Migration patterns under different scenarios of sea level rise

We propose a framework to examine future migration patterns of people under different sea level rise scenarios using models of human migration. Specifically, we couple a sea level rise model with a data-driven model of human migration, creating a generalized joint model of climate driven migration that can be used to simulate population distributions under potential future sea level rise scenarios. We show how this joint model relaxes assumptions in existing efforts to model climate driven human migration, and use it to simulate how migration, driven by sea level rise, differs from baseline migration patterns. Our results show that the effects of sea level rise are pervasive, expanding beyond coastal areas via increased migration, and disproportionately affecting some areas of the United States. The code for reproducing this study is available at https://github.com/calebrob6/migration-slr.Comment: In submission to PLOS On

Actualización de la cartilla “modelos de puentes de placa y viga y alcantarillas de cajón” de 1988 para superestructuras en concreto reforzado con luces entre 10 y 20 metros

Trabajo de investigaciónEste trabajo contempla la actualización de los diseños de puentes de placa y viga en concreto reforzado de la cartilla “modelos de puentes de placa y viga y alcantarillas de cajón” de 1988 bajo los parámetros de diseño de la norma colombiana de puentes (cpp-14) para superestructuras en concreto reforzado con luces entre 10 y 20 metros.INTRODUCCIÓN 1. GENERALIDADES 2. ANÁLISIS DE RESULTADOS 3. CONCLUSIONES 4. RECOMENDACIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Civi

Dynamical Bonding Driving Mixed Valency in a Metal Boride

Samarium hexaboride is an anomaly, having many exotic and seemingly mutually incompatible properties. It was proposed to be a mixed-valent semiconductor, and later - a topological Kondo insulator, and yet has a Fermi surface despite being an insulator. We propose a new and unified understanding of SmB$_6$ centered on the hitherto unrecognized dynamical bonding effect: the coexistence of two Sm-B bonding modes within SmB$_6$, corresponding to different oxidation states of the Sm. The mixed valency arises in SmB$_6$ from thermal population of these distinct minima enabled by motion of B. Our model simultaneously explains the thermal valence fluctuations, appearance of magnetic Fermi surface, excess entropy at low temperatures, pressure-induced phase transitions, and related features in Raman spectra and their unexpected dependence on temperature and boron isotope

Hierarchically cocompact classifying spaces for mapping class groups of surfaces

We define the notion of a hierarchically cocompact classifying space for a family of subgroups of a group. Our main application is to show that the mapping class group Mod ( S ) of any connected oriented compact surface S , possibly with punctures and boundary components and with negative Euler characteristic has a hierarchically cocompact model for the family of virtually cyclic subgroups of dimension at most vcd Mod ( S ) + 1 . When the surface is closed, we prove that this bound is optimal. In particular, this answers a question of Lück for mapping class groups of surfaces

Emergeables: Deformable Displays for Continuous Eyes-Free Mobile Interaction

International audienceWe present the concept of Emergeables - mobile surfaces that can deform or 'morph' to provide fully-actuated, tangible controls. Our goal in this work is to provide the flexibility of graphical touchscreens, coupled with the affordance and tactile benefits offered by physical widgets. In contrast to previous research in the area of deformable displays, our work focuses on continuous controls (e.g., dials or sliders), and strives for fully-dynamic positioning, providing versatile widgets that can change shape and location depending on the user's needs. We describe the design and implementation of two prototype emergeables built to demonstrate the concept, and present an in-depth evaluation that compares both with a touchscreen alternative. The results show the strong potential of emergeables for on-demand, eyes-free control of continuous parameters, particularly when comparing the accuracy and usability of a high-resolution emergeable to a standard GUI approach. We conclude with a discussion of the level of resolution that is necessary for future emergeables, and suggest how high-resolution versions might be achieved

Effects of alternative bedding substrates on lamb welfare, productive performance, and meat quality during the finishing phase of fattening

