Motioning connected subgraphs into a graph

In this paper we study connected subgraphs and how to motion them inside a connected graph preserving the connectivity. We determine completely the group of movements.Comment: 17 pages, 18 figure

Investing cash transfers to raise long term living standards

The authors test whether poor households use cash transfers to invest in income generating activities that they otherwise would not have been able to do. Using data from a controlled randomized experiment, they find that transfers from the Oportunidades program to households in rural Mexico resulted in increased investment in micro-enterprise and agricultural activities. For each peso transferred, beneficiary households used 88 cents to purchase consumption goods and services, and invested the rest. The investments improved the household's ability to generate income with an estimated rate of return of 17.55 percent, suggesting that these households were both liquidity and credit constrained. By investing transfers to raise income, beneficiary households were able to increase their consumption by 34 percent after five and a half years in the program. The results suggest that cash transfers to the poor may raise long-term living standards, which are maintained after program benefits end.Economic Theory&Research,Small Area Estimation Poverty Mapping,Municipal Housing and Land,Land and Real Estate Development,Real Estate Development

Convergence and Trade-Offs in Riemannian Gradient Descent and Riemannian Proximal Point

In this work, we analyze two of the most fundamental algorithms in geodesically convex optimization: Riemannian gradient descent and (possibly inexact) Riemannian proximal point. We quantify their rates of convergence and produce different variants with several trade-offs. Crucially, we show the iterates naturally stay in a ball around an optimizer, of radius depending on the initial distance and, in some cases, on the curvature. In contrast, except for limited cases, previous works bounded the maximum distance between iterates and an optimizer only by assumption, leading to incomplete analyses and unquantified rates. We also provide an implementable inexact proximal point algorithm yielding new results on minmax problems, and we prove several new useful properties of Riemannian proximal methods: they work when positive curvature is present, the proximal operator does not move points away from any optimizer, and we quantify the smoothness of its induced Moreau envelope. Further, we explore beyond our theory with empirical tests

Derechos y Humanos sobre la exclusión a través del derecho

En el presente texto el autor desarrolla la idea que el Derecho en la modernidad se caracteriza por intentar abarcar toda la existencia del ser humano, normando desde su nacimiento hasta su muerte (I). En este contexto el concepto de persona es clave y ha sido determinante para poder acceder a los beneficios de las comunidades, organizadas en Estados, a través de derechos (II). Ante ello, en las últimas décadas se ha suscitado una serie de discusiones sobre la inclusión o exclusión de individuos y grupos, ya sea ampliando o reduciendo el acceso a derechos (III). En esto se han desarrollado ciertas herramientas jurídicas destinadas a la exclusión, como lo son la condicionalidad de los derechos, la denegación organizada de justicia y la creación de subestatutos e identidades (IV).  DOI: http://dx.doi.org/10.22518/16578953.70

Accelerated Methods for Riemannian Min-Max Optimization Ensuring Bounded Geometric Penalties

In this work, we study optimization problems of the form $\min_x \max_y f(x, y)$, where $f(x, y)$ is defined on a product Riemannian manifold $\mathcal{M} \times \mathcal{N}$ and is $\mu_x$-strongly geodesically convex (g-convex) in $x$ and $\mu_y$-strongly g-concave in $y$, for $\mu_x, \mu_y \geq 0$. We design accelerated methods when $f$ is $(L_x, L_y, L_{xy})$-smooth and $\mathcal{M}$, $\mathcal{N}$ are Hadamard. To that aim we introduce new g-convex optimization results, of independent interest: we show global linear convergence for metric-projected Riemannian gradient descent and improve existing accelerated methods by reducing geometric constants. Additionally, we complete the analysis of two previous works applying to the Riemannian min-max case by removing an assumption about iterates staying in a pre-specified compact set.Comment: added weakly-convex analysis, and some remark

