1,147 research outputs found
Non-Boolean almost perfect nonlinear functions on non-Abelian groups
The purpose of this paper is to present the extended definitions and
characterizations of the classical notions of APN and maximum nonlinear Boolean
functions to deal with the case of mappings from a finite group K to another
one N with the possibility that one or both groups are non-Abelian.Comment: 17 page
Construyendo el significado del cuidado ambiental: un estudio de caso en educación secundaria
Cada vez se hace más evidente que los mayores problemas de nuestro tiempo no pueden comprenderse aisladamente. Los crecientes cambios en el entorno, así como en la sociedad, están llevando a ver la necesidad de tener una transformación de valores, no solo por el bien ecológico, sino por el de la humanidad misma.
En la presente investigación se identifican las concepciones que tienen los alumnos de secundaria acerca del medio ambiente y su deterioro, así como la percepción de los docentes en relación con su desempeño en la formación en valores y actitudes en la educación secundaria, con el fin de contribuir a un cambio de actitudes que fomenten el cuidado del entorno y, por ende, elevar los niveles de la calidad de vida.
Para la recolección de datos se emplearon las redes semánticas naturales y la entrevista semiestructurada, el primer instrumento proporcionó la aproximación hacia la articulación del significado construido por los alumnos en relación con el deterioro ambiental, mientras que la entrevista permitió la evaluación de la perspectiva docente en el abordaje de esta dimensión cognitiva en el proceso educativo
Template-Stripped Multifunctional Wedge and Pyramid Arrays for Magnetic Nanofocusing and Optical Sensing
We present large-scale reproducible
fabrication of multifunctional ultrasharp metallic structures on planar
substrates with capabilities including magnetic field nanofocusing
and plasmonic sensing. Objects with sharp tips such as wedges and
pyramids made with noble metals have been extensively used for enhancing
local electric fields via the lightning-rod effect or plasmonic nanofocusing.
However, analogous nanofocusing of magnetic fields using sharp tips
made with magnetic materials has not been widely realized. Reproducible
fabrication of sharp tips with magnetic as well as noble metal layers
on planar substrates can enable straightforward application of their
material and shape-derived functionalities. We use a template-stripping
method to produce plasmonic-shell-coated nickel wedge and pyramid
arrays at the wafer-scale with tip radius of curvature close to 10
nm. We further explore the magnetic nanofocusing capabilities of these
ultrasharp substrates, deriving analytical formulas and comparing
the results with computer simulations. These structures exhibit nanoscale
spatial control over the trapping of magnetic microbeads and nanoparticles
in solution. Additionally, enhanced optical sensing of analytes by
these plasmonic-shell-coated substrates is demonstrated using surface-enhanced
Raman spectroscopy. These methods can guide the design and fabrication
of novel devices with applications including nanoparticle manipulation,
biosensing, and magnetoplasmonics
S98RS SGB No. 26 (Spring Elections)
A BILL
To appropriate four hundred ninety-five dollars ($495.00) for the creation of fifty (50) double-sided signs in order to promote Spring Elections
The Evolution of Calcium-Based Signalling in Plants
The calcium-based intracellular signalling system is used ubiquitously to couple extracellular stimuli to their characteristic intracellular responses. It is becoming clear from genomic and physiological investigations that while the basic elements in the toolkit are common between plants and animals, evolution has acted in such a way that, in plants, some components have diversified with respect to their animal counterparts, while others have either been lost or have never evolved in the plant lineages. In comparison with animals, in plants there appears to have been a loss of diversity in calcium-influx mechanisms at the plasma membrane. However, the evolution of the calcium-storing vacuole may provide plants with additional possibilities for regulating calcium influx into the cytosol. Among the proteins that are involved in sensing and responding to increases in calcium, plants possess specific decoder proteins that are absent from the animal lineage. In seeking to understand the selection pressures that shaped the plant calcium-signalling toolkit, we consider the evolution of fast electrical signalling. We also note that, in contrast to animals, plants apparently do not make extensive use of cyclic-nucleotide-based signalling. It is possible that reliance on a single intracellular second-messenger-based system, coupled with the requirement to adapt to changing environmental conditions, has helped to define the diversity of components found in the extant plant calcium-signalling toolkit
Rapid cell extraction in aqueous two-phase microdroplet systems
Distinguishing specific cells is an essential technique in cell research and clinical diagnostics. We report a novel method to passively isolate and extract cells in a microfluidic device. We utilise a droplet-based microfluidic system to generate an aqueous two phase system in which aqueous droplets consist of two phases in the form of a double emulsion. Specifically, we generate PEG droplets that completely encapsulate DEX droplets within a microfluidic channel. Target cells can be introduced directly into the droplets and driven to partition to the more favourable phase, whilst still being contained within the aqueous droplet. Human T lymphoma cells, with diameters in the range of 10–15 μm, are chosen as a model cell line to demonstrate the partitioning
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