Microwave-Assisted Formation of Sulfonium Photoacid Generators

We developed a fast, efficient method to prepare commercially important sulfonium salt photoacid generators (PAGs) using microwave-assisted reactions

Fiducia inmobiliaria

El fideicomiso es una figura legal que tiene su origen en el Derecho Romano. Su significado etimológico es el de esperanza cierta y confianza; mientras que en la práctica es tomado como “ fe de encargo “ , mediante el cual una persona transfiere la propiedad de bienes muebles, inmuebles o derechos a una fiduciaria para que ésta los administre de acuerdo a las instrucciones establecidas por el fideicomitente en beneficio de él o de terceros. Existen actualmente proyectos inmobiliarios ya en construcción que pueden dar fe de que el fideicomiso funciona eficientemente, ofreciendo elementos estupendos para atraer la inversión local o extranjera así como fuente generadora de trabajo para amplios sectores de la economía. Estos proyectos atienden demandas en el sector turístico, condominios vacacionales de tiempo compartido en la playa y hoteles; en el sector de la vivienda, complejos urbanísticos en Guayaquil y en Portoviejo; edificios de oficinas, World Trade Center en la Av. Fco. de Orellana en el norte de la ciudad de Guayaquil; Malecón 2000, proyecto que rescata el potencial turístico de nuestra ciudad, entre otros. El éxito de la realización de estos proyectos radica en alcanzar un punto de equilibrio de pre-venta del proyecto, ya que con estos flujos de efectivo el proyecto se viabiliza. Para lograr este cometido son necesarios dos canales de distribución: las Relaciones Públicas y la Venta Directa

Synthesis Of Novel Fluorene-based Two-photon Absorbing Molecules And Their Applications In Optical Data Storage, Microfabricatio

Two-photon absorption (2PA) has been used for a number of scientific and technological applications, exploiting the fact that the 2PA probability is directly proportional to the square of the incident light intensity (while one-photon absorption bears a linear relation to the incident light intensity). This intrinsic property of 2PA leads to 3D spatial localization, important in fields such as optical data storage, fluorescence microscopy, and 3D microfabrication. The spatial confinement that 2PA enables has been used to induce photochemical and photophysical events in increasingly smaller volumes and allowed nonlinear, 2PA-based, technologies to reach sub-diffraction limit resolutions. The primary focus of this dissertation is the development of novel, efficient 2PA, fluorene-based molecules to be used either as photoacid generators (PAGs) or fluorophores. A second aim is to develop more effective methods of synthesizing these compounds. As a third and final objective, the new molecules were used to develop a write-once-read many (WORM) optical data storage system, and stimulated emission depletion probes for bioimaging. In Chapter I, the microwave-assisted synthesis of triarylsulfonium salt photoacid generators (PAGs) from their diphenyliodonium counterparts is reported. The microwave-assisted synthesis of these novel sulfonium salts afforded reaction times 90 to 420 times faster than conventional thermal conditions, with photoacid quantum yields of new sulfonium PAGs ranging from 0.01 to 0.4. These PAGs were used to develop a fluorescence readout-based, nonlinear three-dimensional (3D) optical data storage system (Chapter II). In this system, writing was achieved by acid generation upon two-photon absorption (2PA) of a PAG (at 710 or 730 nm). Readout was then performed by interrogating two-photon absorbing dyes, after protonation, at 860 nm. Two-photon recording and readout of voxels was demonstrated in five and eight consecutive, crosstalk-free layers within a polymer matrix, generating a data storage capacity of up to 1.8 x 1013 bits/cm3. The possibility of using these PAGs in microfabrication is described in Chapter III, where two-photon induced cationic ring-opening polymerization (CROP) crosslinking of an SU8 resin is employed to produce free-standing microstructures. Chapter IV describes the investigation of one- and two-photon stimulated emission transitions by the fluorescence quenching of a sulfonyl-containing fluorene compound in solution at room temperate using a picosecond pump-probe technique. The nature of stimulated transitions under various fluorescence excitation and quenching conditions were analyzed theoretically, and good agreement with experimental data was demonstrated. Two-photon stimulated transitions S1 to S0 were shown at 1064 nm. The two-photon stimulated emission cross section of the sulfonyl fluorophore was estimated as aproximately 240 - 280 GM, making this compound a good candidate for use in two-photon stimulated emission depletion (STED) microscopy

Gestión estratégica de las operadoras de transporte terrestre Intraprovincial de pasajeros en Guayaquil, Ecuador, período del 2013 -2016.

