Extracellular matrix components are required to protect bacillus subtilis from pseudomonas invasion and co-colonization of plants

Plants are colonized by a vast variety of microbes. Among them, bacteria are the most predominant and are able to adapt to environmental changes and interact with other microorganisms using a wide array of molecules, metabolic plasticity and secretion systems. One way bacteria have evolved to succeed in this competitive scenario is the formation of biofilms which provides protection to the cells, modulates the flux of signals and controls cellular differentiation. Thus, efforts are encouraged to really determine the functionality of the bacterial extracellular matrix. In this study, we have employed microbiological and microscopic techniques to study the interaction between Bacillus subtilis 3610 and Pseudomonas chlororaphis PCL1606. We demonstrate the important role of the extracellular matrix in protecting B. subtilis colonies from infiltration by Pseudomonas. Furthermore, time-lapse confocal laser scanning microscopy (CLSM) analyses of the bacterial interactions have permitted to complete the study of the bacterial behaviors and to measure bacterial expansion rates. Surprising, we find that the Pseudomonas type VI secretion system (T6SS) is required in the cell-to-cell contact with matrix-impaired B. subtilis cells, revealing a novel role for T6SS against Gram-positive bacteria. In response to P. chlororaphis infiltration, we find that B. subtilis activates sporulation and expresses motility-related genes. Confocal microscopy of the bacterial interactions using plant organs highlights the functional importance of these different bacterial strategies in their coexistence as stable bacterial communities. The findings further our understanding of the functional role played by biofilms in mediating bacterial social interactions.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Modelo de lógica difusa para pronosticar la inflación en Colombia

El presente trabajo tiene como objetivo abordar la discusión del problema inflacionario en Colombia a través de un modelo alternativo que permite realizar estimaciones en condiciones de incertidumbre esto es a través de un modelo de lógica difusa. Para esto se realiza una contextualización de las diferentes teorías que explican el proceso inflacionario y adicionalmente se plantea el por qué se considera la inflación como una variable de incertidumbre para lo cual y de acuerdo a teoría se definen las variables que afectan el ciclo inflacionario en Colombia y se realiza una estimación a través de un modelo de lógica difusa, los resultados muestran que los problemas económicos como lo es el cálculo de la inflación pueden ser tratados a través de este tipo de metodologías

Development of a control-oriented model to optimise fuel consumption and NOX emissions in a DI Diesel engine

This paper describes a predictive NOX and consumption model, which is oriented to control and optimisation of DI Diesel engines. The model applies the Response Surface Methodology following a two-step process: firstly, the relationship between engine inputs (intake charge conditions and injection settings) and some combustion parameters (peak pressure, indicated mean effective pressure and burn angles) is determined; secondly, engine outputs (NOX and consumption) are predicted from the combustion parameters using NOX and mechanical losses models. Splitting the model into two parts allows using either experimental or modelled combustion parameters, thus enhancing the model flexibility. If experimental in-cylinder pressure is used to obtain combustion parameters, the mean error of predicted NOX and consumption are 2% and 6% respectively, with a calculation time of 5.5 ms. Using modelled parameters reduces the calculation time to 1.5 ms, with a penalty in the accuracy. The model performs well in a multi-objective optimisation, reducing NOX and consumption in different amounts depending on the objective of the optimisation.The support of the Universitat Politecnica de Valencia (PAID-06-09) and Generalitat Valenciana (GV/2010/045) is greatly acknowledged.Molina, S.; Guardiola, C.; Martín Díaz, J.; Garcia Sarmiento, D. (2014). Development of a control-oriented model to optimise fuel consumption and NOX emissions in a DI Diesel engine. Applied Energy. 119:405-416. doi:10.1016/j.apenergy.2014.01.021S40541611

Potenciales flujos de inversión en renta variable en Colombia dada la implementación del esquema multifondos

El presente trabajo analiza el Modelo Multifondos implementado en el sistema privado de pensiones en Colombia y plantea los potenciales flujos de inversión que este puede llegar a tener en el mercado de renta variable. Para realizar este análisis se enuncian todos los aspectos relevantes acerca del modelo Multifondos, para lo cual se describen los aspectos legales, la situación actual del modelo en Colombia además se plantean escenarios probables de acuerdo a la evolución de estos esquemas en Chile y Perú los cuales son estudiados en el desarrollo del trabajo, esto dada la similitud de modelos al implementado en Colombia. De igual manera se analizan las reformas que actualmente adelanta el Gobierno con el objetivo de mejorar el sistema pensional. La investigación es de carácter cuantitativo la cual es fundamentada en fuentes primarias de información como lo son la Superintendencia Financiera de Colombia, la Superintendencia de Pensiones de Chile y la Superintendencia de Banca y Seguros de Perú, también se tienen presente fuentes secundaras como trabajos de investigación anteriores.This study analyzes the Multi-fund Model implemented for the private pension system in Colombia and proposes the potential investment flows of the model for the market of variable-income rates. For the conduction of this analysis all the relevant features concerning the Multifund model are taken into consideration, describing legal issues, the current situation of the model in Colombia, and proposing probable scenarios in accordance with the evolution of such schemes in Chile and Peru, which are assessed in this work given the similarities of those models with the scheme implemented in Colombia. Similarly, an analysis is made to the Bills currently discussed by the Government intending to improve the pension system. The research is of quantitative nature and supported on primary information sources such as The Finance Superintendence of Colombia, The Pensions Superintendence of Chile and the Bank and Insurance Superintendence of Peru secondary information sources used include previous research works, among others

Tse1 mobilized by T6SS of Pseudomonas induces sporulation of Bacillus via σW

The extracellular matrix and sporulation are defensive mechanisms used by Bacillus cells when they interact with Pseudomonas strains expressing a type VI secretion system (T6SS). Here, we define Tse1 as the main toxin mobilized by the Pseudomonas T6SS that triggers sporulation in Bacillus. We characterize Tse1 as a peptidoglycan hydrolase and electron microscopy analysis and the use of diverse chemical probes, let us visualize malfunction of the Bacillus cell membrane. By performing RNA-seq and immunocytochemistry analyses, we also delineate the response of Bacillus cells to Tse1, which through the coordinated actions of the extracellular sigma factor σW and the cytoplasmic histidine kinases KinA and KinB, culminates in activation of the sporulation cascade. We propose that this cellular developmental response is conserved in Bacilli to defend against the toxicity of T6SS-mobilized Tse1 effector.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Sexual Dysfunction and Quality of Life in Patients with Hidradenitis Suppurativa and Their Partners

Hidradenitis suppurativa (HS) is a chronic skin disease that profoundly affects patients’ quality of life (QoL) and sexuality. Few data are available on the impact of HS on patients’ partners. We aimed to explore the QoL and sexual function of patients’ partners and the factors associated with their impairment and to compare the QoL and sexual function of single patients and those in a stable relationship. We conducted a cross-sectional study at Hospital Universitario Virgen de las Nieves (Granada, Spain) and at theWroclaw Medical University (Wroclaw, Poland). Patients over the age of 16 years attending their scheduled follow-up and their partners, if any, were included. The Dermatology Life Quality Index (DLQI) and the Family Dermatology Life Quality Index (FDLQI) were used to estimate the QoL of patients and partners, respectively. The FSFI-6 was used to determine sexual dysfunction in women and the IIEF-5 for erectile dysfunction in men. Thirty-four single patients and twenty-eight patients in a stable relationship and their partners were included. Patients had a very large impact (DLQI 12.5 7.5) and their partners a moderate impact (FDLQI 10.3 7.1) in their QoL due to HS. Women with HS had a high prevalence of sexual dysfunction (13/32, 40.6%) and men of erectile dysfunction (19/30, 63.3%). Male partners also had a high prevalence of erectile dysfunction (10/17, 58.8%), while only one female partner had sexual dysfunction (1/11, 9.1%). Factors related to disease severity, intensity of symptoms and body mass index were associated with poorer QoL in partners and time of disease evolution with greater erectile dysfunction in male partners. In conclusion, HS not only profoundly affects the QoL and sexuality of patients but also of their partners. Several risk factors have been identified, which should be taken into account in the holistic approach of the disease

