Fundamental analysis Peruvian non listed company - Real Pharma

The present case study seeks to guide the potential investor through the process of analyzing the financial situation of a company to be able to make an adequate deal for an acquisition or invest. The case intends to follow a top-down analysis structure as follows: a macroeconomic analysis, which covers the gross domestic product, inflation and others; followed by a sectorial study, which comprises the study of competitors, suppliers, clients, and others; and the company?s analysis both from a financial and non-financial perspective.El presente estudio de caso busca guiar al inversionista potencial a trav?s del proceso de an?lisis de la situaci?n financiera de una empresa para poder hacer un trato adecuado para una adquisici?n o inversi?n. El caso pretende seguir una estructura de an?lisis descendente de la siguiente manera: un an?lisis macroecon?mico, que cubre el producto interno bruto, la inflaci?n y otros; seguido de un estudio sectorial, que comprende el estudio de competidores, proveedores, clientes y otros; y el an?lisis de la compa??a tanto desde una perspectiva financiera como no financiera

Condrodisplasia metafisiaria tipo schmid

Revisar bases genotípicas y fenotípicas de la condrodisplasia metafisiaria tipo Schmid

Development of a New Method for the Determination of Manganese, Cadmium, Mercury and Lead in Whole Blood and Amniotic Fluid by Inductively Coupled Plasma Mass Spectrometry

Environmental exposure to metals among women, revealed their adverse effects on pregnancy. During this stage, blood levels of some metals increase so research on heavy metals transference from the mother’s blood to the developing foetus is of special interest and much attention has been paid to this matter. The amniotic fluid can be considered as a valuable marker of this prenatal exposure to exogenous factors. The aim of this study was to develop a method for the simultaneous determination of Mn, Cd, Hg, and Pb in whole maternal blood and amniotic fluid by ICP-MS. Strategies were given to minimise memory effects related to mercury and two widespread digestion procedures (open-vessel and microwave-assisted) were compared. Several quality controls, such as methodological and reagent blanks, spiked samples and duplicates were used to test the goodness of the developed method. Once optimised, the method was applied for the monitoring of Mn, Cd, Hg and Pb in 15 maternal blood and amniotic fluid samples obtained at delivery after informed consent. This study establishes that heavy metals pass into and accumulate in amniotic fluid and maternal blood. Thus, mean concentrations of Mn were similar in the two biological fluids studied, 21.6 ng/mL in maternal blood and 20.5 ng/mL in amniotic fluid. Mean Cd and mercury levels in blood and amniotic fluid were 1.3 and 6.3 ng/mL and 3.4 and 3.8 ng/mL, respectively. Concentrations of Pb were 16.4 ng/mL in blood and 13.7 ng/mL in amniotic fluid. Further studies are needed to evaluate the long-term health effects derived from this exposure.Plan Propio of the University of SevilleFundación Farmacéutica Avenzoa

