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Artigo Revisado por pares

Theodore W. Schultz,

... Casado-Lumbreras, Ricardo Colomo-Palacios, Adrián Hernández-López, Pedro Soto-Acosta Personnel Performance Appraisal Coverage in ITIL, COBIT ... Casado-Lumbreras, Ricardo Colomo-Palacios, Adrián Hernández-López, Pedro Soto-Acosta Personnel Performance Appraisal Coverage in ITIL, COBIT ... Casado-Lumbreras, Ricardo Colomo-Palacios, Adrián Hernández-López, Pedro Soto-Acosta Personnel Performance Appraisal Coverage in ITIL, COBIT, ...

Tópico(s): Gender Diversity and Inequality

1959 - University of Chicago Press | Social Service Review

Artigo Revisado por pares

Ricardo Colomo‐Palacios, Cristina Casado‐Lumbreras, Pedro Soto‐Acosta, Sanjay Misra, Francisco José García‐Peñalvo,

... development, staffing and, lately, emotions in organizational contexts.Pedro Soto-AcostaPedro Soto-Acosta is an associate professor of ...

Tópico(s): Knowledge Management and Sharing

2012 - Taylor & Francis | Journal of Global Information Technology Management

Primary Document Acesso aberto

Shipp, Barnard,

Includes bibliographical references. v. 1. Hernando de Soto and Florida. ... de Gourgue to Florida. 1567. Escalante Fontaneda, H. d'. The country and ...

0000 - Gale Group | Sabin

Artigo Revisado por pares

Elena Aznar, Carmen Coll, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós, Joan Cano, Eliseo Ruíz,

Abstract We report the development of an MCM‐41 mesoporous support that is functionalised with saccharides at the pore outlets and contains the dye [Ru(bipy) 3 ] 2+ in the pores (solid S1 ; bipy=2,2′‐bipyridyl). For this hybrid system, the inhibition of mass transport of the dye from the pore voids to the bulk solution in the presence of borate is demonstrated in water at neutral pH. The formation of the corresponding boroester derivative is related to the selective reaction of borate with the appended ...

Tópico(s): Mesoporous Materials and Catalysis

2009 - Wiley | Chemistry - A European Journal

Primary Document Acesso aberto

Shipp, Barnard,

Includes bibliographical references. v. 1. Hernando de Soto and Florida. ... de Gourgue to Florida. 1567. Escalante Fontaneda, H. d'. The country and ...

0000 - Gale Group | Sabin

Artigo Acesso aberto Revisado por pares

Juan Antonio López, F. Soto, Pedro Sánchez, Andrés Iborra, Juan Suardíaz Muro, Juan A. Vera,

This paper presents the design of a new wireless sensor node (GAIA Soil-Mote) for precision horticulture applications which permits the use of precision agricultural instruments based on the SDI-12 standard. Wireless communication is achieved with a transceiver compliant with the IEEE 802.15.4 standard. The GAIA Soil-Mote software implementation is based on TinyOS. A two-phase methodology was devised to validate the design of this sensor node. The first phase consisted of laboratory validation of ...

Tópico(s): Water Quality Monitoring Technologies

2009 - Multidisciplinary Digital Publishing Institute | Sensors

Primary Document Acesso aberto

Shipp, Barnard,

Includes bibliographical references. v. 1. Hernando de Soto and Florida. ... de Gourgue to Florida. 1567. Escalante Fontaneda, H. d'. The country and ...

0000 - Gale Group | Sabin

Artigo Revisado por pares

Estela Climent, Andrea Bernardos, Ramón Martínez‐Máñez, Ángel Maquieira, M. Dolores Marcos, Nuria Pastor-Navarro, Rosa Puchades, Félix Sancenón, Juán Soto, Pedro Amorós,

This paper describes the design of new controlled delivery systems consisting of a mesoporous support functionalized on the pore outlets with a certain hapten able to interact with an antibody that acts as a nanoscopic cap. The opening protocol and delivery of the entrapped guest is related by a displacement reaction involving the presence in the solution of the antigen to which the antibody is selective. As a proof-of-the-concept, the solid MCM-41 was selected as support and was loaded with the ...