Self-propelled Vicsek particles at low speed and low density

We study through numerical simulation the Vicsek model for very low speeds and densities. We consider scalar noise in two and three dimensions and vector noise in three dimensions. We focus on the behavior of the critical noise with density and speed, trying to clarify seemingly contradictory earlier results. We find that, for scalar noise, the critical noise is a power law in both density and speed, but although we confirm the density exponent in two dimensions, we find a speed exponent different from earlier reports (we consider lower speeds than previous studies). On the other hand, for the vector noise case we find that the dependence of the critical noise cannot be separated as a product of power laws in speed and density. Finally, we study the dependence of the relaxation time with speed. At the critical point we find a power law, with the same exponent in two and three dimensions.Fil: Rubio Puzzo, Maria Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; ArgentinaFil: De Virgiliis, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería; ArgentinaFil: Grigera, Tomas Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; Argentin

Strong Convexity of Sets in Riemannian Manifolds

Convex curvature properties are important in designing and analyzing convex optimization algorithms in the Hilbertian or Riemannian settings. In the case of the Hilbertian setting, strongly convex sets are well studied. Herein, we propose various definitions of strong convexity for uniquely geodesic sets in a Riemannian manifold. We study their relationship, propose tools to determine the geodesic strongly convex nature of sets, and analyze the convergence of optimization algorithms over those sets. In particular, we demonstrate that the Riemannian Frank-Wolfe algorithm enjoys a global linear convergence rate when the Riemannian scaling inequalities hold

Influence of Development and Dietary Phospholipid Content and Composition on Intestinal Transcriptome of Atlantic Salmon (Salmo salar)

The inclusion of intact phospholipids in the diet is essential during larval development and can improve culture performance of many fish species. The effects of supplementation of dietary phospholipid from marine (krill) or plant (soy lecithin) sources were investigated in Atlantic salmon,Salmo salar. First feeding fry were fed diets containing either krill oil or soybean lecithin supplying phospholipid at 2.6%, 3.2%, 3.6% and 4.2% of diet. Fish were sampled at ~ 2.5 g (~1,990°day post fertilization, dpf) and ~10 g (2,850°dpf). By comparison of the intestinal transcriptome in specifically chosen contrasts, it was determined that by 2,850°dpf fish possessed a profile that resembled that of mature and differentiated intestinal cell types with a number of changes specific to glycerophospholipid metabolism. It was previously shown that intact phospholipids and particularly phosphatidylcholine are essential during larval development and that this requirement is associated with the inability of enterocytes in young fry to endogenously synthesize sufficient phospholipid for the efficient export of dietary lipid. In the immature phase (~1,990°dpf), the dietary phospholipid content as well as its class composition impacted on several biochemical and morphological parameters including growth, but these differences were not associated with differences in intestinal transcriptomes. The results of this study have made an important contribution to our understanding of the mechanisms associated with lipid transport and phospholipid biosynthesis in early life stages of fish

Innovación Tecnológica en Empresas Chilenas: Un Estudio Empírico Basado en Patentes

Technological Innovation in Chilean Firms: An Empirical Study Based on PatentsLiterature has focused on studying patents in particular industries, subsectors or firms, mainly in developed countries. The level or quantity of patents in Chile during the period 2007-2012 on average reached 12 triadic families, while in countries like Argentina and Mexico presented averages of 12 and 15 respectively. The overall average for the same period amounted to 48,242 OECD triadic patent families. This shows the interest of the scientific community to study the phenomenon of patent creation, and, on the other hand, the large technological gap between developed and developing countries. We propose to study the determinants of patenting in Chilean firms, as a case of a developing country. We use a probit model where the dependent variable takes value one if the firm has or is in the process of obtaining an invention patent (technological) and zero if not. Our database has 4,338 Chilean firms, is cross-sectional and corresponds to an extract of the Eighth Survey of Innovation in Firms 2011-2012. The results show that the age of the firm, the base of existing knowledge, and the use of governmental instruments to support R&D have a positive effect on creation of patents