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Author Slepneva, S.; O'Shaughnessy, B.; Vladimirov, A.G.; Rica, S.; Viktorov, E.A.; Huyet, G. doi  openurl
  Title Convective Nozaki-Bekki holes in a long cavity OCT laser Type Journal Article
  Year 2019 Publication Optics Express Abbreviated Journal Opt. Express  
  Volume 27 Issue 11 Pages 16395-16404  
  Keywords  
  Abstract We show, both experimentally and theoretically, that the loss of coherence of a long cavity optical coherence tomography (OCT) laser can be described as a transition from laminar to turbulent flows. We demonstrate that in this strongly dissipative system, the transition happens either via an absolute or a convective instability depending on the laser parameters. In the latter case, the transition occurs via formation of localised structures in the laminar regime, which trigger the formation of growing and drifting puffs of turbulence. Experimentally, we demonstrate that these turbulent bursts arc seeded by appearance of Nozaki-Bekki holes, characterised by the zero field amplitude and pi phase jumps. Our experimental results are supported with numerical simulations based on the delay differential equations model. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement  
  Address [Slepneva, Svetlana; Huyet, Guillaume] Univ Cote Azur, CNRS, INPHINY, Paris, France, Email: svetlana.slepneva@gmail.com  
  Corporate Author Thesis  
  Publisher Optical Soc Amer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1094-4087 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000469227200106 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1031  
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Author Timmermann, T.; Poupin, M.J.; Vega, A.; Urrutia, C.; Ruz, G.A.; Gonzalez, B. doi  openurl
  Title Gene networks underlying the early regulation of Paraburkholderia phytofirmans PsJN induced systemic resistance in Arabidopsis Type Journal Article
  Year 2019 Publication Plos One Abbreviated Journal PLoS One  
  Volume 14 Issue 8 Pages 24 pp  
  Keywords  
  Abstract Plant defense responses to biotic stresses are complex biological processes, all governed by sophisticated molecular regulations. Induced systemic resistance (ISR) is one of these defense mechanisms where beneficial bacteria or fungi prime plants to resist pathogens or pest attacks. In ISR, the defense arsenal in plants remains dormant and it is only triggered by an infection, allowing a better allocation of plant resources. Our group recently described that the well-known beneficial bacterium Paraburkholderia phytofirmans PsJN is able to induce Arabidopsis thaliana resistance to Pseudomonas syringae pv. tomato (Pst) DC3000 through ISR, and that ethylene, jasmonate and salicylic acid are involved in this protection. Nevertheless, the molecular networks governing this beneficial interaction remain unknown. To tackle this issue, we analyzed the temporal changes in the transcriptome of PsJN-inoculated plants before and after being infected with Pst DC3000. These data were used to perform a gene network analysis to identify highly connected transcription factors. Before the pathogen challenge, the strain PsJN regulated 405 genes (corresponding to 1.8% of the analyzed genome). PsJN-inoculated plants presented a faster and stronger transcriptional response at 1-hour post infection (hpi) compared with the non-inoculated plants, which presented the highest transcriptional changes at 24 hpi. A principal component analysis showed that PsJN-induced plant responses to the pathogen could be differentiated from those induced by the pathogen itself. Forty-eight transcription factors were regulated by PsJN at 1 hpi, and a system biology analysis revealed a network with four clusters. Within these clusters LHY, WRKY28, MYB31 and RRTF1 are highly connected transcription factors, which could act as hub regulators in this interaction. Concordantly with our previous results, these clusters are related to jasmonate, ethylene, salicylic, acid and ROS pathways. These results indicate that a rapid and specific response of PsJN-inoculated plants to the virulent DC3000 strain could be the pivotal element in the protection mechanism.  
  Address [Timmermann, Tania; Josefina Poupin, Maria; Urrutia, Cristobal; Ruz, Gonzalo A.; Gonzalez, Bernardo] Univ Adolfo Ibanez, Lab Bioingn, Fac Ingn & Ciencias, Santiago, Chile, Email: bernardo.gonzalez@uai.cl  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000485036900060 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1054  
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Author Ugalde, D.; Parra, P.F.; Lopez-Garcia, D. pdf  doi
openurl 
  Title Assessment of the seismic capacity of tall wall buildings using nonlinear finite element modeling Type Journal Article
  Year 2019 Publication Bulletin Of Earthquake Engineering Abbreviated Journal Bull. Earthq. Eng.  