Protein kinase GCN2 mediates responses to glyphosate in Arabidopsis

Background: The increased selection pressure of the herbicide glyphosate has played a role in the evolution of glyphosate-resistance in weedy species, an issue that is becoming a threat to global agriculture. The molecular components involved in the cellular toxicity response to this herbicide at the expression level are still unidentified. Results: In this study, we identify the protein kinase GCN2 as a cellular component that fosters the action of glyphosate in the model plant Arabidopsis thaliana. Comparative studies using wild-type and gcn2 knock-out mutant seedlings show that the molecular programme that the plant deploys after the treatment with the herbicide, is compromised in gcn2. Moreover, gcn2 adult plants show a lower inhibition of photosynthesis, and both seedlings and adult gcn2 plants accumulate less shikimic acid than wild-type after treatment with glyphosate. Conclusions: These results points to an unknown GCN2-dependent factor involved in the cascade of events triggered by glyphosate in plants. Data suggest either that the herbicide does not equally reach the target-enzyme in a gcn2 background, or that a decreased flux in the shikimate pathway in a gcn2 plants minimize the impact of enzyme inhibition.p This work was mainly supported by the Universidad Politecnica de Valencia (PAID2011-16) and the Ministerio Espanol de Ciencia y Tecnologia (BFU2011-22526). The work was partially supported through a grant from the Ministerio Espanol de Ciencia y Tecnologia (AGL-2010-18621).Faus, I.; Zabalza Ostos, AM.; Santiago, J.; González Nebauer, S.; Royuela, M.; Serrano, R.; Gadea, J. (2015). Protein kinase GCN2 mediates responses to glyphosate in Arabidopsis. BMC Plant Biology. 15(14). https://doi.org/10.1186/s12870-014-0378-0S1514Basu, C., Halfhill, M. D., Mueller, T. C., & Stewart, C. N. (2004). Weed genomics: new tools to understand weed biology. Trends in Plant Science, 9(8), 391-398. doi:10.1016/j.tplants.2004.06.003Délye, C. (2012). Unravelling the genetic bases of non-target-site-based resistance (NTSR) to herbicides: a major challenge for weed science in the forthcoming decade. Pest Management Science, 69(2), 176-187. doi:10.1002/ps.3318Powles, S. B., & Yu, Q. (2010). Evolution in Action: Plants Resistant to Herbicides. Annual Review of Plant Biology, 61(1), 317-347. doi:10.1146/annurev-arplant-042809-112119Ge, X., d’ Avignon, D. A., Ackerman, J. J. H., Collavo, A., Sattin, M., Ostrander, E. L., … Preston, C. (2012). Vacuolar Glyphosate-Sequestration Correlates with Glyphosate Resistance in Ryegrass (Lolium spp.) from Australia, South America, and Europe: A31P NMR Investigation. Journal of Agricultural and Food Chemistry, 60(5), 1243-1250. doi:10.1021/jf203472sDuke, S. O., & Powles, S. B. (2008). Glyphosate: a once-in-a-century herbicide. Pest Management Science, 64(4), 319-325. doi:10.1002/ps.1518De María, N., Becerril, J. M., García-Plazaola, J. I., Hernández, A., de Felipe, M. R., & Fernández-Pascual, M. (2006). New Insights on Glyphosate Mode of Action in Nodular Metabolism:  Role of Shikimate Accumulation. Journal of Agricultural and Food Chemistry, 54(7), 2621-2628. doi:10.1021/jf058166cZulet, A., Gil-Monreal, M., Villamor, J. G., Zabalza, A., van der Hoorn, R. A. L., & Royuela, M. (2013). Proteolytic Pathways Induced by Herbicides That Inhibit Amino Acid Biosynthesis. PLoS ONE, 8(9), e73847. doi:10.1371/journal.pone.0073847Ahsan, N., Lee, D.-G., Lee, K.-W., Alam, I., Lee, S.-H., Bahk, J. D., & Lee, B.-H. (2008). Glyphosate-induced oxidative stress in rice leaves revealed by proteomic approach. Plant Physiology and Biochemistry, 46(12), 1062-1070. doi:10.1016/j.plaphy.2008.07.002Lu, W., Li, L., Chen, M., Zhou, Z., Zhang, W., Ping, S., … Lin, M. (2013). Genome-wide transcriptional responses of Escherichia coli to glyphosate, a potent inhibitor of the shikimate pathway enzyme 5-enolpyruvylshikimate-3-phosphate synthase. Mol. BioSyst., 9(3), 522-530. doi:10.1039/c2mb25374gServaites, J. C., Tucci, M. A., & Geiger, D. R. (1987). Glyphosate Effects on Carbon Assimilation, Ribulose Bisphosphate Carboxylase Activity, and Metabolite Levels in Sugar Beet Leaves. Plant Physiology, 85(2), 370-374. doi:10.1104/pp.85.2.370Zhu, J., Patzoldt, W. L., Shealy, R. T., Vodkin, L. O., Clough, S. J., & Tranel, P. J. (2008). Transcriptome Response to Glyphosate in Sensitive and Resistant Soybean. Journal of Agricultural and Food Chemistry, 56(15), 6355-6363. doi:10.1021/jf801254eMarc, J., Mulner-Lorillon, O., & Bellé, R. (2004). Glyphosate-based pesticides affect cell cycle regulation. Biology of the Cell, 96(3), 245-249. doi:10.1016/j.biolcel.2003.11.010Wek, R. C., Jiang, H.-Y., & Anthony, T. G. (2006). Coping with stress: eIF2 kinases and translational control. Biochemical Society Transactions, 34(1), 7-11. doi:10.1042/bst0340007Hinnebusch, A. G. (2005). TRANSLATIONAL REGULATION OFGCN4AND THE GENERAL AMINO ACID CONTROL OF YEAST. Annual Review of Microbiology, 59(1), 407-450. doi:10.1146/annurev.micro.59.031805.133833Zhang, Y., Dickinson, J. R., Paul, M. J., & Halford, N. G. (2003). Molecular cloning of an arabidopsis homologue of GCN2, a protein kinase involved in co-ordinated response to amino acid starvation. Planta, 217(4), 668-675. doi:10.1007/s00425-003-1025-4Zhang, Y., Wang, Y., Kanyuka, K., Parry, M. A. J., Powers, S. J., & Halford, N. G. (2008). GCN2-dependent phosphorylation of eukaryotic translation initiation factor-2α in Arabidopsis. Journal of Experimental Botany, 59(11), 3131-3141. doi:10.1093/jxb/ern169Lageix, S., Lanet, E., Pouch-Pélissier, M.-N., Espagnol, M.-C., Robaglia, C., Deragon, J.-M., & Pélissier, T. (2008). Arabidopsis eIF2α kinase GCN2 is essential for growth in stress conditions and is activated by wounding. BMC Plant Biology, 8(1), 134. doi:10.1186/1471-2229-8-134Shaikhin, S. M., Smailov, S. K., Lee, A. V., Kozhanov, E. V., & Iskakov, B. K. (1992). Interaction of wheat germ translation initiation factor 2 with GDP and GTP. Biochimie, 74(5), 447-454. doi:10.1016/0300-9084(92)90085-sKrishna, V. M., Janaki, N., & Ramaiah, K. V. A. (1997). Wheat Germ Initiation Factor 2 (WG·eIF2) Decreases the Inhibition in Protein Synthesis and eIF2B Activity of Reticulocyte Lysates Mediated by eIF2α Phosphorylation. Archives of Biochemistry and Biophysics, 346(1), 28-36. doi:10.1006/abbi.1997.0263Immanuel, T. M., Greenwood, D. R., & MacDiarmid, R. M. (2012). A critical review of translation initiation factor eIF2α kinases in plants - regulating protein synthesis during stress. Functional Plant Biology, 39(9), 717. doi:10.1071/fp12116Byrne, E. H., Prosser, I., Muttucumaru, N., Curtis, T. Y., Wingler, A., Powers, S., & Halford, N. G. (2011). Overexpression