The pivotal functionality of the amyloid protein TasA in bacillus physiology and fitness

Biofilms are complex bacterial communities formed on any virtual surface and composed of cells embedded in an extracellular matrix. Studies on Bacillus subtilis have demonstrated this tissue-like structure comprised of diverse exopolymeric substances (eps) including exopolysaccharides, the protein BslA, and TasA and TapA the two main components of the amyloid fibers that confer robustness to the architecture of the biofilm. It has been demonstrated that the genetic pathways involved in formation of biofilms are active in the interaction of B. subtilis with plant surfaces. Indeed, we previously showed that surfactin acts as a self-trigger of biofilm in the plant phylloplane, which connected with the suppressive activity of B. subtilis against phytopathogenic fungi. These findings led us to hypothesize a major contribution of the extracellular matrix in the ecology of B. subtilis in the poorly explore plant phylloplane. In this work, we show that the amyloid protein TasA has a meaningful role in adhesion and biofilm formation over the plant phylloplane, however, despite the inability of the tasA mutant to form a biofilm, it still retained a similar antagonistic activity compared to the wild type strain. An in-depth transcriptomic analysis of the mutant led us to find unexpected variations in the expression levels of over 300 genes, including the overexpression of: i) production of acetoin ii) secondary metabolites and non-ribosomal peptides iii) eps and other biofilm-related components and iv) general stress, among others. These findings suggested that besides the structural role, TasA might have a regulatory function on the physiological stage of the cells. Indeed, an allele of TasA unable to restore biofilm formation allowed us to separate both functions, supporting the importance of this functional amyloid in regulating bacterial physiology and fitness.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Genetically engineering Pseudomonas strains for T6SS-dependent controlled release of effectors.

Type VI secretion systems (T6SS) are Gram-negative bacteria’s syringe-like nanomachine that injects effectors into prokaryotic and eukaryotic cells leading to the death of their target. These systems have the potential to be genetically engineered for their application in different biotechnological fields such as medicine or agriculture. As proof of concept, in this work we have genetically engineered the well-known soil-dwelling Pseudomonas putida KT2440 strain, achieving the controlled expression of related and non-related T6SS effectors. These results open a window of opportunities to secrete a wide range of molecules to different targets using this Pseudomonas strain as bacterial chassis. Specifically, this work shows promising results in the agriculture field as genetically modified P. putida KT2440 strains overexpressing T6SS-related effector Tfe2 and T6SS-non-related effector chitosanase can now inhibit bacterial and fungal strains such as the phytopathogen Botrytis cinerea.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

La protección constitucional del derecho a la verdad extrajudicial mediante el mural urbano ¿quién dio la orden? Un acto de memoria histórica del conflicto armado interno colombiano

The present investigation aims to briefly analyse the right to the truth emphasising its extrajudicial meaning and, in particular, in the historical memory that has been addressed through judgment T - 281 of 2021, in which consequently to the process instituted by the General Marcos Evangelista Pinto Lizarazo against the urban mural ¿Who gave the order? is evidenced the constitutional protection of the right to historical memory by virtue of the pronouncement of the Constitutional Court of Colombia.La presente investigación pretende analizar someramente el derecho a la verdad haciendo hincapié en su acepción extrajudicial y, en particular, en la memoria histórica que ha sido abordada mediante la sentencia T - 281 del 2021, en la que en consecuencia al proceso instaurado por el general Marcos Evangelista Pinto Lizarazo en contra del mural urbano ¿Quién dio la orden? Se evidencia la protección constitucional del derecho a la memoria histórica en virtud del pronunciamiento de la Corte Constitucional