Tópico(s): Porphyrin and Phthalocyanine Chemistry

2009 - American Chemical Society | Journal of the American Chemical Society

Artigo Revisado por pares

Gabriel Jaramillo‐Soto, Pedro R. García‐Morán, Francisco Javier Enríquez‐Medrano, Hortensia Maldonado‐Textle, Martha Albores‐Velasco, Ramiro Guerrero‐Santos, Eduardo Vivaldo‐Lima,

An experimental study on the reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in supercritical carbon dioxide is presented. A 38 mL, high-pressure view cell with two frontal and two lateral sapphire windows was used as reactor. Poly(styrene-block-dimethylsiloxane) was used as stabilizer. The performance as RAFT controllers of S-thiobenzoyl thioglycolic acid, methyl naphthalene dithiobenzoate, 4-methyl allyl dithiobenzoate, and benzyl-N,N-dimethyldithiocarbamate was ...

Tópico(s): Carbon dioxide utilization in catalysis

2009 - Elsevier BV | Polymer

Artigo Revisado por pares

Jorge J. Hernández‐Meza, Gabriel Jaramillo‐Soto, Pedro R. García‐Morán, Joaquín Palacios‐Alquisira, Eduardo Vivaldo‐Lima,

Abstract Calculations of the polymerization rate and molecular weight development in the nitroxide‐mediated radical polymerization (NMRP) of styrene (STY), using hydroxyl‐TEMPO and dibenzoyl peroxide (BPO), and activated by microwave irradiation (MI), are presented. The calculations are based on a kinetic model developed in our group. Microwave activation is modeled by three approaches: microwave‐activated production of free radicals from monomer molecules, microwave‐enhanced thermal initiation, and ...

Tópico(s): Photopolymerization techniques and applications

2009 - Wiley | Macromolecular Reaction Engineering

Artigo Revisado por pares

Elena Aznar, Ma Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós, Carmen Guillem,

This paper proposes a new nanoscopic molecular movable gate-like functional hybrid system consisting of nanoscopic MCM-41-based material functionalized onto pore outlets with a saccharide derivative capable of interacting with boronic acid functionalized gold nanoparticles (AuNPs) acting as nanoscopic caps. The gating mechanism involves the reversible reaction between polyalcohols and boronic acids to form boronate esters. Functionalized AuNPs thus act as a suitable nanoscopic cap via the reversible ...

Tópico(s): Porphyrin and Phthalocyanine Chemistry

2009 - American Chemical Society | Journal of the American Chemical Society

Artigo Revisado por pares

José V. Ros‐Lis, Rosa Casasús, María Comes, Carmen Coll, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós, Jamal El Haskouri, N. Garro, Knut Rurack,

Dual-function hybrid material U1 was designed for simultaneous chromofluorogenic detection and removal of Hg(2+) in an aqueous environment. Mesoporous material UVM-7 (MCM41 type) with homogeneously distributed pores of about 2-3 nm in size, a large specific surface area exceeding 1000 m(2) g(-1), and nanoscale particles was used as an inorganic support. The mesoporous solid is decorated with thiol groups that were treated with squaraine dye III to give a 2,4-bis(4-dialkylaminophenyl)-3-hydroxy-4- ...

Tópico(s): Gas Sensing Nanomaterials and Sensors

2008 - Wiley | Chemistry - A European Journal

Artigo Revisado por pares

Rosa Casasús, Estela Climent, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós, Joan Cano, Eliseo Ruíz,

The development of gate-like systems able to perform certain programmed functions is an interesting way of taking chemistry to the frontiers of nanoscience. In relation to this field, we report a complete study of the behavior of a pH-driven and anion-controlled nano-supramolecular gate-like ensemble obtained by anchoring suitable polyamines on the pore outlets of mesoporous materials of the type MCM-41 (solid N3-S). The release of an entrapped dye (Ru(bipy)32+) from the pore voids into the bulk solution ...

Tópico(s): Supramolecular Chemistry and Complexes

2008 - American Chemical Society | Journal of the American Chemical Society

Artigo Revisado por pares

Carmen Coll, Elena Aznar, Ramón Martínez‐Máñez, M. Dolores Marcos, Félix Sancenón, Juán Soto, Pedro Amorós, Joan Cano, Eliseo Ruíz,

We report the preparation of a MCM-41 mesoporous material that contains the dye [Ru(bipy)(3)]Cl(2) (bipy=bipyridine) inside the mesopores and functionalised with suitable binding groups at the entrance of the pores. Solids S1-S3 were obtained by the reaction of the mesoporous material with N-methyl-N'-propyltrimethoxysilylimidazolium chloride, N-phenyl-N'-[3-(trimethoxysilyl)propyl]thiourea, or N-phenyl-N'-[3-(trimethoxysilyl)propyl]urea, respectively. A study of the dye delivery of these systems ...

Tópico(s): Porphyrin and Phthalocyanine Chemistry

2010 - Wiley | Chemistry - A European Journal

Artigo Revisado por pares

Víctor Contreras, Oracio Barbosa-Garcı́a, J. L. Pichardo-Molina, Gabriel Ramos‐Ortíz, José‐Luis Maldonado, M.A. Meneses-Nava, Nancy Ornelas‐Soto, Pedro Luı́s López-de-Alba,

Based on UV–VIS spectroscopy and chemometric techniques, a screening method is presented with which the studied brands of white and rested tequila can be differentiated among them and on the other hand, adulterate and fake tequilas can be distinguished from the corresponding genuine brands. Eighty bottles of tequila (39 white type and 41 rested type) were studied and purchased at liquor stores; special care was taken to get different batches. Through the use of support vector machine (SVM), principal ...

Tópico(s): Advanced Chemical Sensor Technologies

2010 - Elsevier BV | Food Research International

Artigo Revisado por pares

Ignacio de Godos, Virginia A. Vargas, Saúl Blanco, María Cruz García-González, Roberto Soto, Pedro A. García‐Encina, Eloy Bécares, Raúl Muñoz,

Two green microalgae (Scenedesmus obliquus and Chlorella sorokiniana), one cyanobacterium (Spirulina platensis), one euglenophyt (Euglena viridis) and two microalgae consortia were evaluated for their ability to support carbon, nitrogen and phosphorous removal in symbiosis with activated sludge bacteria during the biodegradation of four and eight times diluted piggery wastewater in batch tests. C. sorokiniana and E. viridis were capable of supporting the biodegradation of four and eight times diluted ...

Tópico(s): Aquatic Ecosystems and Phytoplankton Dynamics

2010 - Elsevier BV | Bioresource Technology

Artigo Revisado por pares

Ignacio de Godos, Héctor Guzmán, Roberto Soto, Pedro A. García‐Encina, Eloy Bécares, Raúl Muñoz, Virginia A. Vargas,

Two conventional chemical coagulants (FeCl3 and Fe2(SO4)3) and five commercial polymeric flocculants (Drewfloc 447, Flocudex CS/5000, Flocusol CM/78, Chemifloc CV/300 and Chitosan) were comparatively evaluated for their ability to remove algal–bacterial biomass from the effluent of a photosynthetically oxygenated piggery wastewater biodegradation process. Chlorella sorokiniana, Scenedesmus obliquus, Chlorococcum sp. and a wild type Chlorella, in symbiosis with a bacterial consortium, were used as ...

Tópico(s): Constructed Wetlands for Wastewater Treatment

2010 - Elsevier BV | Bioresource Technology

Artigo Acesso aberto Revisado por pares

Carmen Coll, Rosa Casasús, Elena Aznar, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós,

Hybrid mesoporous systems containing a gate-like ensemble functionalised with imidazolium groups and a dye are used for the selective colorimetric sensing of long-chain carboxylates.

Tópico(s): Luminescence and Fluorescent Materials

2007 - Royal Society of Chemistry | Chemical Communications

Artigo Acesso aberto Revisado por pares

Elena Aznar, Rosa Casasús, Beatriz García-Acosta, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós,

A two-channel switchable nanoscopic hybrid system, able to modulate mass transport by photoresponsive appended organic groups and the presence of G1.5 PAMAM dendrimers as molecular caps, is reported. This new functional gatelike ensemble is chemically (by pH changes) and photochemically (using visible light) controlled in pure aqueous solution, as demonstrated by an experiment involving the controlled release of a dye (see figure).

Tópico(s): Dendrimers and Hyperbranched Polymers

2007 - | Advanced Materials

Artigo Revisado por pares

María Isabel Rodríguez‐Cáceres, Isabel Durán‐Merás, Nancy Ornelas‐Soto, Pedro Luís López de Alba, L. López-Martínez,

In this work four spectrofluorimetric methods for the determination of irinotecan (CPT-11) in human urine and pharmaceuticals have been developed. Initially, the fluorescent characteristics of irinotecan (CPT-11) have been studied in both acidic and basic media. Later, the fluorescence emission generated by the oxidation of CPT-11 with several agents was studied. A quenching of fluorescence could be observed in the presence of Ce(IV) and I2/I−. Also, the reaction between several divalent and trivalent ...

Tópico(s): Antibiotics Pharmacokinetics and Efficacy

2007 - Elsevier BV | Talanta

Artigo Revisado por pares

Carmen Coll, Laura Mondragón, Ramón Martínez‐Máñez, Félix Sancenón, M. Dolores Marcos, Juán Soto, Pedro Amorós, Enríque Pérez‐Payá,

Gut behütet: Peptide, die auf der Oberfläche von mesoporösen Silicat-Trägern verankert wurden, fungieren als „Torwache“. Auf diese Weise werden absolut dichte Transportmaterialien erhalten, die die Ladung erst in Gegenwart einer passenden Peptidase selektiv freisetzen (siehe Bild, rote Kreise: Ladung, bunte Ketten: Peptide).

Tópico(s): Molecular Junctions and Nanostructures

2011 - Wiley | Angewandte Chemie

Artigo Revisado por pares

Carmen Coll, Laura Mondragón, Ramón Martínez‐Máñez, Félix Sancenón, M. Dolores Marcos, Juán Soto, Pedro Amorós, Enríque Pérez‐Payá,

Gated community: Peptides anchored to the surface of silica mesoporous supports by a valid procedure act as gatekeepers. In this way, "zero release" supports that selectively deliver the cargo in the presence of a suitable peptidase are obtained (see picture, red spheres: cargo, colored chains: peptides).

Tópico(s): Advanced biosensing and bioanalysis techniques

2011 - Wiley | Angewandte Chemie International Edition

Artigo Acesso aberto Revisado por pares

Bernd Zolitschka, Frank Schäbitz, Andreas Lücke, Hugo Corbella, Bettina Ercolano, Michael Fey, Torsten Haberzettl, Stephanie Janssen, Nora I. Maidana, Christoph Mayr, Christian Ohlendorf, Gabriel Oliva, Marta M. Paez, Gerhard H. Schleser, Julio Soto, Pedro Tiberi, Michael Wille,

Sedimentary records from crater lakes are of major scientific interest because they provide continuous high-resolution climatic and environmental archives. From a limnogeological survey of crater lakes performed in the Pali Aike Volcanic Field (52°S, southeastern Patagonia, Santa Cruz, Argentina), two deep crater lakes have been recognized: Laguna Potrok Aike (100 m water depth) and Laguna Azul (56 m water depth). Physico-chemical analyses of these closed lake systems demonstrate that Laguna Azul has ...

Tópico(s): Groundwater and Isotope Geochemistry

2006 - Elsevier BV | Journal of South American Earth Sciences

Artigo Revisado por pares

Rosa Casasús, Elena Aznar, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós,

Colorimetric guest signaling is effected by a supramolecular approach that uses a mesoporous hybrid solid functionalized with gatelike scaffoldings. When the gate is open, a dye (see scheme; orange dots) embedded in the pore walls of a mesoporous solid is released into the solution giving color. If the appropriate anion (red dots) is present the gate is closed, the dye is locked into the pores, and the solution remains colorless. Supporting information for this article is available on the WWW under ...

Tópico(s): Luminescence and Fluorescent Materials

2006 - Wiley | Angewandte Chemie International Edition

Artigo Revisado por pares

Rosa Casasús, Elena Aznar, M. Dolores Marcos, Ramón Martínez‐Máñez, Félix Sancenón, Juán Soto, Pedro Amorós,

Farbe bekennen: Ein supramolekularer Ansatz, basierend auf einem mesoporösen hybriden Feststoff mit torartigen Bauelementen, ermöglicht die kolorimetrische Signalgebung eines Gastmoleküls. Ein in die Porenwände des Feststoffs eingebetteter Farbstoff wird bei offenem Tor in die Lösung abgegeben und färbt diese. Ist ein geeignetes Anion vorhanden, öffnet sich das Tor nicht, und der Farbstoff ist in den Poren eingeschlossen – die Lösung bleibt farblos (siehe Schema).

Tópico(s): Supramolecular Self-Assembly in Materials

2006 - Wiley | Angewandte Chemie

Artigo Acesso aberto Revisado por pares

Eulogio H. Soto, Pedro Báez, María Eliana Ramírez, Sergio Letelier, Javier Naretto, Andrea Rebolledo,

Through an oceanographic cruise carried out between the southern area of Aysén and the northern one of Magallanes, Canal Trinidad to Canal Smyth (50º00'S, 75º00'W to 52º00'S, 73º48'W), 13 collecting stations were made to gather biological material to record and characterizing the intertidal biotopes of this extended area.A total of 19 biotopes were identified, from which 12 of those had been recorded previously at more septentrional areas of Aysén; other 6 represented variations of those previously ...

Tópico(s): Cephalopods and Marine Biology

2012 - University of Valparaíso | Revista de biología marina y oceanografía

Artigo Revisado por pares

Alessandro Agostini, Félix Sancenón, Ramón Martínez‐Máñez, M. Dolores Marcos, Juán Soto, Pedro Amorós,

Light-controlled gate: A novel capped silica nanoscopic mesoporous hybrid material for photo-driven cargo release applications has been designed and prepared. The capped system, which shows a zero release, contains a photo-cleavable bulky o-methoxybenzylamine derivative. Upon irradiation at 254 nm, photo-degradation of the o-methoxybenzylamine framework and the subsequent delivery of a fluorescent cargo were observed (see figure). Detailed facts of importance to specialist readers are published as " ...

Tópico(s): Analytical Chemistry and Sensors

2012 - Wiley | Chemistry - A European Journal

Artigo Acesso aberto Revisado por pares

Estela Climent, Ramón Martínez‐Máñez, Ángel Maquieira, Félix Sancenón, M. Dolores Marcos, Eva M. Brun, Juán Soto, Pedro Amorós,

Abstract The synthesis of capped mesoporous silica nanoparticles (MSN) conjugated with an antibody (AB) as a gatekeeper has been carried out in order to obtain a delivery system able to release an entrapped cargo (dye) in the presence of a target molecule (antigen) to which the conjugated antibody binds selectively. In particular, MSN loaded with rhodamine B and functionalized on the external surface with a suitable derivative of N ‐( t ‐butyl)‐3‐oxo‐(5α,17β)‐4‐aza‐androst‐1‐ene‐17‐carboxamide (finasteride) ...

Tópico(s): Analytical Chemistry and Chromatography

2012 - WileyOpen | ChemistryOpen