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Protein Degradation Regulates Phospholipid Biosynthetic Gene Expression in Saccharomyces cerevisiae
Transcriptional regulation of most phospholipid biosynthetic genes in Saccharomyces cerevisiae is coordinated by inositol and choline. Inositol affects phosphatidic acid (PA) intracellular levels. Opi1p interacts physically with PA and is the main repressor of the phospholipid biosynthetic genes. It is localized in the endoplasmic reticulum (ER) bound to the ER membrane protein Scs2p. When PA levels drop, Opi1p is translocated into the nucleus repressing most phospholipid biosynthetic genes. The OPI1 locus was identified in a screen looking for overproduction and excretion of inositol (Opi-). Opi- mutants are generally associated with a defect in repression of the phospholipid biosynthetic genes. Using a conditional shut-off library we conducted a screen that identified 121 genes with an Opi- phenotype. These genes identified pathways previously unknown to regulate the phospholipid genes like the Ubiquitin/Proteasome system. It also identified the essential subunits of NuA4 HAT. Genes involved in the Ubiquitin/Proteasome system and NuA4 HAT were tested for a repression defect in the most highly regulated phospholipid biosynthetic genes, INO1. Neither mutant identified from these pathways showed a repression defect under repressing conditions. Phospholipid biosynthetic genes are also growth phase regulated that is under activating conditions (no inositol) INO1 is active, but when cells reach the stationary phase INO1 is repressed. Both NuA4 HAT and Ubiquitin/Proteasome genes showed a repression defect at the stationary phase of the cellular growth suggesting that these biological processes are responsible for the regulation of INO1 at the stationary phase of the cellular growth
A Model-Based Framework for the Smart Manufacturing of Polymers
It is hard to point a daily activity in which polymeric materials or plastics are not involved. The synthesis of polymers occurs by reacting small molecules together to form, under certain conditions, long molecules. In polymer synthesis, it is mandatory to assure uniformity between batches, high-quality of end-products, efficiency, minimum environmental impact, and safety. It remains as a major challenge the establishment of operational conditions capable of achieving all objectives together. In this dissertation, different model-centric strategies are combined, assessed, and tested for two polymerization systems.
The first system is the synthesis of polyacrylamide in aqueous solution using potassium persulfate as initiator in a semi-batch reactor. In this system, the proposed framework integrates nonlinear modelling, dynamic optimization, advanced control, and nonlinear state estimation. The objectives include the achievement of desired polymer characteristics through feedback control and a complete motoring during the reaction. The estimated properties are close to experimental values, and there is a visible noise reduction. A 42% improvement of set point accomplishment in average is observed when comparing feedback control combined with a hybrid discrete-time extended Kalman filter (h-DEKF) and feedback control only. The 4-state geometric observer (GO) with passive structure, another state estimation strategy, shows the best performance. Besides achieving smooth signal processing, the observer improves 52% the estimation of the final molecular weight distribution when compared with the h-DEKF.
The second system corresponds to the copolymerization of ethylene with 1,9-decadiene using a metallocene catalyst in a semi-batch reactor. The evaluated operating conditions consider different diene concentrations and reaction temperatures. Initially, the nonlinear model is validated followed by a global sensitivity analysis, which permits the selection of the important parameters. Afterwards, the most important kinetic parameters are estimated online using an extended Kalman filter (EKF), a variation of the GO that uses a preconditioner, and a data-driven strategy referred as the retrospective cost model refinement (RCMR) algorithm. The first two strategies improve the measured signal, but fail to predict other properties. The RCMR algorithm demonstrates an adequate estimation of the unknown parameters, and the estimates converge close to theoretical values without requiring prior knowledge
Extensive Sensitivity Analysis and Parallel Stochastic Global Optimization Using Radial Basis Functions of Integrated Biorefineries under Operational Level Uncertainties
This work presents a decision-making framework for global optimization of detailed renewable energy processes considering technological uncertainty. The critical uncertain sources are identified with an efficient computational method for global sensitivity analysis, and are obtained in two different ways, simultaneously and independently per product pathway respect to the objective function. For global optimization, the parallel stochastic response surface method developed by Regis & Shoemaker (2009) is employed. This algorithm is based on the multi-start local metric stochastic response surface method explored by the same authors (2007a). The aforementioned algorithm uses as response surface model a radial basis function (RBF) for approximating the expensive simulation model. Once the RBF’s parameters are fitted, the algorithm selects multiple points to be evaluated simultaneously. The next point(s) to be evaluated in the expensive simulation are obtained based on their probability to attain a better result for the objective function. This approach represents a simplified oriented search. To evaluate the efficacy of this novel decision-making framework, a hypothetical multiproduct lignocellulosic biorefinery is globally optimized on its operational level. The obtained optimal points are compared with traditional optimization methods, e.g. Monte-Carlo simulation, and are evaluated for both proposed types of uncertainty calculated
Arabidopsis thaliana: A model host plant to study plant-pathogen interaction using Chilean field isolates of Botrytis cinerea
http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000200004&lng=es&nrm=isoOne of the fungal pathogens that causes more agriculture damage is Botrytis cinerea. Botrytis is a constant threat to crops because the fungus infects a wide range of host species, both native and cultivated. Furthermore, Botrytis persists on plant debris in and on the soil. Some of the most serious diseases caused by Botrytis include gray mold on vegetables and fruits, such as grapes and strawberries. Botrytis also causes secondary soft rot of fruits and vegetables during storage, transit and at the market.
