Effects of Education on the Intergenerational Transmission of Labor Income in Mexico

This paper studies the relationship between the labor market earnings of parents and their children, with a particular emphasis on education. We incorporate heterogeneity of levels of income in two ways: first, by examining the transmission mechanism of family income by grouping households according to income levels. Second, we use quantile regressions to evaluate how the earnings distribution changes over time. For this purpose, we use hourly earnings of the household head and decompose it into the estimated hourly earnings and a residual.Education, Labor Income

Fortalezas del carácter, características sociodemográficas y satisfacción con la vida en estudiantes mexicanos

The main purpose of this study was to identify the existing relationship between character strengths and life satisfaction, as well as some sociodemographic aspects related to gender differences. Both the Virtue and Strength Inventory (IVYF; Cosentino & Castro, 2008) and the Satisfaction with Life Scale (SWLS; Diener, Emmons, Larsen & Griffin, 1985) were administered to 343 undergraduate students whose primary major of study pertained to health professions. Results indicated that for women, love and gratitude are the strengths that explained 21.3 % of the variance regarding satisfaction with life, while love and social intelligence predicted 44.5 % of life satisfaction for men. Results are discussed under the light of cultural differences

Yard-Sale exchange on networks: Wealth sharing and wealth appropriation

Yard-Sale (YS) is a stochastic multiplicative wealth-exchange model with two phases: a stable one where wealth is shared, and an unstable one where wealth condenses onto one agent. YS is here studied numerically on 1d rings, 2d square lattices, and random graphs with variable average coordination, comparing its properties with those in mean field (MF). Equilibrium properties in the stable phase are almost unaffected by the introduction of a network. Measurement of decorrelation times in the stable phase allow us to determine the critical interface with very good precision, and it turns out to be the same, for all networks analyzed, as the one that can be analytically derived in MF. In the unstable phase, on the other hand, dynamical as well as asymptotic properties are strongly network-dependent. Wealth no longer condenses on a single agent, as in MF, but onto an extensive set of agents, the properties of which depend on the network. Connections with previous studies of coalescence of immobile reactants are discussed, and their analytic predictions are successfully compared with our numerical results.Comment: 10 pages, 7 figures. Submitted to JSTA

ALGSICS - Combining physics and cryptography to enhance security and privacy in RFID systems

In this paper, we introduce several new mechanisms that are cheap to implement or integrate into RFID tags and that at the same time enhance their security and privacy properties. Our aim is to provide solutions that make use of existing (or expected) functionality on the tag or that are inherently cheap and thus, enhance the privacy friendliness of the technology "almost" for free. Our proposals, for example, make use of environmental information (presence of light temperature, humidity, etc.) to disable or enable the RFID tag. A second possibility that we explore is the use of delays in revealing a secret key used to later establish a secure communication channel. We also introduce the idea of a "sticky tag," which can be used to re-enable a disabled (or killed) tag whenever the user considers it to be safe. We discuss the security and describe usage scenarios for all solutions. Finally, we review previous works that use physical principles to provide security and privacy in RFID systems

The impact of histopathology and NAB2-STAT6 fusion subtype in classification and grading of meningeal solitary fibrous tumor/hemangiopericytoma.

Meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) is a rare tumor with propensity for recurrence and metastasis. Although multiple classification schemes have been proposed, optimal risk stratification remains unclear, and the prognostic impact of fusion status is uncertain. We compared the 2016 WHO CNS tumor grading scheme (CNS-G), a three-tier system based on histopathologic phenotype and mitotic count, to the 2013 WHO soft-tissue counterpart (ST-G), a two-tier system based on mitotic count alone, in a cohort of 133 patients [59 female, 74 male; mean age 54 years (range 20-87)] with meningeal SFT/HPC. Tumors were pathologically confirmed through review of the first tumor resection (n = 97), local recurrence (n = 35), or distant metastasis (n = 1). A STAT6 immunostain showed nuclear expression in 132 cases. NAB2-STAT6 fusion was detected in 99 of 111 successfully tested tumors (89%) including the single STAT6 immunonegative tumor. Tumors were classified by CNS-G as grade 1 (n = 43), 2 (n = 41), or 3 (n = 49), and by ST-G as SFT (n = 84) or malignant SFT (n = 49). Necrosis was present in 16 cases (12%). On follow-up, 42 patients had at least one subsequent recurrence or metastasis (7 metastasis only, 33 recurrence only, 2 patients had both). Twenty-nine patients died. On univariate analysis, necrosis (p = 0.002), CNS-G (p = 0.01), and ST-G (p = 0.004) were associated with recurrence-free (RFS) but not overall survival (OS). NAB2-STAT6 fusion type was not significantly associated with RFS or OS, but was associated with phenotype. A modified ST-G incorporating necrosis showed higher correlation with RFS (p = 0.0006) and remained significant (p = 0.02) when considering only the primary tumors. From our data, mitotic rate and necrosis appear to stratify this family of tumors most accurately and could be incorporated in a future grading scheme