  Volume 17 Issue 12 Pages 6565-6589  
  Keywords Shear walls; Shear wall buildings; Shear wall models; Seismic response; 2010 Chile earthquake  
  Abstract Two existing RC shear wall buildings of 17 and 26 stories were analyzed using fully nonlinear finite element models, i.e., models that include nonlinear material behavior and geometric nonlinearities. The buildings are located in Santiago, Chile and are representative of Chilean residential buildings in the sense that they have a large number of shear walls. The buildings withstood undamaged the 2010 Chile earthquake even though they were subjected to demands much larger than the code-specified demand. The approach to model the RC shear walls was validated through comparisons with results experimentally obtained from cyclic static tests conducted on isolated wall specimens. Several pushover analyses were performed to assess the global response of the buildings under seismic actions and to evaluate the influence of several modeling issues. Response history analyses were performed considering a ground motion recorded in Santiago during the 2010 Chile earthquake. In general, results (in terms of both global and local response quantities) are consistent with results given by pushover analysis and with the empirically observed lack of damage, a consistency that was not found in a previous study that considered linearly elastic models. The tangential inter-story drift deformation was found to correlate much better with the lack of observable damage than the total inter-story drift deformation typically considered in practice. The analysis also revealed that foundation uplift is possible but does not seem to significantly influence the response. Other modeling issues that were found to deserve further research are the shear stiffness of the walls and the influence of the slabs.  
  Address [Ugalde, David; Lopez-Garcia, Diego] Pontificia Univ Catolica Chile, Dept Struct & Geotech Engn, Santiago, Chile, Email: dlg@ing.puc.cl  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1570-761x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000496337400010 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1073  
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Author Valle, M.A.; Ruz, G.A.; Rica, S. pdf  doi
openurl 
  Title Market basket analysis by solving the inverse Ising problem: Discovering pairwise interaction strengths among products Type Journal Article
  Year 2019 Publication Physica A-Statistical Mechanics And Its Applications Abbreviated Journal Physica A  
  Volume 524 Issue Pages 36-44  
  Keywords Inverse Ising problem; Boltzmann machine; Transactional data base; Pairwise interaction; Minimum spanning tree; Purchase pattern  
  Abstract Large datasets containing the purchasing information of thousands of consumers are difficult to analyze because the possible number of different combinations of products is huge. Thus, market baskets analysis to obtain useful information and find interesting pattern of buying behavior could be a daunting task. Based on the maximum entropy principle, we build a probabilistic model that explains the probability of occurrence of market baskets which is equivalent to Ising models. This type of model allows us to understand and to explore the functional interactions among products that make up the market offer. Additionally, the parameters of the model inferred using Boltzmann learning, allow us to suggest that the buying behavior is very similar to the spin-glass physical system. Moreover, we show that the resulting parameters of the model could be useful to describe the hierarchical structure of the system which leads to interesting information about the different market baskets. (C) 2019 Elsevier B.V. All rights reserved.  
  Address [Valle, Mauricio A.] Univ Finis Terrae, Fac Econ & Negocios, Santiago, Chile, Email: mvalle@uft.cl  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000476966100004 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1022  
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Author Vera-Damian, Y.; Vidal, C.; Gonzalez-Olivares, E. doi  openurl
  Title Dynamics and bifurcations of a modified Leslie-Gower-type model considering a Beddington-DeAngelis functional response Type Journal Article
  Year 2019 Publication Mathematical Methods In The Applied Sciences Abbreviated Journal Math. Meth. Appl. Sci.  
  Volume 42 Issue 9 Pages 3179-3210  
  Keywords Beddington-DeAngelis functional response; Bogdanov-Takens bifurcation; homoclinic bifurcation; Hopf bifurcation; limit cycles; predator-prey model; stability  
  Abstract In this paper, a planar system of ordinary differential equations is considered, which is a modified Leslie-Gower model, considering a Beddington-DeAngelis functional response. It generates a complex dynamics of the predator-prey interactions according to the associated parameters. From the system obtained, we characterize all the equilibria and its local behavior, and the existence of a trapping set is proved. We describe different types of bifurcations (such as Hopf, Bogdanov-Takens, and homoclinic bifurcation), and the existence of limit cycles is shown. Analytic proofs are provided for all results. Ecological implications and a set of numerical simulations supporting the mathematical results are also presented.  