In many plant-pathogen interactions, resistance often is associated with the deposition of callose, accumulation of autofluorescent compounds, the synthesis and accumulation of salicylic acid as well as pathogenesis-related proteins. Arabidopsis thaliana has been used as a plant model to study plant-pathogen interaction. The genome of Arabidopsis has been completely sequenced and this plant serves as a good genetic and molecular model. In this study, we demonstrate that Chilean field isolates infect Arabidopsis thaliana and that Arabidopsis subsequently activates several defense response mechanisms associated with a hypersensitive response. Furthermore, we propose that Arabidopsis may be used as a model host species to analyze the diversity associated with infectivity among populations of Botrytis cinerea field isolates
Responding to the Popular Demand: Itinerary for the Socio-Political Learning of Situated Agroecologies in Chile
Agroecology has proven to be successful in responding to the demands and needs of a
collective due to the relevance of its approach and proposals, which are built collaboratively between
all the actors under a specific context that focuses on the actions developed. This is facilitated when
spaces of horizontal interaction are generated through dialogues between different perspectives
and experiences. In this perspective, agroecological training in higher education, i.e., university
level, requires structural changes that go beyond the incorporation of technical content. Based on a
critical documentary analysis of the records generated in the implementation of teaching innovation
projects, the learning itinerary in agroecology is presented, consisting of four certifications based
on transformational learning and supported by active methodologies. The potentialities, including
marketing potential, of the proposed learning itinerary relate to curricular design, the articulation of
the itinerary, the suitability of the learning methodologies used, the performance of the teachers, and
the participation of the students. It is concluded that the implementation of flexible itineraries allows
for addressing the transformation processes necessary for an agroecological transition in which we
see a convergence of students’ skills, the learning objectives, and the requirements of the various
actors with which they interact.Universidad de Santiago de Chile USA 155
Estudio de viabilidad de un portafolio de proyectos de servicios de automatización de edificaciones en Colombia
En los últimos 10 años, se ha vivido una evolución tecnológica sin precedentes, y el hogar no ha sido ajeno a esta revolución -- La domótica, entendida como la automatización de las funciones típicas del hogar, ha seguido este avance tecnológico y ha comenzado a ser apreciada como algo normal y deseable dentro de los elementos de un hogar -- En Colombia, la adopción de la domótica es aún un mercado nuevo -- Los actuales consumidores nacionales de estos servicios son reducidos, y el acceso a esta tecnología es considerada como de alto precio por la mayoría de la población e inclusive, innecesario por muchos -- Sin embargo, la disponibilidad de esta tecnología a nivel mundial y la facilidad para ser distribuida y adaptada localmente, posibilita ingresar en este nuevo mercado en el país -- Con este fin, se diseñó un portafolio de proyectos de automatización del hogar, y se realizó un análisis sectorial, técnico, legal, administrativo, financiero, de mercado y de riesgos, que permitió analizar la viabilidad de la ejecución del portafolio de proyectos propuest
Nodal involvement evaluation in advanced cervical cancer: a single institutional experience
Purpose: To assess the usefulness of different imaging techniques in the detection of nodal involvement in patients with advanced
cervical carcinoma. Moreover, to analyze the correlation between the presurgical (FIGO) and postsurgical (pTNM) staging classifications.
