Relatividad especial, relatividad general (1905-1923) : orígenes, desarrollo y recepción por la comunidad científica.

Dentro de un programa más amplio que intenta favorecer los estudios de reflexión, análisis e historia en torno a las Ciencias Físicas, el presente trabajo intenta ser un curso de promoción de profesorado que ofrece una perspectiva histórica y epistemológica de la obra de Einstein, así como las repercusiones que ha tenido. Trabajo teórico de revisión. Fuentes documentales primarias y secundarias. Trabajo teórico de análisis histórico y epistemológico de la obra de Einstein para elaborar material didáctico destinado a cursos de formación. Aspectos tratados: - Marco cultural y científico. Positivismo lógico. Operacionalismo. - Marco teórico de referencia: electrodinámica. - Teoría del electrón. - Teoría de la relatividad: contexto sociocultural en el que surge. Interpretación de la teoría. - Teoría especial. - Conceptos de espacio-tiempo y reinterpretación de la gravedad. - Teoría de la relatividad general. Desarrollos posteriores. Fuentes documentales. Análisis histórico y teórico. El trabajo presenta la teoría de la relatividad en un contexto de producción científica que incluye no sólo la problemática específica de la Física del momento, sino el marco sociológico y los problemas metodológicos y epistemológicos que rodearon su surgimiento. Igualmente se incluyen datos biográficos de Einstein que favorecen la comprensión de su obra. Por último, se destaca la pureza metodológica y el rigor científico de su descubridor.

La nueva reflexión de los hombres de ciencia.

Título anterior de la publicación: Boletín de la Comisión Española de la UNESCO

Talento emprendedor, inteligencia, creatividad y sistema educativo

Se pretende realizar un an??lisis de t??rminos relacionados con el talento, el emprendimiento y la creatividad por entender que estos conceptos deben estar presentes en las sociedades que pretenden seguir creciendo en lo cultural, en lo social y en lo econ??mico. Ya dec??a Einstein que es dif??cil encontrar ni??os que sigan siendo creativos al terminar la escuela. El sistema educativo debe afrontar este reto si quiere ser ??til a la sociedad, favorecer personas cr??ticas y creativas, con pensamientos divergentes, capaces de aprender y desaprender, de reinventarse varias veces a lo largo de su vida.

El Geocamp: un portal informàtic interuniversitari i una eina d'autoedició per les activitats de camp en geologia

GEOCAMP(http://einstein.uab.es/_c_gr_geocamp/geocamp) és una proposta d'innovació educativa desenvolupada per un equip de professors universitaris vinculats a tres universitats catalanes (UdG, UAB i UPC). GEOCAMP és un portal d'Internet que engloba material docent desenvolupat específicament per optimitzar el procés d'aprenentatge en les activitats de camp de Geologia. El GEOCAMP ha estat emprat abastament per estudiants de les universitats en les quals l'equip d'autors imparteix docència. La seva potencialitat i lliure disposició ha permès que el seu ús es generalitzi a d'altres centres i nivells educatius tant a la resta de l'estat com a l'estranger

Temperature and moist-stability effects on midlatitude orographic precipitation

Idealized, convection-resolving simulations of moist orographic flows are conducted to investigate the influence of temperature and moist stability on the drying ratio (DR), defined as the fraction of the impinging water mass removed as orographic precipitation. In flow past a long ridge, where most of the air rises over the barrier rather than detouring around it, DR decreases as the surface temperature (Ts) increases, even as the orographic cap cloud becomes statically unstable at higher Ts and develops embedded convection. This behaviour is explained by a few physical principles: (1) the Clausius–Clapeyron equation dictates that the normalized condensation rate decreases as the flow gets warmer, (2) the replacement of ice-phase precipitation growth with warm-rain processes decreases the efficiency by which condensate is converted to precipitation, thereby lowering precipitation efficiency, and (3) embedded convection acts more to vertically redistribute moisture than to enhance precipitation. Over an isolated mountain, the effects of (1) and (2) are counteracted by moisture deflection around the barrier, which is stronger in the colder, more stable flows.

A review of the theoretical basis for bulk mass flux convective parameterization

Most parameterizations for precipitating convection in use today are bulk schemes, in which an ensemble of cumulus elements with different properties is modelled as a single, representative entraining-detraining plume. We review the underpinning mathematical model for such parameterizations, in particular by comparing it with spectral models in which elements are not combined into the representative plume. The chief merit of a bulk model is that the representative plume can be described by an equation set with the same structure as that which describes each element in a spectral model. The equivalence relies on an ansatz for detrained condensate introduced by Yanai et al. (1973) and on a simplified microphysics. There are also conceptual differences in the closure of bulk and spectral parameterizations. In particular, we show that the convective quasi-equilibrium closure of Arakawa and Schubert (1974) for spectral parameterizations cannot be carried over to a bulk parameterization in a straightforward way. Quasi-equilibrium of the cloud work function assumes a timescale separation between a slow forcing process and a rapid convective response. But, for the natural bulk analogue to the cloud-work function (the dilute CAPE), the relevant forcing is characterised by a different timescale, and so its quasi-equilibrium entails a different physical constraint. Closures of bulk parameterization that use the non-entraining parcel value of CAPE do not suffer from this timescale issue. However, the Yanai et al. (1973) ansatz must be invoked as a necessary ingredient of those closures.

