2,206 research outputs found
Recommended from our members
Perception of perspective in augmented reality head-up displays
Augmented Reality (AR) is emerging fast with a wide range of applications, including automotive AR Head-Up Displays (AR HUD). As a result, there is a growing need to understand human perception of depth in AR. Here, we discuss two user studies on depth perception, in particular the perspective cue. The fi rst experiment compares the perception of the perspective depth cue (1) in the physical world, (2) on a at-screen, and (3) on an AR HUD. Our AR HUD setup provided a two-dimensional vertically oriented virtual image projected at a fi xed distance. In each setting, participants were asked to estimate the size of a perspective angle. We found that the perception of angle sizes on AR HUD differs from perception in the physical world, but not from a at-screen. The
underestimation of the physical world's angle size compared to the AR HUD and screen setup might explain the egocentric depth underestimation phenomenon in virtual environments. In the second experiment, we compared perception for different graphical representations of angles that are relevant for practical
applications. Graphical alterations of angles displayed on a screen resulted in more variation between individuals' angle size estimations. Furthermore, the majority of the participants tends to underestimate the observed angle size in most conditions. Our results suggest that perspective angles on a vertically oriented fixed-depth AR HUD display mimics more accurately the perception of a screen, rather than the perception of the 3D environment. On-screen graphical alteration does not help to improve the underestimation in the majority of cases
Recurrent acute heart failure caused by sliding hiatus hernia
The case is reported of a 75 year old woman who presented with recurrent nocturnal episodes of acute pulmonary oedema. The cause was uncertain as she had normal cardiothoracic ratio on chest radiography and normal left ventricular systolic and diastolic function by transthoracic echocardiogram. Another transthoracic echocardiogram was repeated when she was recumbent for an hour and had a full stomach. It showed a striking finding of severe left atrial compression by an external structure. Computed tomography of the thorax showed an intrathoracic mass behind the left atrium causing external compression of the left atrium suggestive of a sliding hiatus hernia. Cardiac catheterisation confirmed the diagnosis by showing a pronounced rise of pulmonary capillary wedge pressure in the recumbent position compared with the sitting up position.published_or_final_versio
Gauge and Supersymmetric Invariance of a Boundary Bagger-Lambert-Gustavsson Theory
In this paper we will discuss the effect of a having a boundary on the
supersymmetric invariance and gauge invariance of the Bagger-Lambert-Gustavsson
(BLG) Theory. We will show that even though the supersymmetry and gauge
invariance of the original BLG theory is broken due to the presence of a
boundary, it restored by the addition of suitable boundary terms. In fact, to
achieve the gauge invariance of this theory, we will have to introduce new
boundary degrees of freedom. The boundary theory obeyed by these new boundary
degrees of freedom will be shown to be a generalization of the gauged
Wess-Zumino-Witten model, with the generators of the Lie algebra replaced by
the generators of the Lie 3-algebra. The gauge and supersymmetry variations of
the boundary theory will exactly cancel the boundary terms generated by the
gauge and supersymmetric variations of the bulk theory.Comment: 15 pages, 0 figures, accepted for publication in JHE
2016 Consensus statement on prevention of atherosclerotic cardiovascular disease in the Hong Kong population
published_or_final_versio
A phase II trial of ixabepilone in Asian patients with advanced gastric cancer previously treated with fluoropyrimidine-based chemotherapy
PURPOSE: The highest rates of gastric cancer occur in Eastern Asia. Fluoropyrimidine-based therapy is used initially in unresectable and metastatic disease, but no single standard of care exists following disease progression. Ixabepilone, an epothilone B analog, is a non-taxane microtubule-stabilizing agent with clinical activity across multiple tumor types approved by the United States Food and Drug Administration for treatment of metastatic breast cancer. METHODS: Asian patients with unresectable or metastatic gastric adenocarcinoma who had failed fluoropyrimidine-based chemotherapy received ixabepilone 40 mg/m(2) by 3-h intravenous infusion every 3 weeks. The primary endpoint was objective response rate (ORR). RESULTS: Fifty-two patients were treated (65.4 % men; median age: 56.5 years). The ORR was 15.4 % (95 % confidence interval [CI] 6.9-28.1); 8 patients achieved partial responses for a median duration of 3.1 months (95 % CI 2.6-4.1 months) and 26 patients (50.0 %) had stable disease. Median progression-free survival was 2.8 months (95 % CI 2.1-3.5 months). The most common grade 3 non-hematological toxicities were fatigue (9.6 %), decreased appetite (7.7 %), sensory neuropathy (5.8 %), and diarrhea (5.8 %). Grade 3/4 neutropenia occurred in 46.2 % of patients. CONCLUSIONS: Ixabepilone is active in Asian patients with advanced gastric cancer and shows a toxicity profile similar to those previously reported in other tumor types.published_or_final_versio
Isotope effect on the transition temperature in Fe-based superconductors: the current status
The results of the Fe isotope effect (Fe-IE) on the transition temperature
obtained up to date in various Fe-based high temperature superconductors
are summarized and reanalyzed by following the approach developed in [Phys.
