El pie diabético

El pie diabético está considerado como un pie de alto riesgo, está demostrado que si aplicáramos una adecuada y correcta educación sanitaria a todos los profesionales de la salud y al propio paciente, se podrían evitar en la mayoría de los casos las tan temidas amputaciones. En el presente trabajo hacemos referencia de las características más importantes de la diabetes, pie diabético y a la actuación profesional del podólogo frente a estos pacientes.

Comment on “Dynamics of thermal growth of silicon oxide films on Si”

The paper commented on here R. M. C. de Almeida, S. Gonçalves, I. J. R. Baumvol and F. C. Stedile Phys. Rev. B 61 12992 (2000) claims that the Deal and Grove model of oxidation is unable to describe the kinetics in the thin oxide regime due to two main simplifications: (a) the steady-state assumption and (b) the abrupt Si∕SiO2 interface assumption. Although reasonably good fits are obtained without these simplifications, it will be shown that the values of the kinetic parameters are not reliable and that the solutions given for different partial pressures are erroneous. Finally, it will be shown that the correct solution of their model is unable to predict the oxidation rate enhancement observed in the thin oxide regime and that the predicted width of the interface compatible with the Deal and Grove rate constants is too large

Enhancement of oxidation rate of a-Si nanoparticles during dehydrogenation

Oxidation of amorphous silicon (a-Si) nanoparticles grown by plasma-enhanced chemical vapor deposition were investigated. Their hydrogen content has a great influence on the oxidation rate at low temperature. When the mass gain is recorded during a heating ramp in dry air, an oxidation process at low temperature is identified with an onset around 250°C. This temperature onset is similar to that of hydrogen desorption. It is shown that the oxygen uptake during this process almost equals the number of hydrogen atoms present in the nanoparticles. To explain this correlation, we propose that oxidation at low temperature is triggered by the process of hydrogen desorption

Selective ablation of photovoltaic materials with UV laser sources for monolithic interconnection of devices based on a-Si:H

Lasers are essential tools for cell isolation and monolithic interconnection in thin-film-silicon photovoltaic technologies. Laser ablation of transparent conductive oxides (TCOs), amorphous silicon structures and back contact removal are standard processes in industry for monolithic device interconnection. However, material ablation with minimum debris and small heat affected zone is one of the main difficulty is to achieve, to reduce costs and to improve device efficiency. In this paper we present recent results in laser ablation of photovoltaic materials using excimer and UV wavelengths of diode-pumped solid-state (DPSS) laser sources. We discuss results concerning UV ablation of different TCO and thin-film silicon (a-Si:H and nc-Si:H), focussing our study on ablation threshold measurements and process-quality assessment using advanced optical microscopy techniques. In that way we show the advantages of using UV wavelengths for minimizing the characteristic material thermal affection of laser irradiation in the ns regime at higher wavelengths. Additionally we include preliminary results of selective ablation of film on film structures irradiating from the film side (direct writing configuration) including the problem of selective ablation of ZnO films on a-Si:H layers. In that way we demonstrate the potential use of UV wavelengths of fully commercial laser sources as an alternative to standard backscribing process in device fabrication.

30 habitatges a Sant Just Desvern

Descripció del projecte. S’han de destacar les innovacions i aportacions a l’avanç del coneixement que incorpora el projecte. Es poden incorporar memòries, plànols, fotografies, esbossos, etc. També l’adreça web si s’ha penjat més informació sobre el projecte a la web.DESCRIPCIÓ DE L`EDIFICI: L’opció d’edificar fins a la totalitat del perímetre extern del solar, fa buidar el centre i disposar d’un gran pati creuat per passeres, que facilita la ventilació creuada dels habitatges i la il•luminació de banys i cuines. Al voltant d’aquest centre es crea un cinturó de zones humides i l’accés als diferents habitatges. Aquest cinturó d’instal•lacions al voltant del pati central dóna llibertat a les façanes i permet flexibilitat en la tipologia segons el nombre de dormitoris i flexibilitat d’ús en el temps.La traça corba en la confluència de l’Avinguda Indústria i el carrer Ramon i Cajal, fa de la façana una peça autònoma respecte les altres dues façanes posteriors i afavoreix la disposició d’una segona pell (la veritable façana) que es va retranquejant per tal d’aconseguir àmbits per gaudir de l’espai exterior, especialment davant de la zona dels estars.