  Address [Vera-Damian, Yrina] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: edvera@alumnos.uai.cl  
  Corporate Author Thesis  
  Publisher Wiley Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0170-4214 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000467275100016 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 998  
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Author Vicuna, L.; Fernandez, M.I.; Vial, C.; Valdebenito, P.; Chaparro, E.; Espinoza, K.; Ziegler, A.; Bustamante, A.; Eyheramendy, S. doi  openurl
  Title Adaptation to Extreme Environments in an Admixed Human Population from the Atacama Desert Type Journal Article
  Year 2019 Publication Genome Biology And Evolution Abbreviated Journal Genome Biol. Evol.  
  Volume 11 Issue 9 Pages 2468-2479  
  Keywords arsenic; positive selection; bladder cancer; Native Americans  
  Abstract Inorganic arsenic (As) is a toxic xenobiotic and carcinogen associated with severe health conditions. The urban population from the Atacama Desert in northern Chile was exposed to extremely high As levels (up to 600 μmg/l) in drinking water between 1958 and 1971, leading to increased incidence of urinary bladder cancer (BC), skin cancer, kidney cancer, and coronary thrombosis decades later. Besides, the Andean Native-American ancestors of the Atacama population were previously exposed for millennia to elevated As levels in water (similar to 120 μg/l) for at least 5,000 years, suggesting adaptation to this selective pressure. Here, we performed two genome-wide selection tests-PBSn1 and an ancestry-enrichment test-in an admixed population from Atacama, to identify adaptation signatures to As exposure acquired before and after admixture with Europeans, respectively. The top second variant selected by PBSn1 was associated with LCE4A-C1orf68, a gene that may be involved in the immune barrier of the epithelium during BC. We performed association tests between the top PBSn1 hits and BC occurrence in our population. The strongest association (P = 0.012) was achieved by the LCE4A-C1orf68 variant. The ancestry-enrichment test detected highly significant signals (P = 1.3 x 10(-9)) mapping MAK16, a gene with important roles in ribosome biogenesis during the G1 phase of the cell cycle. Our results contribute to a better understanding of the genetic factors involved in adaptation to the pathophysiological consequences of As exposure.  
  Address [Vicuna, Lucas; Eyheramendy, Susana] Pontificia Univ Catolica Chile, Fac Math, Dept Stat, Santiago, Chile, Email: mfernandeza@alemana.cl  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1759-6653 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000491234700003 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1091  
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Author Villacres, J.; Arevalo-Ramirez, T.; Fuentes, A.; Reszka, P.; Cheein, F.A. pdf  doi
openurl 
  Title Foliar Moisture Content from the Spectral Signature for Wildfire Risk Assessments in Valparaiso-Chile Type Journal Article
  Year 2019 Publication Sensors Abbreviated Journal Sensors  
  Volume 19 Issue 24 Pages 17 pp  
  Keywords fuel moisture content; wildland urban interface; leaves spectral signature  
  Abstract Fuel moisture content (FMC) proved to be one of the most relevant parameters for controlling fire behavior and risk, particularly at the wildland-urban interface (WUI). Data relating FMC to spectral indexes for different species are an important requirement identified by the wildfire safety community. In Valparaiso, the WUI is mainly composed of Eucalyptus Globulus and Pinus Radiata-commonly found in Mediterranean WUI areas-which represent the 97.51% of the forests plantation inventory. In this work we study the spectral signature of these species under different levels of FMC. In particular, we analyze the behavior of the spectral reflectance per each species at five dehydration stages, obtaining eighteen spectral indexes related to water content and, for Eucalyptus Globulus, the area of each leave-associated with the water content-is also computed. As the main outcome of this research, we provide a validated linear regression model associated with each spectral index and the fuel moisture content and moisture loss, per each species studied.  
  Address [Villacres, Juan; Arevalo-Ramirez, Tito; Cheein, Fernando Auat] Univ Tecn Federico Santa Maria, Dept Elect Engn, Valparaiso 2390123, Chile, Email: juan.villacres@sansano.usm.cl;  
  Corporate Author Thesis  
  Publisher Mdpi Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000517961400138 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1119  
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Author Villena, M.J.; Contreras, M. pdf  doi
openurl 
  Title Global And Local Advertising Strategies: A Dynamic Multi-Market Optimal Control Model Type Journal Article
  Year 2019 Publication Journal Of Industrial And Management Optimization Abbreviated Journal J. Ind. Manag. Optim.  
