An effort to make sense of antisense transcription in bacteria

Analysis of bacterial transcriptomes have shown the existence of a genome-wide process of overlapping transcription due to the presence of antisense RNAs, as well as mRNAs that overlapped in their entire length or in some portion of the 5'- and 3'-UTR regions. The biological advantages of such overlapping transcription are unclear but may play important regulatory roles at the level of transcription, RNA stability and translation. In a recent report, the human pathogen Staphylococcus aureus is observed to generate genome-wide overlapping transcription in the same bacterial cells leading to a collection of short RNA fragments generated by the endoribonuclease III, RNase III. This processing appears most prominently in Gram-positive bacteria. The implications of both the use of pervasive overlapping transcription and the processing of these double stranded templates into short RNAs are explored and the consequences discussed

Evaluation of the Evacuation of Essential Buildings: Interaction of Structural and Human Behaviour through Nonlinear Time-History Analysis and Agent-Based Modelling

In this article, a performance assessment of the evacuation system is established for educational buildings. Structural and geotechnical information of the building is collected and introduced into a database. A similar procedure was realized for the information related to the occupants. Using this information, a) the structural fragility and localized collapse were determined and b) the interaction of the person with the partial collapse was established. For the first aspect, nonlinear time history was used, and for the second, the agent-based modeling was applied to recreate the reaction of people that face the micro collapse. Therefore, the important results of this evaluation are: 1) To localize collapsed beans and columns that make inoperable evacuation routes, 2) to localize bottleneck areas that people concentration during evacuation, and 3) quantification of affected people, in terms of persons caught up in the building that cannot evacuate

Deciphering the light signal transduction mechanism in Staphylococcus aureus

Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii have been recognized by the WHO and the CDC as critical human pathogens. These microorganisms belong to the ESKAPE group, so named since they are capable of "escaping" antibiotic treatments. The infections caused by these pathogens result in a dramatic increase in the costs of medical care. Previous results from our laboratory have shown that these microorganisms can sense and respond to light. In S. aureus, light has been shown to modulate important pathogenicity determinants such as alpha toxin-dependent hemolysis, as well as virulence in an epithelial infection model, which could have implications in human infections. Light also regulates persistence, metabolism, and the ability to kill competitors such as C. albicans, in this microorganism. To our knowledge, the ability of S. aureus to sense and respond to light constitutes a newly described physiological trait. These pathogens could sense light to synchronize their behavior with the circadian rhythm of their hosts, likely as a strategy to optimize infection development. Identification of the photoreceptors involved in light sensing in S. aureus would provide important insights into the light signal transduction cascade. Despite no traditional photoreceptors were found encoded in its genome, we identified the presence of three putative proteins containing GAF domains. GAF domains have been shown to be part of phytochromes and cyanobacteriochromes along with other domains such as PHY and PAS. While in two of them the GAF domain encompasses the full-length protein sequence, suggesting a new photoreceptor architecture, the last one harbors a GAF N-terminal domain associated with a C-terminal histidine kinase. The genomic environment of each putative photoreceptor was determined, and genes such as LuxR, involved in a quorum-sensing regulation; and DegU, identified as a response regulator of bacterial motility, virulence and biofilm formation, were found in their close proximity. Recent results from our group show that motility in S. aureus is not only modulated by blue light, but also by red and green lights. This is compatible with multiple GAF photoreceptors as they exist in two thermally stable states interconvertible by light, absorbing in different regions of the spectrum. Moreover, the presence of three cysteine residues were observed, residue shown to be essential for binding of the bilin chromophore. In this sense, it is interesting to note that S. aureus produces Staphylobilin as a product of heme metabolism. In addition, we amplified the DNA fragments encoding these putative photoreceptors from S. aureus USA300 strain, and subcloned them into the expression vector pET-TEV, to corroborate that they are active photoreceptors upon light absorption. Finally, proteomic results are discussed which suggest new pathways modulated by light in S. aureus such as cell wall synthesis and recycling.Fil: Arana, N. A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro de Estudios Fotosintéticos y Bioquímicos. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Centro de Estudios Fotosintéticos y Bioquímicos; ArgentinaFil: Müller, G. L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro de Estudios Fotosintéticos y Bioquímicos. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Centro de Estudios Fotosintéticos y Bioquímicos; ArgentinaFil: Mussi, María Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro de Estudios Fotosintéticos y Bioquímicos. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Centro de Estudios Fotosintéticos y Bioquímicos; ArgentinaLVII SAIB Meeting; XVI SAMIGE MeetingArgentinaSociedad Argentina De Investigación Bioquímica Y Biología MolecularSociedad Argentina de Microbiología Genera

An analysis of the variables that provide a supply chain with sustainable competitiveness

Objeto: Una cadena de suministro (CS) ágil, adaptable y alineada (Triple A) parece clave para la obtención de ventajas competitivas sostenibles. Sin embargo, hay escasa investigación previa sobre el tema, observándose incluso discrepancias a nivel conceptual. Por ello, el objetivo del presente trabajo es proponer un marco de referencia que determine las dimensiones y factores que definen la agilidad, adaptabilidad y alineación en la CS y facilite a los gestores e investigadores la evaluación del estado de la misma en lo que respecta a estas variables, así como el desarrollo de investigaciones empíricas que determinen su impacto en el rendimiento. Diseño/metodología/enfoque: Se realiza una revisión sistemática de bibliografía en revistas especializadas en Dirección de Operaciones, Logística, Administración y Gestión de la Cadena de Suministro utilizando la base de datos ABI/Inform. Los artículos obtenidos fueron revisados, seleccionándose los relevantes para este estudio. Con ellos se realizó un análisis cualitativo que nos llevó a la consecución del objetivo planteado. Aportaciones y resultados: En la presente investigación se establecen y agrupan, por primera vez, las definiciones, dimensiones y factores de la triple A en la CS, ofreciendo un marco conceptual que apoyará a investigadores y gestores a evaluar el desempeño de la CS. Aunque los artículos que analizan alguna de estas variables van en aumento, siguen siendo escasos. La agilidad es la variable más estudiada, siendo la adaptabilidad la menos analizada. Limitaciones / implicaciones: Se propone un marco de referencia teórico para la triple A en la CS construido a partir de estudios previos que no evalúan de manera conjunta las tres variables. El modelo será analizado empíricamente en futuras investigaciones. Originalidad / Valor añadido: La escasez de trabajos sobre agilidad, adaptabilidad y alineación en la CS, así como la falta de consenso respecto a las dimensiones y factores que las definen, hacen necesarios estudios como el que se presenta.Purpose: An agile, adaptable and aligned (Triple A) supply chain (SC) would seem to be key to obtaining sustainable competitive advantages. Little previous research has been done into the topic, however, and there are even discrepancies on the conceptual level. For this reason this study aims to propose a reference framework to determine the dimensions and factors that define agility, adaptability and alignment in the SC and to facilitate both the evaluation of its state by managers and researchers with respect to these variables and also the development of empirical research that determines its impact on performance. Design/methodology: A systematic literature review was carried out of specialist Operations Management, Logistics, Management and Supply Chain Management journals using the ProQuest (Abi/Inform Global) database. The articles retrieved were examined and those that were relevant for this study were selected. Using these, a qualitative analysis was done that led to the proposed goal being achieved. Findings: This study sets out the definitions, dimensions and factors of the three variables and groups them together for the first time, thus providing a solid conceptual frame. Although the number of articles that analyse one or other of the variables is growing, it is still low. Agility is the variable on which most research has been done, while adaptability is the least analysed. Research limitations/implications: A theoretical reference framework is proposed for the Triple A in the SC based on earlier studies which do not discuss the joint effect of three variables, as a result of which there is no tested theoretical base. The model will be analysed empirically in future research. Originality/value: The lack of papers on agility, adaptability and alignment in the supply chain and the lack of a consensus regarding the dimensions and factors to define them reveal a need for studies such as this.Peer Reviewe

Mineral prices persistence and the development of a new energy vehicle industry in China: A fractional integration approach

In this paper we examine price persistence in a set of minerals critical for the production of new energy vehicles. We implement techniques based on fractional integration also allowing for non-linearities and structural breaks at unknown periods of time. The results show that the series are generally very persistent, with orders of integration equal to or higher than 1 in practically all cases. The only exceptions being cobalt, tin and zinc if breaks are permitted and only for a given subsample. These findings are extremely relevant to initiate a discussion about the challenges that the new energy vehicle industry faces in China. China's government has already enforced some relevant initiatives to stabilise prices, but we conclude that additional measures will be necessary considering the high degree of uncertainty of certain supply-demand factors.Prof. Luis A. Gil-Alana gratefully acknowledges financial support from the MINEIC-AEI-FEDER PID2020-113691RB-I00 project from ‘Ministerio de Economía, Industria y Competitividad’ (MINEIC), ‘Agencia Estatal de Investigación’ (AEI) Spain and ‘Fondo Europeo de Desarrollo Regional’ (FEDER). He also acknowledges support from an internal Project of the Universidad Francisco de Vitoria, Madrid, Spain