Disseny de la instal·lació de climatització amb energia geotèrmica i terra radiant d'una vivenda unifamiliar al terme municipal de la Sentiu de Sió

El treball es centra principalment en el disseny de la instal·lació geotèrmica exterior i del terra radiant de l'interior. El disseny es basa en aconseguir el confort de calefacció i s'aprofita el fet de que s'utilitza un sistema reversible per aportar el màxim confort durant l'èpocade refrigeració. Es realitza un estudi de les possibles alternatives per a la instal·lació, també s'observaran els aparells i accessoris escollits per a la implantació de la instal·lació.

Mercado y precios. El Almudí de Lérida, 1700-1833

En el presente trabajo se analiza el origen del almudí de Lérida –mercado de granos de la ciudad, su funcionamiento y su papel en el territorio. En base a la mercurial de Lérida, hemos elaborado una nueva serie de los precios del trigo siguiendo el año agrícola y utilizando cinco mercados, uno por semana. Finalmente, se presenta un primer estudio comparativo para el periodo 1757/58-1807/08 entre estos precios de Lérida y los de Barcelona, elaborados con la misma metodología. Las fuentes principales son los registros de precios y las actas del ayuntamiento de Lérida. Los precios del almudí serán un referente para el conjunto de la Cataluña occidental y el Aragón oriental. A pesar de que el mercado de Lérida está poco regulado, en los momentos de crisis de la segunda mitad del siglo XVIII y en el primer tercio de la siguiente centuria, la municipalidad realiza diversas acciones a favor de los vecinos más necesitados. Estas iniciativas nos remiten a la economía moral. Si bien los nuevos precios de Lérida son, en general, muy similares a los equivalentes realizados con el mercado central del mes, las diferencias son muy significativas para determinados momentos críticos. Este hecho confirma la necesidad de elaborar precios de mayor calidad para los diferentes mercados catalanes y españoles. Finalmente, la comparación de los precios de Lérida y Barcelona del período 1777/78-1807/08 con 1757/58-1776/77, permite confirmar que las coyunturas críticas del último tercio del siglo XVIII y comienzos del siglo XIX provocan respuestas de los diferentes agentes económicos de la Cataluña occidental que retrasan temporalmente la transferencia de la información que reflejan los precios de Barcelona a los precios del almudí de Lérida.

Anàlisi del finançament de l’empresa familiar enfront a la no familiar

Aquest treball presenta un anàlisi comparatiu de l’evolució de l’estructura econòmica i financera que presenten las empreses familiars (EF) i las empreses no familiars (EnF) des de l’any 2007 fins l’any 2011, amb una mostra d’empreses de Catalunya. La comparació d’aquests dos grups es basa amb dades dels estats financers extrets de la base de dades SABI. Aquesta mostra ha permès contrastar les hipòtesis establertes sobre el finançament de les mateixes i concloure que las EF presenten una estructura financera diferent a las EnF. Als seus balanços las EF reflecteixen un major nivell d’autofinançament que las EnF gràcies a la menor distribució de dividends. A més, s’observa que las EF es financen amb un cost de capital aliè inferior al de les EnF. No existeix correlació entre la rendibilitat econòmica i l’endeutament en las EF, és a dir, las EF mantenen un endeutament estable en el temps independentment de la seva rendibilitat, mentre que en el cas de les EnF si que hi ha correlació entre las dos variables, però aquesta és indirecta, de forma que las empreses més endeutades són les menys rentables, posant de manifest major dependència del capital aliè en les EnF que en les EF.

V0 production in p+A collisions at √s = 41.6 GeV

Inclusive doubly differential cross sections d 2 σ pA /dx F   dp T 2 as a function of Feynman-x (x F ) and transverse momentum (p T ) for the production of K S 0 , Λ and Λ¯ in proton-nucleus interactions at 920 GeV are presented. The measurements were performed by HERA-B in the negative x F range (−0.12

Progress in a-Si:H/c-Si heterojunction emitters obtained by Hot-Wire CVD at 200°C

In this work, we investigate heterojunction emitters deposited by Hot-Wire CVD on p-type crystalline silicon. The emitter structure consists of an n-doped film (20 nm) combined with a thin intrinsic hydrogenated amorphous silicon buffer layer (5 nm). The microstructure of these films has been studied by spectroscopic ellipsometry in the UV-visible range. These measurements reveal that the microstructure of the n-doped film is strongly influenced by the amorphous silicon buffer. The Quasy-Steady-State Photoconductance (QSS-PC) technique allows us to estimate implicit open-circuit voltages near 700 mV for heterojunction emitters on p-type (0.8 Ω·cm) FZ silicon wafers. Finally, 1 cm 2 heterojunction solar cells with 15.4% conversion efficiencies (total area) have been fabricated on flat p-type (14 Ω·cm) CZ silicon wafers with aluminum back-surface-field contact.

Current transport and electroluminescence mechanisms in thin SiO2 films containing Si nanocluster-sensitized erbium ions.

We have studied the current transport and electroluminescence properties of metal oxide semiconductor MOS devices in which the oxide layer, which is codoped with silicon nanoclusters and erbium ions, is made by magnetron sputtering. Electrical measurements have allowed us to identify a Poole-Frenkel conduction mechanism. We observe an important contribution of the Si nanoclusters to the conduction in silicon oxide films, and no evidence of Fowler-Nordheim tunneling. The results suggest that the electroluminescence of the erbium ions in these layers is generated by energy transfer from the Si nanoparticles. Finally, we report an electroluminescence power efficiency above 10−3%. © 2009 American Institute of Physics. doi:10.1063/1.3213386

Electrical pump & probe and injected carrier losses quantification in Er doped Si slot waveguides

Electrically driven Er3+ doped Si slot waveguides emitting at 1530 nm are demonstrated. Two different Er3+ doped active layers were fabricated in the slot region: a pure SiO2 and a Si-rich oxide. Pulsed polarization driving of the waveguides was used to characterize the time response of the electroluminescence (EL) and of the signal probe transmission in 1 mm long waveguides. Injected carrier absorption losses modulate the EL signal and, since the carrier lifetime is much smaller than that of Er3+ ions, a sharp EL peak was observed when the polarization was switched off. A time-resolved electrical pump & probe measurement in combination with lock-in amplifier techniques allowed to quantify the injected carrier absorption losses. We found an extinction ratio of 6 dB, passive propagation losses of about 4 dB/mm, and a spectral bandwidth > 25 nm at an effective d.c. power consumption of 120 μW. All these performances suggest the usage of these devices as electro-optical modulators.

Highly textured Sr, Nb, co-doped BiFeO3 thin films grown on SrRuO3/Si substrates by rf-sputtering

In this study, (011)-highly oriented Sr, Nb co-doped BiFeO3 (BFO) thin films were successfully grown on SrRuO3/Si substrates by rf-magnetron sputtering. The presence of parasite magnetic phases was ruled out based on the high resolution x-ray diffraction data. BFO films exhibited a columnar-like grain growth with rms surface roughness values of 5.3 nm and average grain sizes of 65-70 nm for samples with different thicknesses. Remanent polarization values (2Pr) of 54 lC cm 2 at room temperature were found for the BFO films with a ferroelectric behavior characteristic of an asymmetric device structure. Analysis of the leakage mechanisms for this structure in negative bias suggests Schottky injection and a dominant Poole-Frenkel trap-limited conduction at room temperature. Oxygen vacancies and Fe3þ/Fe2þ trap centers are consistent with the surface chemical bonding states analysis from x-ray photoelectron spectroscopy data. The (011)-BFO/ SrRuO3/Si film structure exhibits a strong magnetic interaction at the interface between the multiferroic film and the substrate layer where an enhanced ferromagnetic response at 5 K was observed. Zero-field cooled (ZFC) and field cooled (FC) magnetization curves of this film system revealed a possible spin glass behavior at spin freezing temperatures below 30 K depending on the BFO film thickness.

The valence band alignment at ultrathin SiO2/Si interfaces

High resolution x-ray photoelectron spectroscopy has been used to determine the valence band alignment at ultrathin SiO2/Si interfaces. In the oxide thickness range 1.6-4.4 nm the constant band-offset values of 4.49 and 4.43 eV have been obtained for the dry SiO2/Si(100) and the wet SiO2/Si(100) interfaces, respectively. The valence band alignment of dry SiO2/Si(111) (4.36 eV) is slightly smaller than the case of the dry SiO2/Si(100) interface.