Assessment of a Modified Hydrocyclone with Ultrasonic Assistance for Nickel Powder Electrochemical Production

An electrochemical reactor based on a modified hydrocyclone with ultrasonic assistance is examined with the purpose of analyzing the continuous production of nickel powder from dilute solutions simulating industrial wastewaters containing nickel. Under operating conditions, nickel deposition takes place under mass-transfer control and the helical flow inside the reactor generates a high mass-transfer coefficient, thus improving the removal of metal ions. The application of ultrasound is crucial for the detachment of the electrodeposited nickel, which allows its recovery as a metal powder. The best result was achieved at a current density of 5368 A m?2 and 60 °C yielding a nickel powder fraction obtained from the spigot of the device higher than 90%. The gravimetric current efficiency and the specific energy consumption were 33.4% and 23.8 kW h kg?1, respectively, for anexperiment lasting 13 min. The nickel particles are of high purity and dendritic nature with an average size of 22.9 μm.Fil: González Pérez, Omar. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Electroquímica Aplicada e Ingeniería Electroquímica; ArgentinaFil: Bisang, Jose Maria. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Electroquímica Aplicada e Ingeniería Electroquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

Chloroplast damage induced by the inhibition of fatty acid synthesis triggers autophagy in chlamydomonas

Fatty acids are synthesized in the stroma of plant and algal chloroplasts by the fatty acid synthase complex. Newly synthesized fatty acids are then used to generate plastidial lipids that are essential for chloroplast structure and function. Here, we show that inhibition of fatty acid synthesis in the model alga Chlamydomonas reinhardtii activates autophagy, a highly conserved catabolic process by which cells degrade intracellular material under adverse conditions to maintain cell homeostasis. Treatment of Chlamydomonas cells with cerulenin, a specific fatty acid synthase inhibitor, stimulated lipidation of the autophagosome protein ATG8 and enhanced autophagic flux. We found that inhibition of fatty acid synthesis decreased monogalactosyldiacylglycerol abundance, increased lutein content, down-regulated photosynthesis, and increased the production of reactive oxygen species. Electron microscopy revealed a high degree of thylakoid membrane stacking in cerulenin-treated cells. Moreover, global transcriptomic analysis of these cells showed an up-regulation of genes encoding chloroplast proteins involved in protein folding and oxidative stress and the induction of major catabolic processes, including autophagy and proteasome pathways. Thus, our results uncovered a link between lipid metabolism, chloroplast integrity, and autophagy through a mechanism that involves the activation of a chloroplast quality control system.Ministerio de Economía y Competitividad BFU2015-68216-PJunta de Andalucía CVI-7336, BIO2015-74432-JI

Seized Objects: Tools to Structure the Material and Social Selves

During the existence of some objects occurred representations that mark not only a transit between different individuals and contexts, but the creation of interpersonal bonds linked to memories, feelings and wishes, among others, that extend their service life beyond economic dynamics, this phenomenon has been called reuse. Three types of object’s dynamics are identified in this study: mutable objects dynamic, which represent a scenario of objects creation and use by societies in transition; located objects dynamic, which falls into the principles of family social reproduction; and seized objects dynamic, which serve in the construction of the material and social Selves of individuals. This last type of dynamic will be the main subject of the study. Under the dynamics of reuse, some forms of social and environmental sustainability are visualized, due to the construction of objects exchange networks

Arcs and jets on toric singularities and quasi-ordinary singularities

Abstracts from the workshop held January 29--February 4, 2006Depto. de Álgebra, Geometría y TopologíaFac. de Ciencias MatemáticasTRUEpu