Las operadoras de Transportes Terrestre Intraprovincial de pasajeros, funcionaron agrupados en cooperativas y/o asociaciones, son administradas con dirigencias inexpertas, sobre la base del empirismo por prácticas adquiridas en determinados momentos, con escasos conocimientos educativos y experiencias profesionales. No obstante, estos años se ha acelerado su crecimiento, lo cual hace necesaria una mejor organización que cree procesos en las áreas más críticas, lamentablemente esto no se ha realizado, lo que genera deficiencias que se ha visto reflejada en que actualmente exista un alto porcentaje de clientes insatisfechos. El objetivo de la presente investigación es mejoras en el servicio al Usuario proponiendo un enfoque de gestión estratégica aplicable a las Operadoras de Transporte Terrestre Intraprovincial de pasajeros en Guayaquil. La investigación tuvo un enfoque mixto que implicó la combinación de los métodos tanto cualitativos como cuantitativos. Se acudió a fuentes primarias y a fuentes secundarias. Se identificó la investigación como mixta al emplear como instrumentos para la recolección de los datos, la encuesta y la observación. La elaboración de la propuesta estratégica, permitió revisar y mejorar los procesos internos, lo que le dará mayor eficiencia al sistema de gestión de las operadoras, así como, mejoran los niveles de satisfacción del cliente.The intraprovincial passenger land transport operators, worked as cooperatives and/or associations, they are managed by inexpert leaders based on empiric and developed practices on certain moments with few knowledge and no expertise. However during the years they’ve shown an accelerated growth, which proves that there is a need on finding a better way to organize themselves and also creating processes on critic areas. Unfortunately this hasn’t been done yet, as a result there are a lot of unsatisfied clients. The objective of this investigation is to improve the customer service by proposing a strategic approach applicable to the intraprovincial passenger land transport operators in Guayaquil. The investigation have a mixed approach that includes both methods, qualitative and quantitative. Primary and secondary sources were consulted. The research combine instruments for the collection of data such as survey and observation. The intern processes improved substantially thanks to the strategic proposal, this will allow and give a lot more efficiency to the management system, as a result, better levels of customer service

One- and Two-Photon Stimulated Emission Depletion of a Sulfonyl-Containing Fluorene Derivative

One- and two-photon stimulated emission transitions were investigated by the fluorescence quenching of a sulfonyl-containing fluorene compound, 2,7-bis(4-(phenylsulfonyl)styryl)-9,9-didecyl-9H-fluorene (1), in solution at room temperature using a picosecond pump-probe technique. The nature of stimulated transitions under various fluorescence excitation and quenching conditions was analyzed theoretically, and good agreement with experimental data was demonstrated. Two-photon stimulated transitions S1f S0 were shown for 1 at λq) 1064 nm, representing the first report of two-photon stimulated emission depletion (STED) in a molecular system. The two-photon stimulated emission cross section, δ2PE(λq), of fluorene 1 was estimated to be ∼240-280 GM, suggesting that this compound may be a good candidate for use in two-photon STED microscopy. 1

Visible-Light-Activated Molecular Nanomachines Kill Pancreatic Cancer Cells

Recently, synthetic molecular nanomachines (MNMs) that rotate unidirectionally in response to UV light excitation have been used to produce nanomechanical action on live cells to kill them through the drilling of holes in their cell membranes. In the work here, visible-light-absorbing MNMs are designed and synthesized to enable nanomechanical activation by 405 nm light, thereby using a wavelength of light that is less phototoxic than the previously employed UV wavelengths. Visible-light-absorbing MNMs that kill pancreatic cancer cells upon response to light activation are demonstrated. Evidence is presented to support the conclusion that MNMs do not kill cancer cells by the photothermal effect when used at low optical density. In addition, MNMs suppress the formation of reactive oxygen species, leaving nanomechanical action as the most plausible working mechanism for cell killing under the experimental conditions

Sueño de Escipión

El Sueño de Escipión hace parte de la obra ciceroniana que -se intitulade re publica. Los seis libros de este dialogo, excepto el Sueño que haceparte del último, estuvieron perdidos durante largos siglos, hasta que elCardenal Angelo Mai descubrió en el año de 1820 un palimpsesto en laBiblioteca Vaticana, el cual contiene en la escritura uncial del siglo IV óV más 0 menos, la cuarta parte de la obra, principal mente de los librosI-III .  Además subsisten algunos fragmentos citados por los autores dela antigüedad. El Somnium Scipionis, que ha sido desligado de la totalidad de la obra, probablemente para acompañar el comentario de Macrobio (IV siglo ) , se conserva en muchos manuscritos 2. También gran parte del texto del Sueño es citado por Macrobio en su comentario

Deep Vascular Imaging in Wounds by Two-Photon Fluorescence Microscopy

Deep imaging within tissue (over 300 mu m) at micrometer resolution has become possible with the advent of two-photon fluorescence microscopy (2PFM). The advantages of 2PFM have been used to interrogate endogenous and exogenous fluorophores in the skin. Herein, we employed the integrin (cell-adhesion proteins expressed by invading angiogenic blood vessels) targeting characteristics of a two-photon absorbing fluorescent probe to image new vasculature and fibroblasts up to approximate to 1600 mu m within wound (neodermis)/granulation tissue in lesions made on the skin of mice. Reconstruction revealed three dimensional (3D) architecture of the vascular plexus forming at the regenerating wound tissue and the presence of a fibroblast bed surrounding the capillaries. Biologically crucial events, such as angiogenesis for wound healing, may be illustrated and analyzed in 3D on the whole organ level, providing novel tools for biomedical applications