Adsorption kinetic investigations of phthalocyanine derivatives self assembled monolayers (SAMs) on gold: Temperature influence on the SAM formation process and quality

The ordered nano-structured surfaces, like self-assembled monolayers (SAMs) are of a great scientific interest, due to the low cost, simplicity, and versatility of this method. SAMs found numerous of applications in molecular electronics, biochemistry and optical devices. Phthalocyanine (Pc) complexes are of particular interest for the SAM preparation. These molecules exhibit fascinating physical properties and are chemically and thermally stable. Moreover their complex structure is advantageous for the fabrication of switchable surfaces. In this work the adsorption process of Pcs derivatives, namely, subphthalocyanines (SubPcB) and terbium (2TbPc) sandwich complexes on gold has been investigated. The influence of the molecular concentration, chain length of peripheral groups, and temperature on the film formation process has been examined using a number of techniques. The SAMs formation process has been followed in situ and in real time by means of second harmonic generation (SHG) and surface plasmon resonance (SPR) spectroscopy. To investigate the quality of the SAMs prepared at different temperatures atomic force microscopy (AFM) and X-Ray photoelectron spectroscopy (XPS)measurements were performed. Valuable information about SubPcB and 2TbPc adsorbtion process has been obtained in the frame of this work. The kinetic data, obtained with SHG and SPR, shows the best conformance with the first order Langmuir kinetic model. Comparing SHG and SPR results, it has been found, that the film formation occurs faster than the formation of chemical bonds. Such, the maximum amount of molecules on the surface is reached after 6 min for SubPcB and 30 min for 2TbPc. However, at this time the amount of formed chemicals bonds is only 10% and 40% for SubPcB and 2TbPc, respectively. The most intriguing result, among others, was obtained at T = 2 °C, where the formation of the less dense SAMs have been detected with SHG.However, analyzing XPS and AFM data, it has been revealed, that there is the same amount of molecules on the surface at both temperature T = 2 °C, and T = 21 °C, but the amount of formed chemicals bond is different. At T = 2 °C molecules form aggregates, therefore many of available anchor groups stay unattached.

A few philosophical ruminations on the human condition and choosing to live well

The notion that life is meaningful through choosing to live well has historically received substantive attention in various philosophical circles, notably the ancient Greek philosophers Socrates, Plato, and Aristotle, and more recently several of the existentialists. In some respects, the idea of choosing to live well is a “thematization” of two widely-recognized, independent components of a meaningful life: happiness and authenticity. I develop this notion of choosing to live well by exploring, developing, and relating these conceptions of happiness and authenticity. By appealing to a very basic account of human nature that has found favor among a great number of people, I show how happiness and authenticity complement each other as conditions for the possibility of living meaningfully.

Making sense of primary science investigations.

EL mensaje de que la ciencia no es sólo un conjunto de conocimientos, sino también una forma de trabajar parece que ha llegado a los profesores, pero todavía no ha calado en los niños. A pesar de los esfuerzos por acercar la Ciencia a los alumnos de primaria, éstos no comprenden del todo bien el proceso o los efectos de la investigación científica. Por este motivo, el objetivo de este texto es ayudar a los docentes a saber transmitir este mensaje a sus alumnos, y lo que es más importante, que éstos sientan muy de cerca la Ciencia.

Sc1 investigation for key stage 1 and key stage 2 : a bank of differentiated investigations for primary schools.

Este documento es un intento de dar orientación y apoyo a los profesores en la organización de la enseñanza de las ciencias de investigación, en el nivel primario. Se presentan distintas actividades, flexibles para los docentes, a fin de que los niños participen en las distintas etapas del proceso de investigación: planificación, obtención y visualización de resultados y, conclusión y evaluación. Así, desarrolla unos conceptos que permitan la progresión en los conocimientos y en las pruebas prácticas de los alumnos, a nivel individual y, para los diferentes niveles educativos. Se incluyen hojas en blanco para ser rellenadas por los alumnos con sus conclusiones de cada uno de los procesos investigados.

Collins new primary maths. Investigations 1 : developing children's investigative and thinking skills in the daily maths lesson.

Para animar a los niños a practicar y consolidar la utilización y aplicación de las matemáticas. Las investigaciones desarrollan la capacidad para resolver problemas, otras habilidades y conceptos para que los niños puedan aplicar sus conocimientos matemáticos a otras áreas del currículo. Contiene aproximadamente sesenta investigaciones, cada una corresponde a un objetivo del currículo renovado que pueden ser integradas en la lección diaria de matemáticas. Ofrece orientación sobre la forma de evaluar el progreso del alumno. Viene con un CD-ROM de modo que el profesor pueda adaptar la investigaciones a las necesidades de su clase.

Collins new primary maths. Investigations 2 : developing children's investigative and thinking skills in the dayly maths lesson.

Para animar a los niños a practicar y consolidar la utilización y aplicación de las matemáticas. Las investigaciones desarrollan la capacidad para resolver problemas, otras habilidades y conceptos para que los niños puedan aplicar sus conocimientos matemáticos a otras áreas del currículo. Contiene aproximadamente sesenta investigaciones, cada una corresponde a un objetivo del currículo renovado que pueden ser integradas en la lección diaria de matemáticas. Ofrece orientación sobre la forma de evaluar el progreso del alumno. Viene con un CD-ROM de modo que el profesor pueda adaptar la investigaciones a las necesidades de su clase.

A orientação homossexual e as investigações acerca da existência de componentes biológicos e genéticos determinantes; The homosexual orientation and investigations about the existence of components biological and genetics determinants

The male and female homosexual orientation has substantial prevalence in humans and can be explained by determinants of various levels: biological, genetic, psychological, social and cultural. However, the biological and genetic evidence have been the main hypotheses tested in scientific research in the world. This article aims to review research studies about the existence of genetic and biological evidence that determine homosexual orientation. Was conducted a review of the literature, using the database MedLine/PubMed and Google scholar. The papers and books were searched in Portuguese and English, using the following keywords: sexual orientation, sexual behavior, homosexuality, developmental Biology and genetics. Was selected papers of the last 22 years. Were found five main theories about the biological components: (1) fraternal birth order, (2) brain androgenization and 2D:4D ratio; (3) brain activation by pheromones; and (4) epigenetic inheritance; and four theories about the genetic components: (1) genetic polymorphism; (2) pattern of X-linked inheritance; (3) monozygotic twins; and (4) sexual antagonistic selection. Concluded that there were many scientific evidence found over time to explain some of biological and genetic components of homosexuality, especially in males. However, today, there is no definitive explanation about what are the determinants of homosexual orientation components.