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29th European Photovoltaic Solar Energy Conference and Exhibition; 112-115, Further development and commercialization of the new generation of optoelectronic and photovoltaic is often limited by the necessity of fabrication of low-cost and efficient transparent conductive electrodes. The development so far is hindered by the conveniently used indium tin oxide (ITO), which suffers from high cost and not high enough availability to support mass production. The zinc oxide is emerging as a convenient replacement for ITO for solar cell and light-emitting diode applications. The optical functions of aluminum-doped zinc oxide thin films are determined using optical spectroscopy measurements from 300 to 1100 nm. The dopant range studied varies from intrinsic ZnO to 5% Al content. Below the direct band gap there is a residual enhancement of the optical absorption coefficient by Al dopants, which is not related to surface roughness. We determined the dielectric functions and absorption coefficient evolution as the dopant concentration increases, as well as the free-carrier concentration.

ZnO films with high conductivity are obtained by atomic layer deposition for application in solar cells based on n CdS/ n CdTe / p Cu₁.₈S heterostructure. The parameters of solar cells with ZnO electrode are calculated from light and dark currentvoltage characteristics and compared with those obtained for structures with Mo contact. The advantages of ZnO electrode are discussed.

Cet article fait suite au 24. Congress of the Polish-Physiological-Society ; Lublin (POL) - (2008-09-11 - 2008-09-13) / Congrès; International audience; Our recent Studies of structure and function of gastrointestinal tract mucosa revealed that the domestification of Sus scrofa corresponds with the significant slowing of the organ development. On top of genetic potential, the nutritional factors (or more precisely - lack of certain biologically active substances in the feed of pregnant sows) arc responsible. Moreover, feeding neonates with milk replacers instead of mother's milk further slows down the development. This is manifested by reduced mitotic activity in the crypts and enhanced apoptosis of enterocytes. The negative effects consist of slower replacement of fetal type, vacuolated enterocytes to adult type enterocytes, modified profile of brush border enzymes, alterations in intestinal mucosa barrier, higher susceptibility to infectious agents, and many others. On the other hand, farmers in order to intensify the production, shorten the suckling period imposing the neonatal piglets to be weaned at 3-4 weeks of life and even earlier. Altogether, it makes the weaning disorders one of the most important problems in pig husbandry, and the mortality of piglets in the leading pig-producing countries still reaches 10%. A number of strategies have been developed to counteract the post-weaning problems. One of them is to stimulate the development of the gastrointestinal tract of the neonate by supplementation of the sow diet with certain biologically active substances and plants. The other idea is to speed up the postnatal development of the gut mucosa for example by plant lectins. Lessons from pig studies can be also useful in human nutrition and medicine since the development of porcine gastrointestinal tract shows a great similarity to that of humans.

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Iron-titanium oxide Fe_1.5Ti_0.5O_3-d obtained by substituting iron by titanium in the hematite structure alpha-Fe_2O_3 is proposed as a "spintronic" material beyond room-temperature: experimental results on bulk and thin films show Fe_2-xTi_xO_3-d to be both magnetic and semiconducting depending on Ti content. Although pure ilmenite FeTiO_3 and pure hematite alpha-Fe_2O_3 are antiferromagnets and insulators, ab-initio calculations predict a half-metallic behaviour for x=0.5. We present here the results obtained for Fe_1.5Ti_0.5O_3-d on epitaxial thin films, grown by pulsed laser deposition technique on c-sapphire at various oxygen pressures (P_O2). The magnetic properties were investigated by SQUID, the electrical properties using classical resistance and Hall effect, and optical absorption using UV-Vis-NIR spectrophotometer. For all oxygen pressures, epitaxial films are single phase. P_O2 appears to be critical parameter for both magnetic and semiconducting properties. High n-type conductivity is obtained at low P_O2 whereas high saturation magnetization M_S and remanence M_R stands for high P_O2 (see fig). Optical absorption data allow associating conduction with the formation of an impurity band.

The use of soybean in human and animal nutrition is limited because of high content of bioactive compounds: enzyme inhibitors, polyphenols, goitrogens, phytates, saponins, sugars, and agglutinins. The damage of intestinal mucosa structure was previously observed in animals fed soybean supplemented diets. Hence, the objectives of the presented study were to compare intensity of epithelium remodeling processes in different intestinal segments, and to evaluate the influence of the 1% of soybean dietary supplementation on the processes in intestinal mucosa. The experiment was performed on 30 Wistar rats fed AIN-93 based diets. Animals were divided randomly into three groups: control (CTRL), with 1% of raw soybean (RS) and with 1% of soaked and boiled soybean (BS). The samples of: duodenum (DUO), proximal jejunum (PROX), mid-jejunum (MID), distal-jejunum (DIST) and ileum (ILE) were collected. The following processes in these samples were evaluated: mitosis (Ki-67), apoptosis (Cpp32), autophagy (MAP I LC3) and DNA damage (p53). Present data show that modification of soybean by soaking and subsequent boiling markedly influences the enterocyte turnover in the small intestine mucosa. Increased mitotic ratio in the intestine of rats fed with boiled soybean masks the negative effects of soybean on the small intestine structure.

Effects of n-type doping of GaN epilayers and InGaN/GaN quantum well structures are studied. We evaluate the influence of n-type doping on a structural quality of the samples (using atomic force and scanning electron microscopy), on light emission intensity and on in-plane emission intensity variations. Possible mechanisms responsible for strong enhancement of light emission from doped samples are discussed. © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.