A cut finite element method for coupled bulk-surface problems on time-dependent domains

In this contribution we present a new computational method for coupled bulk-surface problems on time-dependent domains. The method is based on a space-time formulation using discontinuous piecewise linear elements in time and continuous piecewise linear elements in space on a fixed background mesh. The domain is represented using a piecewise linear level set function on the background mesh and a cut finite element method is used to discretize the bulk and surface problems. In the cut finite element method the bilinear forms associated with the weak formulation of the problem are directly evaluated on the bulk domain and the surface defined by the level set, essentially using the restrictions of the piecewise linear functions to the computational domain. In addition a stabilization term is added to stabilize convection as well as the resulting algebraic system that is solved in each time step. We show in numerical examples that the resulting method is accurate and stable and results in well conditioned algebraic systems independent of the position of the interface relative to the background mesh

Inflation Dynamics’ Micro Foundations: How Important is Imperfect Competition Really?

This paper analyzes price formation and dynamics according to the industry structure. It divides manufacturing industries of Mexico into two groups: perfectly and imperfectly competitive. The results show that imperfectly competitive industries predominate. Then this classification is used to build consumer price sub indexes for the goods of both sectors. These sub indexes’ inflation dynamics indicate that the exchange rate pass-through in the perfectly competitive sector is significantly higher than in the imperfectly competitive sector, while wage pass-through only affects the imperfectly competitive sector. Also, that inflation inertia is lower in the former than in the latter; adding up in more volatility of the perfectly competitive inflation rate. For policy makers an interesting feature of the perfectly competitive price index is that the evidence suggests that its variations precede those of the imperfectly competitive price index. For economic theorists these features validate recent macroeconomic models with heterogeneous price setting behaviorPanzar-Rosse, Industry Structure, Inflation, Price Dynamics, Price Indexes

The Ambient Horn: Designing a novel audio-based learning experience

The Ambient Horn is a novel handheld device designed to support children learning about habitat distributions and interdependencies in an outdoor woodland environment. The horn was designed to emit non-speech audio sounds representing ecological processes. Both symbolic and arbitrary mappings were used to represent the processes. The sounds are triggered in response to the children’s location in certain parts of the woodland. A main objective was to provoke children into interpreting and reflecting upon the significance of the sounds in the context in which they occur. Our study of the horn being used showed the sounds to be provocative, generating much discussion about what they signified in relation to what the children saw in the woodland. In addition, the children appropriated the horn in creative ways, trying to ‘scoop’ up new sounds as they walked in different parts of the woodland

The observation of photon echoes from evanescently coupled rare-earth ions in a planar waveguide

We report the measurement of the inhomogeneous linewidth, homogeneous linewidth and spin state lifetime of Pr3+ ions in a novel waveguide architecture. The TeO2 slab waveguide deposited on a bulk Pr3+:Y2SiO5 crystal allows the 3H4 - 1D2 transition of Pr3+ ions to be probed by the optical evanescent field that extends into the substrate. The 2 GHz inhomogeneous linewidth, the optical coherence time of 70 +- 5 us, and the spin state lifetime of 9.8 +- 0.3 s indicate that the properties of ions interacting with the waveguide mode are consistent with those of bulk ions. This result establishes the foundation for large, integrated and high performance rare-earth-ion quantum systems based on a waveguide platform.Comment: 5 pages, 5 figure

ILR Impact Brief - Community College Websites and Barriers to Access

[Excerpt] Community colleges, on average, serve 335 students with disabilities, although that number climbs to 5,000 at the largest college surveyed for this project. Nearly all community colleges that participated in the survey rely on the web for a variety of student services, but only half have instituted requirements regarding web accessibility for individuals with disabilities. Actual evaluations of accessibility and ease of use revealed that none of the websites analyzed complied with all federal standards on accessibility, and many web pages encompassed usability obstacles (e.g., unfamiliar terminology, unintuitive navigation schemes, and hard-to-read design elements) that affected disabled and non-disabled individuals alike

Patient-centered endodontic outcomes: a narrative review.

IntroductionRoot canal treatment (RCT) success criteria inform us of the path to bony healing and of prognostic factors, but tell little about how the patient perceives, feels, or values RCT. Patients choose, undergo, and pay for RCT, they live with the result, and inform their community. The purpose of this narrative review was to appraise patient-centered outcomes of initial non-surgical RCT and nonsurgical retreatment, in adults.Materials and methodsPatient-centered RCT outcome themes were identified in the extant literature: quality of life, satisfaction, anxiety, fear, pain, tooth survival and cost. Narrative review was applied because the disparate themes and data were unsuited to systematic review or meta-analysis.ResultsApplication of the Oral Health Impact Profile (OHIP) demonstrated that disease of pulpal origin affects quality of life with moderate severity, primarily through physical pain and psychological discomfort, and that RCT results in broad improvement of quality of life. Satisfaction with RCT is extremely high, but cost is the primary reason for dissatisfaction. Anxiety and fear affect RCT patients, profoundly influencing their behaviors, including treatment avoidance, and their pain experience. Fear of pain is "fair" to "very much" prior to RCT. Pain is widely feared, disliked, and remembered; however, disease of pulpal origin generally produces moderate, but not severe pain. RCT causes a dramatic decrease in pain prevalence and severity over the week following treatment. Survival rates of teeth after RCT are very high; complication rates are low. Cost is a barrier to RCT, but initial costs, lifetime costs, cost effectiveness, cost utility, and cost benefit all compare extremely well to the alternatives involving replacement using implants or fixed prostheses.ConclusionDentists must strive to reduce anxiety, fear, experienced and remembered pain, and to accurately inform and educate their patients with respect to technical, practical and psychosocial aspects of RCT