Spatio-temporal variation in the composition of the macroalgae assemblage of the intertidal rocky zone from maitencillo, valparaíso, central coast of Chile

Indexación: Scopus.Records on the diversity of algae serve as a foundation for establishing management and environmental protection programs, as well as for determining new commercial uses of algae. With this context in mind, the goal of the present study was to determine the richness, coverage, and composition of the macroalgae assemblage in the intertidal zone of Maitencillo, Valparaíso, Chile over the course of 3 years (2013-2015). A total of 29 species were recorded from 3 phyla - 23 Rhodophyta; 3 Ochrophyta, of the Phaeophyceae class; and 3 Chlorophyta. Species richness presented high spatial and temporal variations, with these variations most significantly explained by intertidal zone (61%) and the seasons (31%). The highest levels of specific richness were recorded in the mid and lower intertidal zones (14 species) in spring, as well as in the lower intertidal zone (14 species) during summer. The lowest values of specific richness were recorded for the mid intertidal zone (2 species) during fall. The distinct levels of the intertidal zone also notably impacted algae assemblage, explaining 53% of variation while the seasons explained 18% of variation. The greatest coverage was recorded in the mid intertidal zone during spring, with a predominance of Mazzaella laminarioides and Ulva spp. complex. In turn, the lowest coverage was found in fall, linked with processes of sand accretion. In rocky walls, the Pyropia complex dominated. Results indicate a marked pattern of vertical and seasonal distribution in the macroalgae assemblage, as well as notably high presence of Rhodophyta species. This benthic flora description serves to update information on the diversity of representative algal species from Valparaíso Region of Chile. © 2018, Universidad de Valparaiso. All rights reserved

FPGA Time-Bounded Unclonable Authentication

Abstract. This paper introduces a novel technique for extracting the unique tim-ing signatures of the FPGA configurable logic blocks in a digital form over the space of possible challenges. A new class of physical unclonable functions that enables inputs challenges such as timing, digital, and placement challenges can be built upon the delay signatures. We introduce a suite of new authentication protocols that take into account non-triviality of bitstream reverse-engineering in addition to the FPGA’s unprecedented speed in responding to challenges. Our technique is secure against various attacks and robust to fluctuations in opera-tional conditions. Proof of concept implementation of the signature extraction and evaluations of the proposed methods are demonstrated on Xilinx Virtex 5 FPGAs. Experimental results demonstrate practicality of the proposed techniques.

Differences in pollination syndromes and the frequency of autonomous delayed selfing between co-flowering hibiscus aponeurus (sprague and hutch) and h. Flavifolius (ulbr) from Kenya.

Delayed autonomous selfing offers a mechanism for seed production when pollination levels are low or unpredictable. At Mpala Research Centre (MRC) in Kenya, we examined the relationships between floral attraction, insect visitation, and delayed autonomous selfing through backwards stylar curvature in the co-flowering Hibiscus aponeurus and H. flavifolius. Despite producing similar pollen and nectar rewards, visitation rates and the composition of floral visitor guilds varied significantly between these species. Across four years of observations, floral visitation in H. flavifolius was dominated by bees, and in H. aponeurus by a mixture of bees, butterflies and beetles. Visitation rates to H. flavifolius flowers (range 0.17 - 2.1 visits flr-1hr-1) were two times greater than to H. aponeurus flowers (range 0 - 2.7 visits flr-1hr-1), which resulted in significantly higher pollen deposition and removal rates in H. flavifolius than in H. aponeurus. Field crosses demonstrated little pollen limitation in either species. In open-pollinated flowers, H. aponeurus displayed significantly greater stylar curvature and apparent self-pollination than did H. flavifolius. Floral attributes in H. aponeurus, such as a smaller corolla size and a downwards orientation of the stylar column, also suggest that delayed selfing is a more important mechanism of reproductive assurance in this species than in H. flavifolius. Determining whether these differences in insect visitation and stylar curvature are characteristic for these species or are unique to MRC will require comparison with populations located in other parts of the ranges, genetic tests of selfing rates, and chemical analyses of nectar, pollen, and floral volatiles