Materials and Methods: All patients diagnosed with advanced cervical cancer (FIGO Stages IIB-IV) from 2005 to 2012 were
selected. The medical charts of 51 patients that underwent presurgical assessment with posterior surgical staging by means of paraaortic
lymphadenectomy, were reviewed. Nodal status assessment by computed tomography scan (CT scan), magnetic resonance
imaging (MRI), positron emission tomography (PET), and sonography was compared, as well as the size given in imaging techniques
compared to the final pathologic report information. Results: Presurgical analysis by CT scan, MRI, PET, and sonography showed
pelvic nodal involvement in 51.3% of patients, and para-aortic involvement in 30.8% of cases. CT scan showed positive pelvic nodes
in 35% of cases, but pathologic confirmation was observed in just 17.6% of cases. However, MRI resulted in higher rates of up to
48.8% of cases. Concerning para-aortic nodal involvement, CT scan showed positive nodes in 25% of cases, MRI in 3.2% of cases,
and the pathologic report in 15.6% of cases. The authors found significant differences between staging groups among both classifications
(FIGO vs. pTNM; p < 0.001). Eight cases (15.7%) were understaged by FIGO classification. Conclusions: Despite all imaging
techniques available, none has demonstrated to be efficient enough to avoid the systematic study of para-aortic nodal status by
means of surgical evaluatio
Interactions of host miRNAs in the flavivirus 3´UTR genome:From bioinformatics predictions to practical approaches
The genus Flavivirus of the Flaviviridae family includes important viruses, such as Dengue, Zika, West Nile, Japanese encephalitis, Murray Valley encephalitis, tick-borne encephalitis, Yellow fever, Saint Louis encephalitis, and Usutu viruses. They are transmitted by mosquitoes or ticks, and they can infect humans, causing fever, encephalitis, or haemorrhagic fever. The treatment resources for these diseases and the number of vaccines available are limited. It has been discovered that eukaryotic cells synthesize small RNA molecules that can bind specifically to sequences present in messenger RNAs to inhibit the translation process, thus regulating gene expression. These small RNAs have been named microRNAs, and they have an important impact on viral infections. In this review, we compiled the available information on miRNAs that can interact with the 3’ untranslated region (3’UTR) of the flavivirus genome, a conserved region that is important for viral replication and translation
Comparación de la densidad y actividad bacteriana fijadora libre de nitrógeno entre tres usos de suelo (Cuenca del Otún, Risaralda)
Se determinó el efecto del uso del suelo cultivos de cebolla Allium fistulosum y plantaciones de pino Pinus patula sobre la densidad y la actividad microbiana de bacterias fijadoras libres de nitrógeno (BFNL) en suelos de la cuenca del Otún, Risaralda, teniendo como control el bosque subandino. Se realizaron dos muestreos con cinco meses de intervalo entre sí (julio y diciembre de 2008), tomando 27 muestras por muestreo para un total de 54 muestras. Las BFNL fueron cultivadas en NFMM para determinar su densidad en UFC/g y la actividad microbiana fijadora libre de nitrógeno. Se realizaron determinaciones de características ambientales y pruebas fisicoquímicas de los tres usos de suelo, para conocer la relación de estas con la densidad y la actividad microbiana de las BFNL. Se encontró que no habían diferencias significativas en la densidad y la actividad bacteriana fijadora libre de nitrógeno entre los tres usos de suelo y se encontró que las variables fisicoquímicas y ambientales que más implicación tuvieron sobre la densidad y la actividad de las BFNL fueron los agregados de 1.18 mm, 54 ?m, <54 ?m, temperatura del suelo y ambiental mínima, conductividad eléctrica, materia orgánica, limo y arena. Con base en5 que no se encontraron diferencias significativas entre la densidad y actividad microbiana de las BFNL en los tres usos de suelo, se sugiere que este grupo funcional no sería un buen indicador tardío del efecto de estos usos de suelo. Para estudios posteriores se recomienda utilizar métodos que permitan cuantificar la actividad fijadora libre de nitrógeno, además de realizar estudios en diferentes épocas climáticas para establecer la influencia de factores como la precipitación, sobre la densidad y actividad de las BFNL.Microbiólogo (a) IndustrialPregrad
Sin razones del derecho.
El presente ensayo pretende abarcar algunos puntos de vista (no todos), en lo concerniente a la Razón de la Sinrazón del Derecho. Sí, por decirlo así, se puede o ha podido pensarse en una razón del Derecho, por qué cuánto más no, en una “sinrazón” o más bien unas cuántas “sinrazones” del mismo
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