  Volume 15 Issue 3 Pages 1017-1048  
  Keywords Advertising strategies; multi-market oligopoly; global advertising; differential games  
  Abstract Differential games have been widely used to model advertising strategies of companies. Nevertheless, most of these studies have concentrated on the dynamics and market structure of the problem, neglecting their multi-market dimension. Since nowadays competition typically operates on multi-product contexts and usually in geographically separated markets, the optimal advertising strategies must take into consideration the different levels of disaggregation, especially, for example, in retail multi-product and multi-store competition contexts. In this paper, we look into the decision-making process of a multi-market company that has to decide where, when and how much money to invest in advertising. For this purpose, we develop a model that keeps the dynamic and oligopolistic nature of the traditional advertising game introducing the multi-market dimension of today's economies, while differentiating global (i.e. national TV) from local advertising strategies (i.e. a price discount promotion in a particular store). It is important to note, however, that even though this problem is real for most multi-market companies, it has not been addressed in the differential games literature. On the more technical side, we steer away from the traditional aggregated dynamics of advertising games in two aspects. Firstly, we can model different markets at once, obtaining a global instead of a local optimum, and secondly, since we are incorporating a variable that is common to markets, the resulting equations systems for every market are now coupled. In other words, one's decision in one market does not only affect one's competition in that particular market; it also affects one's decisions and one's competitors in all markets.  
  Address [Villena, Marcelo J.; Contreras, Mauricio] Univ Adolfo Ibanez, Fac Engn & Sci, Av Diagonal Las Torres 2640, Santiago 7941169, Chile, Email: marcelo.villena@uai.cl;  
  Corporate Author Thesis  
  Publisher Amer Inst Mathematical Sciences-Aims Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1547-5816 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000466101700002 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1021  
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Author Vukasovic, T.; Vivanco, J.F.; Celentano, D.; Garcia-Herrera, C. doi  openurl
  Title Characterization of the mechanical response of thermoplastic parts fabricated with 3D printing Type Journal Article
  Year 2019 Publication International Journal Of Advanced Manufacturing Technology Abbreviated Journal Int. J. Adv. Manuf. Technol.  
  Volume 104 Issue 9-12 Pages 4207-4218  
  Keywords Additive manufacturing; Thermoplastic materials; Constitutive modeling  
  Abstract 3D printing has gained great popularity due to its main feature of manufacturing complex geometries. The building process by adding successive layers generates mechanical properties that depend on the printing parameters, where build orientation is one of the most relevant factors. Due to this, the characterization of the mechanical response of these pieces is a challenging task of practical importance to estimate their lifespan. The aim of this study is to characterize the mechanical behavior and define a 3D constitutive model of polymer materials commonly used in 3D printing manufacturing. Hence, ABS and PLA were used with a low-cost desktop printer with which specimens were manufactured in two orthogonal orientations: flat and upright. Tensile and compression tests were performed to this end, where the Young's modulus, yield, and maximum stresses were determined. In the tensile tests, the samples with vertical (upright) orientation showed lower values in the evaluated mechanical properties than the corresponding to the horizontal (flat) orientation. However, no significant difference caused by the printing orientations was observed in the compression tests. Different values of Young's modulus and maximum strength were found between tensile and compression tests for the same material and orientation. Moreover, in order to describe the observed material response, a linear isotropic bimodular model is proposed. This constitutive model, which is fed with the previously obtained tensile and compression data, is used in the simulation of a four-point bending test where it is found to adequately represent the experimentally measured elastic behavior in the load-deflection curve. Thus, the combination of experiments and a bimodular constitutive model contributes to making better predictions of the mechanical response of structures made with 3D printing.  
  Address [Vukasovic, Tomas; Celentano, Diego] Pontificia Univ Catolica Chile, Ctr Invest Nanotecnol & Mat Avanzados CIEN UC, Dept Ingn Mecan & Met, Av Vicuna Mackenna, Santiago 4860, Chile, Email: dcelentano@ing.puc.cl  
  Corporate Author Thesis  
  Publisher Springer London Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0268-3768 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000500220700065 Approved no  
  Call Number UAI @ eduardo.moreno @ Serial 1078  
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