of GCN2-type protein kinase in wheat has profound effects on free amino acid concentration and gene expression. Plant Biotechnology Journal, 10(3), 328-340. doi:10.1111/j.1467-7652.2011.00665.xDas, M., Reichman, J. R., Haberer, G., Welzl, G., Aceituno, F. F., Mader, M. T., … Olszyk, D. M. (2009). A composite transcriptional signature differentiates responses towards closely related herbicides in Arabidopsis thaliana and Brassica napus. Plant Molecular Biology, 72(4-5), 545-556. doi:10.1007/s11103-009-9590-yYuan, J. S., Tranel, P. J., & Stewart, C. N. (2007). Non-target-site herbicide resistance: a family business. Trends in Plant Science, 12(1), 6-13. doi:10.1016/j.tplants.2006.11.001Peng, Y., Abercrombie, L. L., Yuan, J. S., Riggins, C. W., Sammons, R. D., Tranel, P. J., & Stewart, C. N. (2010). Characterization of the horseweed (Conyza canadensis) transcriptome using GS-FLX 454 pyrosequencing and its application for expression analysis of candidate non-target herbicide resistance genes. Pest Management Science, 66(10), 1053-1062. doi:10.1002/ps.2004Baena-González, E. (2010). Energy Signaling in the Regulation of Gene Expression during Stress. Molecular Plant, 3(2), 300-313. doi:10.1093/mp/ssp113Vivancos, P. D., Driscoll, S. P., Bulman, C. A., Ying, L., Emami, K., Treumann, A., … Foyer, C. H. (2011). Perturbations of Amino Acid Metabolism Associated with Glyphosate-Dependent Inhibition of Shikimic Acid Metabolism Affect Cellular Redox Homeostasis and Alter the Abundance of Proteins Involved in Photosynthesis and Photorespiration. Plant Physiology, 157(1), 256-268. doi:10.1104/pp.111.181024Daudi, A., Cheng, Z., O’Brien, J. A., Mammarella, N., Khan, S., Ausubel, F. M., & Bolwell, G. P. (2012). The Apoplastic Oxidative Burst Peroxidase in Arabidopsis Is a Major Component of Pattern-Triggered Immunity. The Plant Cell, 24(1), 275-287. doi:10.1105/tpc.111.093039Denis, M.-H., & Delrot, S. (1993). Carrier-mediated uptake of glyphosate in broad bean (Vicia faba) via a phosphate transporter. Physiologia Plantarum, 87(4), 569-575. doi:10.1111/j.1399-3054.1993.tb02508.xHetherington, P. R., Marshall, G., Kirkwood, R. C., & Warner, J. M. (1998). Absorption and efflux of glyphosate by cell suspensions. Journal of Experimental Botany, 49(320), 527-533. doi:10.1093/jxb/49.320.527Goossens, A., Dever, T. E., Pascual-Ahuir, A., & Serrano, R. (2001). The Protein Kinase Gcn2p Mediates Sodium Toxicity in Yeast. Journal of Biological Chemistry, 276(33), 30753-30760. doi:10.1074/jbc.m102960200Muaddi, H., Majumder, M., Peidis, P., Papadakis, A. I., Holcik, M., Scheuner, D., … Koromilas, A. E. (2010). Phosphorylation of eIF2α at Serine 51 Is an Important Determinant of Cell Survival and Adaptation to Glucose Deficiency. Molecular Biology of the Cell, 21(18), 3220-3231. doi:10.1091/mbc.e10-01-0023Geiger, D. R., Kapitan, S. W., & Tucci, M. A. (1986). Glyphosate Inhibits Photosynthesis and Allocation of Carbon to Starch in Sugar Beet Leaves. Plant Physiology, 82(2), 468-472. doi:10.1104/pp.82.2.468Cummins, I., Wortley, D. J., Sabbadin, F., He, Z., Coxon, C. R., Straker, H. E., … Edwards, R. (2013). Key role for a glutathione transferase in multiple-herbicide resistance in grass weeds. Proceedings of the National Academy of Sciences, 110(15), 5812-5817. doi:10.1073/pnas.1221179110Orcaray, L., Igal, M., Marino, D., Zabalza, A., & Royuela, M. (2010). The possible role of quinate in the mode of action of glyphosate and acetolactate synthase inhibitors. Pest Management Science, 66(3), 262-269. doi:10.1002/ps.1868Orcaray, L., Zulet, A., Zabalza, A., & Royuela, M. (2012). Impairment of carbon metabolism induced by the herbicide glyphosate. Journal of Plant Physiology, 169(1), 27-33. doi:10.1016/j.jplph.2011.08.009Li, M.-W., AuYeung, W.-K., & Lam, H.-M. (2012). The GCN2 homologue inArabidopsis thalianainteracts with uncharged tRNA and uses Arabidopsis eIF2α molecules as direct substrates. Plant Biology, 15(1), 13-18. doi:10.1111/j.1438-8677.2012.00606.xGe, X., d’ Avignon, D. A., Ackerman, J. J. H., & Sammons, R. D. (2014). In Vivo 31P-Nuclear Magnetic Resonance Studies of Glyphosate Uptake, Vacuolar Sequestration, and Tonoplast Pump Activity in Glyphosate-Resistant Horseweed. PLANT PHYSIOLOGY, 166(3), 1255-1268. doi:10.1104/pp.114.247197Feng, P. C. C., Chiu, T., & Douglas Sammons, R. (2003). Glyphosate efficacy is contributed by its tissue concentration and sensitivity in velvetleaf (Abutilon theophrasti). Pesticide Biochemistry and Physiology, 77(3), 83-91. doi:10.1016/j.pestbp.2003.08.005Koger, C. H., & Reddy, K. N. (2005). Role of absorption and translocation in the mechanism of glyphosate resistance in horseweed (Conyza canadensis). Weed Science, 53(1), 84-89. doi:10.1614/ws-04-102rPerez-Jones, A., Park, K. W., Colquhoun, J., Mallory-Smith, C., & Shaner, D. (2005). Identification of glyphosate-resistant Italian ryegrass (Lolium multiflorum) in Oregon. Weed Science, 53(6), 775-779. doi:10.1614/ws-04-200r.1Morin, F., Vera, V., Nurit, F., Tissut, M., & Marigo, G. (1997). Glyphosate Uptake inCatharanthus roseusCells: Role of a Phosphate Transporter. Pesticide Biochemistry and Physiology, 58(1), 13-22. doi:10.1006/pest.1997.2280Jander, G., Baerson, S. R., Hudak, J. A., Gonzalez, K. A., Gruys, K. J., & Last, R. L. (2003). Ethylmethanesulfonate Saturation Mutagenesis in Arabidopsis to Determine Frequency of Herbicide Resistance. Plant Physiology, 131(1), 139-146. doi:10.1104/pp.102.010397Brotherton, J. E., Jeschke, M. R., Tranel, P. J., & Widholm, J. M. (2007). Identification of Arabidopsis thaliana variants with differential glyphosate responses. Journal of Plant Physiology, 164(10), 1337-1345. doi:10.1016/j.jplph.2006.08.008Forment, J., Gadea, J., Huerta, L., Abizanda, L., Agusti, J., Alamar, S., … Beltran, J. P. (2005). Development of a citrus genome-wide EST collection and cDNA microarray as resources for genomic studies. Plant Molecular Biology, 57(3), 375-391. doi:10.1007/s11103-004-7926-1Medina, I., Carbonell, J., Pulido, L., Madeira, S. C., Goetz, S., Conesa, A., … Dopazo, J. (2010). Babelomics: an integrative platform for the analysis of transcriptomics, proteomics and genomic data with advanced functional profiling. Nucleic Acids Research, 38(suppl_2), W210-W213. doi:10.1093/nar/gkq388Tusher, V. G., Tibshirani, R., & Chu, G. (2001). Significance analysis of microarrays applied to the ionizing radiation response. Proceedings of the National Academy of Sciences, 98(9), 5116-5121. doi:10.1073/pnas.091062498Koger, C. H., Shaner, D. 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Multivalent Calixarene-Based Liposomes as Platforms for Gene and Drug Delivery

The formation of calixarene-based liposomes was investigated, and the characterization of these nanostructures was carried out using several techniques. Four amphiphilic calixarenes were used. The length of the hydrophobic chains attached to the lower rim as well as the nature of the polar group present in the upper rim of the calixarenes were varied. The lipid bilayer was formed with one calixarene and with the phospholipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, DOPE. The cytotoxicity of the liposomes for various cell lines was also studied. From the results obtained, the liposomes formed with the least cytotoxic calixarene, (TEAC12)4 , were used as nanocarriers of both nucleic acids and the antineoplastic drug doxorubicin, DOX. Results showed that (TEAC12)4/DOPE/p-EGFP-C1 lipoplexes, of a given composition, can transfect the genetic material, although the transfection efficiency substantially increases in the presence of an additional amount of DOPE as coadjuvant. On the other hand, the (TEAC12)4/DOPE liposomes present a high doxorubicin encapsulation efficiency, and a slow controlled release, which could diminish the side effects of the drugThis work was financed by the Consejería de Conocimiento, Innovación y Universidades de la Junta de Andalucía (FQM-206, FQM-274, and PY20-01234), the VI Plan Propio Universidad de Sevilla (PP2019/00000748), RTI2018-100692-B-100; P18-RT-1271; PI18-0005-2018; VI-PP AY.SUPLEM2019; RYC-2015-18670, The R+D+I grant PID2019-104195G from the Spanish Ministry of Science and Innovation-Agencia Estatal de Investigación/10.13039/501100011033 (P.H.) and the European Union (Feder Funds). The authors thank the University of Seville for the grant VPPI-US. J.A.L. also thanks the Fundación ONCE funded by the Fondo Social Europe

Major role of nutrient supply in the control of picophytoplankton community structure.

abstractThe Margalef´s mandala (1978) is a simplified bottom-up control model that explains how mixing and nutrient concentration determine the composition of marine phytoplankton communities. Due to the difficulties of measuring turbulence in the field, previous attempts to verify this model have applied different proxies for nutrient supply, and very often used interchangeably the terms mixing and stratification. Moreover, because the mandala was conceived before the discovery of smaller phytoplankton groups (picoplankton <2 μm), it describes only the succession of vegetative phases of microplankton. In order to test the applicability of the classical mandala to picoplankton groups, we used a multidisciplinary approach including specifically designed field observations supported by remote sensing, database analyses, and modeling and laboratory chemostat experiments. Simultaneous estimates of nitrate diffusive fluxes, derived from microturbulence observations, and picoplankton abundance collected in more than 200 stations, spanning widely different hydrographic regimes, showed that the contribution of eukaryotes to picoautotrophic biomass increases with nutrient supply, whereas that of picocyanobacteria shows the opposite trend. These findings were supported by laboratory and modeling chemostat experiments that reproduced the competitive dynamics between picoeukaryote sand picocyanobacteria as a function of changing nutrient supply. Our results indicate that nutrient supply controls the distribution of picoplankton functional groups in the ocean, further supporting the model proposed by Margalef.RADIALES (IEO