Rev. B 82, 212505 (2010)]. It is demonstrated that the very controversial
results for Fe-IE on are caused by small structural changes occurring
simultaneously with the Fe isotope exchange. The Fe-IE exponent on
[, is the isotope mass]
needs to be decomposed into two components with the one related to the
structural changes () and the genuine (intrinsic)
one (). The validity of such decomposition is
further confirmed by the fact that coincides with
the Fe-IE exponent on the characteristic phonon frequencies as is reported in recent EXAFS and Raman experiments.Comment: 7 pages, 4 figures. The paper is partially based on the results
published in [New J. Phys. 12, 073024 (2010) = arXiv:1002.2510] and [Phys.
Rev. B 82, 212505 (2010) = arXiv:1008.4540
Anti-müllerian hormone is not associated with cardiometabolic risk factors in adolescent females
<p>Objectives: Epidemiological evidence for associations of Anti-Müllerian hormone (AMH) with cardiometabolic risk factors is lacking. Existing evidence comes from small studies in select adult populations, and findings are conflicting. We aimed to assess whether AMH is associated with cardiometabolic risk factors in a general population of adolescent females.</p>
<p>Methods: AMH, fasting insulin, glucose, HDLc, LDLc, triglycerides and C-reactive protein (CRP) were measured at a mean age 15.5 years in 1,308 female participants in the Avon Longitudinal Study of Parents and Children (ALSPAC). Multivariable linear regression was used to examine associations of AMH with these cardiometabolic outcomes.</p>
<p>Results: AMH values ranged from 0.16–35.84 ng/ml and median AMH was 3.57 ng/ml (IQR: 2.41, 5.49). For females classified as post-pubertal (n = 848) at the time of assessment median (IQR) AMH was 3.81 ng/ml (2.55, 5.82) compared with 3.25 ng/ml (2.23, 5.05) in those classed as early pubertal (n = 460, P≤0.001). After adjusting for birth weight, gestational age, pubertal stage, age, ethnicity, socioeconomic position, adiposity and use of hormonal contraceptives, there were no associations with any of the cardiometabolic outcomes. For example fasting insulin changed by 0% per doubling of AMH (95%CI: −3%,+2%) p = 0.70, with identical results if HOMA-IR was used. Results were similar after additional adjustment for smoking, physical activity and age at menarche, after exclusion of 3% of females with the highest AMH values, after excluding those that had not started menarche and after excluding those using hormonal contraceptives.</p>
<p>Conclusion: Our results suggest that in healthy adolescent females, AMH is not associated with cardiometabolic risk factors.</p>
Lifshitz spacetimes from AdS null and cosmological solutions
We describe solutions of 10-dimensional supergravity comprising null
deformations of with a scalar field, which have
Lifshitz symmetries. The bulk Lifshitz geometry in 3+1-dimensions arises by
dimensional reduction of these solutions. The dual field theory in this case is
a deformation of the N=4 super Yang-Mills theory. We discuss the holographic
2-point function of operators dual to bulk scalars. We further describe
time-dependent (cosmological) solutions which have anisotropic Lifshitz scaling
symmetries. We also discuss deformations of in 11-dimensional
supergravity, which are somewhat similar to the solutions above. In some cases
here, we expect the field theory duals to be deformations of the Chern-Simons
theories on M2-branes stacked at singularities.Comment: Latex, 29pgs, v3. references, minor clarifications (subsection on
Lifshitz geometry seen by scalar probes) added, to appear in JHE
Universal time-dependent deformations of Schrodinger geometry
We investigate universal time-dependent exact deformations of Schrodinger
geometry. We present 1) scale invariant but non-conformal deformation, 2)
non-conformal but scale invariant deformation, and 3) both scale and conformal
invariant deformation. All these solutions are universal in the sense that we
could embed them in any supergravity constructions of the Schrodinger invariant
geometry. We give a field theory interpretation of our time-dependent
solutions. In particular, we argue that any time-dependent chemical potential
can be treated exactly in our gravity dual approach.Comment: 24 pages, v2: references adde
Roles of Molecular Layer Interneurons in Sensory Information Processing in Mouse Cerebellar Cortex Crus II In Vivo
Cerebellar cortical molecular layer interneurons (MLIs) play essential roles in sensory information processing by the cerebellar cortex. However, recent experimental and modeling results are questioning traditional roles for molecular layer inhibition in the cerebellum. receptors uncovered larger EPSCs in PCs whose time to peak, half-width and 10–90% rising time were also significantly slower than in MLIs. Biocytin labeling indicated that the MLIs (but not PCs) are dye-coupled.These findings indicate that tactile face stimulation evokes rapid excitation in MLIs and inhibition occurring at later latencies in PCs in mouse cerebellar cortex Crus II. These results support previous suggestions that the lack of parallel fiber driven PC activity is due to the effect of MLI inhibition
- …