Decoration of au and ag nanoparticles on self-assembling pseudopeptide-based nanofiber by using a short peptide as capping agent for metal nanoparticles

The surface of a nanofiber that is formed from a self-assembling pseudopeptide has been decorated by gold and silver nanoparticles that are stabilized by a dipeptide. Transmission electron microscopic images make the decoration visible. In this paper, a new strategy of mineralizing a pseudopeptide based nanofiber by gold and silver nanoparticles with use of a two-component nanografting method is described.

Formation of triple helical nanofibers using self-assembling chiral benzene-1,3,5-tricarboxamides and reversal of the nanostructure's handedness using mirror image building blocks

Intertwining triple helical nanofibers with an overall handedness have been formed from self-assembling chiral benzene-1,3,5-tricarboxamides 1, 2 and 3, whereas the achiralbenzene-1,3,5-tricarboxamide 4 upon self-association gives rise to straight nanofibers without any twist and transmission electron microscopy images of chiral compounds clearly demonstrate that the handedness of the triple helical nanofibers can be reversed by using the enantiomeric benzene-1,3,5-tricarboxamide building blocks.

Aromatic-aromatic interaction between metallacycle and phenyl ring

The X-ray crystal structure of [CuL2]ClO4 where L is the 1:1 condensate of benzil-monohydrazone and 2-pyridinecarboxalde-hyde, reveals unprecedented pi - pi interaction between the metallacycles and phenyl rings. The interaction is intramolecular. (C) 2003 Elsevier Science B.V. All rights reserved.

A novel copper(I) complex that is a monomeric single helix in solid state but a dimeric double helix in solution

Single helical [(CuL)-L-I]ClO4.12CH(2)Cl(2) (L=1:2 condensate of benzil dihydrazone and 2-acetylpyridine) unfolds and coils up in CH2Cl2 solution to generate double helical [(Cu2L2)-L-I](2+).

The role of protecting groups in the formation of organogels through a nano-fibrillar network formed by self-assembling terminally protected tripeptides

A series of eight synthetic self-assembling terminally blocked tripeptides have been studied for gelation. Some of them form gels in various aromatic solvents including benzene, toluene, xylene, and chlorobenzene. It has been found that the protecting groups play an important role in the formation of organogels. It has been observed that, if the C-terminal has been changed from methyl ester to ethyl ester the gelation property does not change significantly (keeping the N-terminal protecting group same), while the change of the protecting group from ethyl ester to isopropyl ester completely abolishes the gelation property. Similarly, keeping the identical C-terminal protecting group (methyl ester) the results of the gelation study indicate that the substitution of N-terminal protection Boc-(tert-butyloxycarbonyl) to Cbz-(benzyloxycarbonyl) does change the gelation property insignificantly, while the change from Boc- to pivaloyl (Piv-) or acetyl (Ac-) group completely eliminates the gelation property. Morphological studies of the dried gels of two of the peptides indicate the presence of an entangled nano-fibrillar network that might be responsible for gelation. FTIR studies of the gels demonstrate that an intermolecular hydrogen bonding network is formed during gelation. Results of X-ray powder diffraction studies for these gelator peptides in different states (dried gels, gel, and bulk solids) reflected that the structure in the wet gel is distinctly different from the dried gel and solid state structures. Single crystal X-ray diffraction studies of a non-gelator peptide, which is structurally similar to the gelator molecules reveal that the peptide forms an antiparallel beta-sheet structure in crystals. (c) 2007 Elsevier Ltd. All rights reserved.

Imidazole-imidazole stacking in some inorganic complexes

Reaction of CuCl2 center dot 2H(2)O with the 1:1 condensate (L) of 2-(2-aminoethyl) pyridine and 1-methyl-2-imidazolecarboxaldehyde in methanol yields monomeric CuLCl2 center dot H2O (1). Recrystallisation of 1 from aqueous methanol medium containing excess of PF6- affords the 1D coordination polymer [CuLCl](n)(PF6)(n) (2). A chloride bridge results in the coordination polymer. A face-to-face interaction is observed between the imidazole rings in 2. The interaction influences the structure and magnetic properties of 2 markedly. The complex 2 is ferromagnetic with a J value of 1.79 +/- 0.01 cm (1). The imidazole fragments in 2 are coordinated to the metal. In mononuclear [HgL2 ''](ClO4)(2), where L '' is the 1:2 condensate of ethylenediamine and 1-methyl-2-imidazolecarboxaldehyde, the imidazolyl moieties are not under the direct influence of the metal. Here the imidazole-imidazole interaction is angular and more distant. (C) 2009 Elsevier B.V. All rights reserved.