Control of tHe structure of marine phytoplAnkton cOmmunities by turbulence and nutrient supply dynamicS (CHAOS)

extended abstract del posterIn order to investigate the role of turbulence mixing on structuring marine phytoplankton communities, the CHAOS project included a multidisciplinary approach involving specifically designed field observations supported by remote sensing, database analyses, and modeling and laboratory chemostat experiments. Field observations carried out in the outer part of Ría de Vigo in summer 2013 showed that, as a result of increased mixing levels, nitrate diffusive input into the euphotic layer was approximately 4-fold higher during spring tides. This nitrate supply could contribute to explain the continuous dominance of large-sized phytoplankton during the upwelling favorable season. Simultaneous estimates of nitrate diffusive fluxes, derived from microturbulence observations, and picoplankton abundance collected in more than 100 stations, spanning widely different hydrographic regimes, showed that the contribution of eukaryotes to picoautotrophic biomass increases with nutrient supply, whereas that of picocyanobacteria shows the opposite trend. These findings were supported by laboratory and modeling chemostat experiments that reproduced the competitive dynamics between picoeukaryote and picocyanobacteria as a function of changing nutrient supply. The results derived from this project confirm that turbulence and mixing control the availability of light and nutrients, which in turn determine the structure of marine phytoplankton communities.RADIALES-20 (IEO), CHAOS (CTM 2012-30680), Malaspina-2010(CSD2008-00077

Delving deeper: metabolic processes in the metalimnion of stratified lakes

Many lakes exhibit seasonal stratification, during which they develop strong thermal and chemical gradients. An expansion of depth-integrated monitoring programs has provided insight into the importance of organic carbon processing that occurs below the upper mixed layer. However, the chemical and physical drivers of metabolism and metabolic coupling remain unresolved, especially in the metalimnion. In this depth zone, sharp gradients in key resources such as light and temperature co-occur with dynamic physical conditions that influence metabolic processes directly and simultaneously hamper the accurate tracing of biological activity. We evaluated the drivers of metalimnetic metabolism and its associated uncertainty across 10 stratified lakes in Europe and North America. We hypothesized that the metalimnion would contribute highly to whole-lake functioning in clear oligotrophic lakes, and that metabolic rates would be highly variable in unstable polymictic lakes. Depth-integrated rates of gross primary production (GPP) and ecosystem respiration (ER) were modelled from diel dissolved oxygen curves using a Bayesian approach. Metabolic estimates were more uncertain below the epilimnion, but uncertainty was not consistently related to lake morphology or mixing regime. Metalimnetic rates exhibited high day-to-day variability in all trophic states, with the metalimnetic contribution to daily whole-lake GPP and ER ranging from 0% to 87% and<1% to 92%, respectively. Nonetheless, the metalimnion of low-nutrient lakes contributed strongly to whole-lake metabolism on average, driven by a col- linear combination of highlight, low surface-water phosphorous concentration and high metalimnetic volume. Consequently, a single-sensor approach does not necessarily reflect whole-ecosystem carbon dynamics in stratified lakes

Nutrient supply does play a role on the structure of marine picophytoplankton communities

Conference communicationThe Margalef´s mandala (1978) is a simplified bottom-up control model that explains how mixing and nutrient concentration determine the composition of marine phytoplankton communities. Due to the difficulties of measuring turbulence in the field, previous attempts to verify this model have applied different proxies for nutrient supply, and very often used interchangeably the terms mixing and stratification. Moreover, because the mandala was conceived before the discovery of smaller phytoplankton groups (picoplankton <2 µm), it describes only the succession of vegetative phases of microplankton. In order to test the applicability of the classical mandala to picoplankton groups, we used a multidisciplinary approach including specifically designed field observations supported by remote sensing, database analyses, and modeling and laboratory chemostat experiments. Simultaneous estimates of nitrate diffusive fluxes, derived from microturbulence observations, and picoplankton abundance collected in more than 200 stations, spanning widely different hydrographic regimes, showed that the contribution of eukaryotes to picoautotrophic biomass increases with nutrient supply, whereas that of picocyanobacteria shows the opposite trend. These findings were supported by laboratory and modeling chemostat experiments that reproduced the competitive dynamics between picoeukaryote sand picocyanobacteria as a function of changing nutrient supply. Our results indicate that nutrient supply controls the distribution of picoplankton functional groups in the ocean, further supporting the model proposed by Margalef.Spanish Governmen