939 research outputs found
BiGlobal and point vortex methods for the instability analysis of wakes
To better understand destruction mechanisms of wake-vortices behind aircraft, the point vortex method for stability (inviscid) used by Crow is here compared with viscous modal global stability analysis of the linearized Navier-Stokes equations acting on a two-dimensional basic flow, i.e. BiGlobal stability analysis.
The fact that the BiGlobal method is viscous, and uses a flnite área vortex model, gives rise to results somewhat different from the point vortex model. It adds more parameters to the problem, but is more realistic
Una política cultural autónoma.
A partir de la segunda guerra mundial toda el área latinoamericana, y ya no un sector de su zona Norte que conocía el fenómeno desde fines del siglo XIX, ha venido presenciando la agudización de la influencia cultural norteamericana como un aspecto derivado y a la vez complementario, de su expansionismo económico, político y militar, que encontraba en la región latinoamericana inmediatamente vecina elementos propicios a su intervención
Intracellular Zn2+ detection with quantum dot-based FLIM nanosensors
Fluorescence Lifetime Imaging Microscopy (FLIM) has been
employed for the detection of intracellular Zn2+ levels, implicated
in various signalling pathways, using a family of quantum dot (QD)
nanosensors. The sensing mechanism was based on photoinduced
electron transfer (PET) between an azacycle receptor group and the
QD nanoparticles.This work was supported by Fundación Ramon Areces and grant CTQ2014-56370-R from Ministerio de Economia y Competitividad of Spain
Circularly Polarized Luminescence of [6]Helicenes through Excited-State Intramolecular Proton Transfer
We present the concept of combining circularly polarized luminescence (CPL) and excited-state intramolecular proton transfer (ESIPT) features into a single molecule as a strategy to generate high-performance ESIPT-based CPL materials. For this purpose, a [6]helicene bearing two ESIPT structural units was synthesized using a double Suzuki–Miyaura reaction and a double C(sp2)−H hydroxylation approach. The photophysical properties of the doubly hydroxylated [6]helicene were studied in parallel with a non-hydroxylated [6]helicene control compound, revealing that the presence of a chiral [6]helicene unit results in a strong CPL response and the presence of the ESIPT units in a considerable red shift. The red-shifted emission along with the outstanding glum (≈10−2) and a large Stokes shift makes the doubly hydroxylated [6]helicene a promising candidate for use in optoelectronics
Metallofluorescent Nanoparticles for Multimodal Applications
Herein, we describe
the synthesis and application of cross-linked
polystyrene-based dual-function nano- and microparticles containing
both fluorescent tags and metals. Despite containing a single dye,
these particles exhibit a characteristic dual-band fluorescence emission.
Moreover, these particles can be combined with different metal ions
to obtain hybrid metallofluorescent particles. We demonstrate that
these particles are easily nanofected into living cells, allowing
them to be used for effective fingerprinting in multimodal fluorescence-based
and mass spectrometry-based flow cytometry experiments. Likewise,
the in situ reductions of the metal ions enable other potential uses
of the particles as heterogeneous catalysts
Novel ortho-OPE metallofoldamers: binding-induced folding promoted by nucleating Ag(i)-alkyne interactions
We have developed a new family of ortho-oligophenylene ethynylene (o-OPE) metallofoldamers. The folding of these helicates is induced by nucleating carbon-metal interactions between Ag(i) cations and the alkynes of the inner core of the o-OPEs. These o-OPEs form metal-organic assemblies where at least three alkyne moieties are held in close proximity to form novel Ag(i)-complexes with the metal ion lodged into the helical cavity. NMR titration experiments and photokinetic studies have provided quantitative data about the thermodynamic and kinetic features of such binding/folding phenomena. X-ray diffraction and DFT studies have been performed to extract structural information on how the Ag(i) cation is accommodated into the cavity. The great simplicity and versatility of these new metallofoldamers open up the possibility to develop novel structures with applications in material science and/or in asymmetric catalysisThis research was funded by the Regional Government of Andalucía (project P09-FQM-4571) and the ICIQ Foundation. DM thanks Regional Government of Andalucía for her contract. AML thanks MICINN for her FPU fellowship. The authors thank the Centro de Servicios de Informática y Redes de Comunicaciones (CSIRC), Universidad de Granada, for providing the computing tim
Variables sociodemográficas y niveles de educación financiera en jóvenes universitarios de Ecuador
Socio-demographic variables and levels of financial education among young university students in EcuadorThis study investigates the relationship between sociodemographic variables and the level of fin ancial education among university students in Ecuador. Using data from 1,011 surveys and non-parametric analysis, it examines how age, gender, employment status, and field of study relate to students' financial knowledge, behavior, and attitudes. The results reveal that the majority of students in Ecuador possess a moderate level of financial education, signifying their ability to apply basic financial concepts in everyday situations but with limitations in more complex scenarios. Additionally, it was found that age, field of study, and employment status significantly influence the dimensions of financial education. This pioneering study in the Ecuadorian context underscores the importance of considering sociodemographic factors when designing financial education strategies tailored to university students, with the aim of strengthening the financial education of this population. Este estudio investiga la relación entre variables sociodemográficas y el nivel de educación financiera en jóvenes universitarios de Ecuador. Utilizando datos de 1.011 encuestas y el contraste no paramétrico, se analiza cómo la edad, el género, el estatus laboral y el campo de formación se relacionan con el conocimiento, comportamiento y la actitud financiera de los estudiantes universitarios. Los resultados revelan que la mayoría de los estudiantes en Ecuador poseen un nivel medio de educación financiera, lo que implica habilidades para aplicar conceptos financieros básicos en situaciones cotidianas, pero con limitaciones en escenarios más complejos. Además, se encontró que la edad, el campo de formación y el estatus laboral influyen significativamente en las dimensiones de la educación financiera. Este estudio pionero en el contexto ecuatoriano subraya la importancia de considerar factores sociodemográficos al diseñar estrategias de educación financiera dirigidas a jóvenes universitarios, con el objetivo de fortalecer la educación financiera de esta población
Biological activities of fluorescent Trypanosome Alternative Oxidase inhibitor conjugates incorporating a cationic julolidine-based viscosity sensor
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