Modelos y sistemas dinámicos

En este texto se recogen las materias que, durante cinco años, han sido impartidas por los autores en la asignatura "Modelos y Sistemas Dinámicos" de la licenciatura de Ciencias del Mar de Ila Universidad de Cádi

Probability of deafault using the logit model: The impact of explanatory variable and data base selection

2nd INTERNATIONAL SCIENTIFIC CONFERENCE WHITHER OUR ECONOMIES – 2012 Conference ProceedingsThe Spanish economy is suffering a severe financial crisis which is affecting all Spanish savings banks as well as some major banks. One of the triggers of the crisis is the high companies’ default rate experienced in the last years due to a deficient credit risk management by financial institutions. Credit risk analysis is mainly undertaken using the logit model to calculate the probability of default of the companies. In this work we describe some problems that arise when using this model and that can have a negative impact on the quality of the results obtained.Bartual Sanfeliu, C.; García García, F.; Guijarro, F.; Romero Civera, A. (2012). Probability of deafault using the logit model: The impact of explanatory variable and data base selection. International Scientific Conference: Whither our Economics. 118-124. http://hdl.handle.net/10251/61415S11812

Transcriptomic and Metabolomic Response to High Light in the Charophyte Alga Klebsormidium nitens

The characterization of the molecular mechanisms, such as high light irradiance resistance, that allowed plant terrestralization is a cornerstone in evolutionary studies since the conquest of land by plants played a pivotal role in life evolution on Earth. Viridiplantae or the green lineage is divided into two clades, Chlorophyta and Streptophyta, that in turn splits into Embryophyta or land plants and Charophyta. Charophyta are used in evolutionary studies on plant terrestralization since they are generally accepted as the extant algal species most closely related to current land plants. In this study, we have chosen the facultative terrestrial early charophyte alga Klebsormidium nitens to perform an integrative transcriptomic and metabolomic analysis under high light in order to unveil key mechanisms involved in the early steps of plants terrestralization. We found a fast chloroplast retrograde signaling possibly mediated by reactive oxygen species and the inositol polyphosphate 1-phosphatase (SAL1) and 3′-phosphoadenosine-5′-phosphate (PAP) pathways inducing gene expression and accumulation of specific metabolites. Systems used by both Chlorophyta and Embryophyta were activated such as the xanthophyll cycle with an accumulation of zeaxanthin and protein folding and repair mechanisms constituted by NADPH-dependent thioredoxin reductases, thioredoxin-disulfide reductases, and peroxiredoxins. Similarly, cyclic electron flow, specifically the pathway dependent on proton gradient regulation 5, was strongly activated under high light. We detected a simultaneous co-activation of the non-photochemical quenching mechanisms based on LHC-like stress related (LHCSR) protein and the photosystem II subunit S that are specific to Chlorophyta and Embryophyta, respectively. Exclusive Embryophyta systems for the synthesis, sensing, and response to the phytohormone auxin were also activated under high light in K. nitens leading to an increase in auxin content with the concomitant accumulation of amino acids such as tryptophan, histidine, and phenylalanine.España Ministerio de Ciencia e Innovación MINOTAUR (BIO2017-84066-R

Optional models for strengthening the Spanish co-operative banking sector

Authors contributing to Business Systems & Economics agree to publish their articles, allowing third parties to share their work (copy, distribute, transmit) and to adapt it, under the condition that the authors are given credit. Authors retain copyright of their work, with publication rights granted to Mykolas Romeris UniversityThe financial crisis that started in 2008 has had a major impact on the Spanish financial system, including the co-operative banking sector. Among the restructuring measures being considered for the industry, one option is to create larger co-operative banking groups, employing different formulas. Given this context, it is interesting to compare the success achieved by the main European cooperative banking groups, which must surely serve as rolemodels for the Spanish process. The present study makes this comparison both from the usual economic and financial perspective and by taking the traditional cooperative style of management into account. The methodology used is the Analytic Hierarchy Process (AHP), enabling the use of both quantitative and qualitative information, as well as the opinions of experts.Aznar Bellver, J.; Bartual Sanfeliu, C.; García García, F.; Romero Civera, A. (2012). Optional models for strengthening the Spanish co-operative banking sector. Business Systems & Economics. 2(2):1-18. http://hdl.handle.net/10251/60120S1182

Credit Risk Analysis: Reflections on the Use of the Logit Model

Creative Commons Attribution License (CCAL). Attribution 2.5 Generic (CC BY 2.5)The present economic and financial crisis has underlined the importance to financial institutions and investors of having access to efficient methods of quantifying credit risk, or the probability of default. The logit models are among the techniques commonly used by large organizations and rating agencies for predicting insolvency. However, it should be borne in mind that some problems arise when using these models, such as the selection of the explanatory variables or the composition of the sample from which the model is obtained. These aspects have a decisive influence on the prediction models used to quantify companies’ credit risk. The present study describes the problems that arise with logit on a sample of Spanish companies and shows that the estimated prediction models are indeed modified by changes in the sample on which they are based.Bartual Sanfeliu, C.; García García, F.; Giménez Molina, V.; Romero Civera, A. (2012). Credit Risk Analysis: Reflections on the Use of the Logit Model. Journal of Applied Finance & Banking. 2(6):1-13. http://hdl.handle.net/10251/60119S1132

Becoming primary caregivers? Unemployed fathers caring alone in Spain

This article analyses how unemployed fathers with employed partners broach childcare and how they conceive of their own identities. It aims primarily to determine whether these fathers actually play the part of primary caregivers. The analysis is based on in-depth interviews with 26 unemployed fathers who spent at least three months caring for their children. The findings show that these fathers engaged intensively in a wide variety of caring tasks. Nonetheless, their role as primary caregivers is called into question on the grounds of attitude. They tended to take for granted that they should set aside time and space for themselves, adding to their partners’ dual workload. Moreover, the overall responsibility for care fell largely on mothers. Subjectively speaking, while one group of fathers resorted to egalitarian precepts to normalise their situation, for many others, the inability to meet the standard expectations of traditional masculinity prompted an identity conflict.2019-2

New cinnamic – N-benzylpiperidine and cinnamic – N,N-dibenzyl(N-methyl)amine hybrids as Alzheimer-directed multitarget drugs with antioxidant, cholinergic, neuroprotective and neurogenic properties

Here we describe new families of multi-target directed ligands obtained by linking antioxidant cinnamic-related structures with N-benzylpiperidine (NBP) or N,N-dibenzyl(N-methyl)amine (DBMA) fragments. Resulting hybrids, in addition to their antioxidant and neuroprotective properties against mitochondrial oxidative stress, are active at relevant molecular targets in Alzheimer’s disease, such as cholinesterases (hAChE and hBuChE) and monoamine oxidases (hMAO-A and hMAO-B). Hybrids derived from umbellic – NBP (8), caffeic – NBP (9), and ferulic – DBMA (12) displayed balanced biological profiles, with IC50s in the low-micromolar and submicromolar range for hChEs and hMAOs, and an antioxidant potency comparable to vitamin E. Moreover, the caffeic – NBP hybrid 9 is able to improve the differentiation of adult SGZ-derived neural stem cells into a neuronal phenotype in vitro.Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO, grants SAF2012-31035 and SAF2015-64948-C2-1-R to MIRF; grant SAF2014-52940-R to APC) partially financed by FEDER funds, and Consejo Superior de Investigaciones Científicas (CSIC, grant PIE-201580E109) is gratefully acknowledged. ME thanks COLCIENCIAS (Colombia) for a Ph.D. fellowship.Peer reviewe