Phosphorus Availability Regulates TORC1 Signaling via LST8 in Chlamydomonas

Target of rapamycin complex 1 (TORC1) is a central regulator of cell growth. It balances anabolic and catabolic processes in response to nutrients, growth factors, and energy availability. Nitrogen- and carbon-containing metabolites have been shown to activate TORC1 in yeast, animals, and plants. Here, we show that phosphorus (P) regulates TORC1 signaling in the model green alga Chlamydomonas (Chlamydomonas reinhardtii) via LST8, a conserved TORC1 subunit that interacts with the kinase domain of TOR. P starvation results in a sharp decrease in LST8 abundance and downregulation of TORC1 activity. A hypomorphic lst8 mutation resulted in decreased LST8 abundance, and it both reduced TORC1 signaling and altered the cellular response to P starvation. Additionally, we found that LST8 levels and TORC1 activity were not properly regulated in a mutant defective in the transcription factor PSR1, which is the major mediator of P deprivation responses in Chlamydomonas. Unlike wild-type cells, the psr1 mutant failed to downregulate LST8 abundance and TORC1 activity when under P limitation. These results identify PSR1 as an upstream regulator of TORC1 and demonstrate that TORC1 is a key component in P signaling in Chlamydomonas.España Ministerio de Economía y Competitividad (grants BFU2015-68216-P and PGC2018-099048- B-100 to J.L.C. and grant BIO2015-74432-JIN to M.E.P.-P.)National Science Foundation (CAREER award MCB-1552522 to L.M.H. and grant MCB-1616820 to J.G.U.)European Commission (grant number 750996

Deciphering the function and evolution of the TOR signaling pathway in microalgae

Microalgae constitute a highly diverse group of photosynthetic microorganisms that are widely distributed on Earth. The rich diversity of microalgae arose from endosymbiotic events that took place early in the evolution of eukaryotes and gave rise to multiple lineages including green algae, the ancestors of land plants. In addition to their fundamental role as the primary source of marine and freshwater food chains, microalgae are essential producers of oxygen in the planet and a major biotechnological target for sustainable biofuel production and CO2 mitigation. Microalgae integrate light and nutrient signals to regulate cell growth. Recent studies identified the target of rapamycin (TOR) kinase as central regulator of cell growth and nutrient sensor in microalgae. TOR promotes protein synthesis and regulates processes that are induced under nutrient stress such as autophagy and the accumulation of triacylglycerol and starch. A detailed analysis of representative genomes from the entire microalgal lineage revealed the high conservation of central components of the TOR pathway likely present in the last eukaryotic common ancestor and the loss of specific TOR signaling elements at an early stage in the evolution of microalgae. Here we examine the evolutionary conservation of TOR signaling components in diverse microalgae and discuss recent progress on the study of this signaling pathway in these organisms.Ministerio de Ciencia y Tecnología PGC2018-099048-B-I00, PID2019-110080GB-I0

Separation of phthalates by cyclodextrin modified micellar electrokinetic chromatography. Quantitation in perfumes.

A new CE method has been developed for the simultaneous separation of a group of parent phthalates. Due to the neutral character of these compounds, the addition of several bile salts as surfactants (sodium cholate (SC), sodium deoxycholate (SDC), sodium taurodeoxycholate (STDC), sodium taurocholate (STC)) to the separation buffer was explored showing the high potential of SDC as pseudostationary phase. However, the resolution of all the phthalates was not achieved when employing only this bile salt as additive, being necessary the addition of neutral cyclodextrins (CD) and organic modifiers to the separation media. The optimized cyclodextrin modified micellar electrokinetic chromatography (CD-MEKC) method consisted of the employ of a background electrolyte (BGE) containing 25 mM beta-CD-100 mM SDC in a 100 mM borate buffer (pH 8.5) with a 10% (v/v) of acetonitrile, employing a voltage of 30 kV and a temperature of 25 degrees C. This separation medium enabled the total resolution of eight compounds and the partial resolution of two of the analytes, di-n-octyl phthalate (DNOP) and diethyl hexyl phthalate (DEHP) (Rs similar to 0.8), in only 12 min. The analytical characteristics of the developed method were studied showing their suitability for the determination of these compounds in commercial perfumes. In all the analyzed perfumes the most common phthalate was diethyl phthalate (DEP) that appeared in ten of the fifteen analyzed products. Also dimethyl phthalate (DMP), diallyl phthalate (DAP), dicyclohexyl phthalate (DCP), and di-n-pentyl phthalate (DNPP) were found in some of the analyzed samples. (C) 2013 Elsevier B.V. All rights reserved

La teledetección desde el espacio. Aplicaciones en Geografía Física

Se analiza que es la teledetección como herramienta dentro del ambito de la geografía, y con especial incidencia en su uso territorial en Geografía Física.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech