Gene Regulatory Networks controlling Arabidopsis Root Stem Cells

Conferencia sobre aproximaciones sistémicas al conocimiento biológicoGene Regulatory Networks controlling Arabidopsis Root Stem Cells Identifying the transcription factors (TFs) and associated regulatory processes involved in stem cell regulation is key for understanding the initiation and growth of tissues and organs. Although many TFs have been described in the Arabidopsis root stem cells, a comprehensive view of the transcriptional signature of the stem cells is lacking. We used a systems biology approach to predict interactions among the genes involved in stem cell identity and maintenance. We first transcriptionally profiled four stem cell populations and developed a gene regulatory network (GRN) inference algorithm, GENIST, which combines spatial and temporal transcriptomic datasets to identify important TFs and infer gene-to-gene interactions. Our approach resulted in a map of gene interactions that orchestrates the transcriptional regulation of stem cells. In addition to linking known stem cell factors, our resulting GRNs predicted additional TFs involved in stem cell identity and maintenance. We mathematically modeled and experimentally validated some of our predicted transcription factors, which confirmed the robustness of our algorithm and our resulting networks. Our approach resulted in the finding of a factor, PERIANTHIA (PAN), which may play an important role in stem cell maintenance and QC function. We then developed an imaging system to perform in vivo, long-term imaging experiments that will be used to understand the dynamics of the regulatory interactions between PAN and its downstream TFs in a cell-specific manner. For this, we designed and 3-D printed a Multi-sample Arabidopsis Growth and Imaging Chamber (MAGIC) that provides near-physiological imaging conditions and allows high-throughput time-course imaging experiments in the ZEISS Lightsheet Z.1. We showed MAGIC’s imaging capabilities by following cell divisions, as an indicator of plant growth and development, over prolonged time periods, and demonstrated that plants imaged with our chamber undergo cell divisions for >16 times longer than those with the glass capillary system supplied by the ZEISS Z1. Future in vivo observations of the expression of PAN and its predicted downstream factors will be key to refine our model predictions and obtain information about the dynamics of the regulatory processes. Our systems biology approach illustrates the strength of integrating computational and technological tools into the experimental approaches to solve key biological questions. We anticipate that our algorithm and our approach can be applied to solve similar problems in a diverse number of systems, which can result in unsupervised predictions of gene functions and gene candidates.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A case of partial leucism in the American Barn Owl (Tyto furcata) (Temminck, 1827), from Buenos Aires province, Argentina

The diverse colorations of a birds’ plumage are due to either structural colors or pigments that are synthesized in specialized cells or incorporated through the diet. However, plumage color aberrations can occur; several cases of albinism and leucism have been reported for different bird species and some examples correspond to Strigiformes. A specimen of the American barn owl (Tyto furcata) with partial leucism was found in Carhué, Buenos Aires province. The plumage of its facial disc, tail and the ventral region was completely white; furthermore, the neck, and the primary and secondary remiges were pigmented although in a significantly lighter fashion than in normal-phenotype specimens. The rest of the body presented a normal pattern for the species.Fil: Chiale, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; ArgentinaFil: Pagano Luis Gerardo. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; Argentina. Grupo Falco; Argentin

Hyphessobrycon nicolasi (Teleostei: Characidae) a new species from the Uruguay River basin in the Mesopotamian Region, Argentina

Hyphessobrycon nicolasi is described from the Uruguay River basin in the Mesopotamian Region, Entre Ríos, Argentina. The new species can be distinguished from all congeners by the presence of a well-defined oblique and marginal black stripe on each lobe of the caudal fin. Other characters defining H. nicolasi are the possession of 1-3 teeth with 3-10 cusps on maxilla; outer premaxillary row with 2-3 small teeth, with 5 or 7 cusps; iv-vi, 27-36 anal-fin rays; 33-36 scales on the longitudinal series; two vertical dark spots on the humeral region; dorsal and anal fins dappled in black and base of caudal fin bearing conspicuous black spot; and the presence of bony hooks on the rays of dorsal, anal and caudal fins of the mature males.Fil: Miquelarena, Amalia Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Lopez, Hugo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

The state and autonomous communities in spain: A Relationship that Complicates the Task of Reducing Public Deficit

The needs imposed by the economic, ideological and institutional crisis have brought along new functions for the public sector. Nevertheless, within this new scene, the intense decentralisation of financial issues, which is characteristic of the Spanish State, makes it bad-suited for prompt and efficient compliance with decisions taken by the organisations that compose the embryonic global financial governance system and hinders tasks such as the unavoidable reduction of public deficit difficult.Crisis, Regulated capitalism, State and global financial governance, Territorial structure of the State and reduction of public deficit in Spain

No induction of antimicrobial resistance in Staphylococcus aureus and Listeria monocytogenes during continuous exposure to eugenol and citral

The aim of this study was to evaluate the adaptation response of Staphylococcus aureus, methicillin-resistant S.aureus (MRSA), and Listeria monocytogenes to the essential oil (EO), eugenol, and citral. The minimum inhibitory concentration of eugenol and citral was determined by agar dilution and microdilution. Adaptation to eugenol and citral was done by sequential exposure of the pathogens to increasing concentrations of the essential oils. The M2-A9 standard was used to determine the antibiotic susceptibility. The effect of eugenol and citral on the adherence ability was evaluated by the crystal violet assay. The impact of adaptation to eugenol on virulence was estimated using the Galleria mellonella model. No development of resistance to the components and antibiotics was observed in the adapted cells of S.aureus, MRSA, and L.monocytogenes. Eugenol and citral at subinhibitory concentration reduced the bacterial adherence. Adaptation to subinhibitory concentration of eugenol affected the virulence potential of S.aureus, MRSA, and L.monocytogenes. Eugenol and citral do not pose a risk of resistance development in a continuous mode of use. These EO components showed a high efficacy as antistaphylococcal and antilisterial biofilm agents. Adaptation at subinhibitory concentration of eugenol protected the larvae against listerial and staphylococcal infection.FCT - Fundacao para a Ciencia e Tecnologia [PEst-OE/EQB/LA0023/2013]info:eu-repo/semantics/publishedVersio

Interest rate dynamics in Kenya : commercial banks' rates and the 91 day treasury bill rate

This paper analyses the implicit dynamics underlying the interest rate structure in Kenya. For this purpose we use data on four commercial banks’ interest rates (Deposits, Savings, Lending and Overdraft) together with the 91-Day Treasury Bill rate, for the time period July 1991 – August 2010, and apply various techniques based on long-range dependence and, in particular, on fractional integration. The results indicate that all series examined are nonstationary with orders of integration equal to or higher than 1. The analysis of various spreads suggests that they also are nonstationary I(1) variables, the only evidence of mean reversion being obtained in the case of the Deposits – Treasury Bill rate spread with autocorrelated errors

Measuring Social Welfare Gains in Social Assistance Programs: An Application to European Countries

This paper aims to provide a framework for a complete assessment of the overall welfare gains resulting from social assistance programs. We make use of a social welfare function that satisfies several properties that must be considered when measuring the protection provided by these programs. We propose measuring the welfare gains that a society derives from these programs by summing up them in a way that is consistent with the standard value judgements in the income inequality literature. We also propose analytical tools that accumulate the welfare gains that, apart from having the advantage of being easy to interpret, allow the ranking of different scenarios and have an associated dominance criterion. To illustrate our approach, we measure the welfare gains caused by social assistance schemes in European countries.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech