna Paliatywna w Praktyce 2010; 4, 2: 74-8
- …