The study analyzed the effect of using sawdust, cellulose, straw, and rice husk bedding on the welfare, performance and meat quality of lambs during the finishing phase of fattening. Ninety-six lambs (fed ad libitum with concentrate) were assigned to pens containing 1 of 4 bedding materials in groups of 12 for 14 days. Live weight and feed consumption were recorded to estimate daily gain and conversion index, and carcass and meat quality variables were measured. Stereotypies, exploratory interactions with bedding material, and agonistic and affiliative interactions between animals were recorded by continuous sampling techniques using video recording. The substrates affected behavior and stress response variables. There were more stereotypies and agonistic interactions at the beginning of the experiment in all treatments (P ≤ 0.05). The lambs fattened on cellulose bedding interacted more with the substrate throughout the finishing stage (P ≤ 0.05), where there were also more affiliative interactions (P ≤ 0.05). Stress levels were lower in lambs on straw, followed by cellulose. No significant differences in production or carcass and meat quality traits were observed between treatments. The results suggest that all substrates evaluated could be efficiently incorporated into the system as bedding material without affecting productivity or product quality

Rainich theory for type D aligned Einstein-Maxwell solutions

The original Rainich theory for the non-null Einstein-Maxwell solutions consists of a set of algebraic conditions and the Rainich (differential) equation. We show here that the subclass of type D aligned solutions can be characterized just by algebraic restrictions.Comment: 12 pages; v2: appendix with notatio

First Light LBT AO Images of HR 8799 bcde at 1.65 and 3.3 Microns: New Discrepancies between Young Planets and Old Brown Dwarfs

As the only directly imaged multiple planet system, HR 8799 provides a unique opportunity to study the physical properties of several planets in parallel. In this paper, we image all four of the HR 8799 planets at H-band and 3.3 microns with the new LBT adaptive optics system, PISCES, and LBTI/LMIRCam. Our images offer an unprecedented view of the system, allowing us to obtain H and 3.3$ micron photometry of the innermost planet (for the first time) and put strong upper-limits on the presence of a hypothetical fifth companion. We find that all four planets are unexpectedly bright at 3.3 microns compared to the equilibrium chemistry models used for field brown dwarfs, which predict that planets should be faint at 3.3 microns due to CH4 opacity. We attempt to model the planets with thick-cloudy, non-equilibrium chemistry atmospheres, but find that removing CH4 to fit the 3.3 micron photometry increases the predicted L' (3.8 microns) flux enough that it is inconsistent with observations. In an effort to fit the SED of the HR 8799 planets, we construct mixtures of cloudy atmospheres, which are intended to represent planets covered by clouds of varying opacity. In this scenario, regions with low opacity look hot and bright, while regions with high opacity look faint, similar to the patchy cloud structures on Jupiter and L/T transition brown-dwarfs. Our mixed cloud models reproduce all of the available data, but self-consistent models are still necessary to demonstrate their viability.Comment: Accepted to Ap

From error bounds to the complexity of first-order descent methods for convex functions

This paper shows that error bounds can be used as effective tools for deriving complexity results for first-order descent methods in convex minimization. In a first stage, this objective led us to revisit the interplay between error bounds and the Kurdyka-\L ojasiewicz (KL) inequality. One can show the equivalence between the two concepts for convex functions having a moderately flat profile near the set of minimizers (as those of functions with H\"olderian growth). A counterexample shows that the equivalence is no longer true for extremely flat functions. This fact reveals the relevance of an approach based on KL inequality. In a second stage, we show how KL inequalities can in turn be employed to compute new complexity bounds for a wealth of descent methods for convex problems. Our approach is completely original and makes use of a one-dimensional worst-case proximal sequence in the spirit of the famous majorant method of Kantorovich. Our result applies to a very simple abstract scheme that covers a wide class of descent methods. As a byproduct of our study, we also provide new results for the globalization of KL inequalities in the convex framework. Our main results inaugurate a simple methodology: derive an error bound, compute the desingularizing function whenever possible, identify essential constants in the descent method and finally compute the complexity using the one-dimensional worst case proximal sequence. Our method is illustrated through projection methods for feasibility problems, and through the famous iterative shrinkage thresholding algorithm (ISTA), for which we show that the complexity bound is of the form $O(q^{k})$ where the constituents of the bound only depend on error bound constants obtained for an arbitrary least squares objective with $\ell^1$ regularization