A Random Multifractal Tilling

We develop a multifractal random tilling that fills the square. The multifractal is formed by an arrangement of rectangular blocks of different sizes, areas and number of neighbors. The overall feature of the tilling is an heterogeneous and anisotropic random self-affine object. The multifractal is constructed by an algorithm that makes successive sections of the square. At each $n$-step there is a random choice of a parameter $\rho_i$ related to the section ratio. For the case of random choice between $\rho_1$ and $\rho_2$ we find analytically the full spectrum of fractal dimensions

Mediated Chat 2.0, Embedding Coordination into Chat Tools

Abstract. This research project investigates the coordination of debates using chat tools. In order to evaluate the Mediated Chat 2.0 tool, which implements coordination mechanisms to facilitate the application of group conversation techniques, debates were held during a distance education course using the AulaNet learningware. The logs were analyzed to evaluate how appropriately the proposed mechanisms helped during the coordination of the chat

New Pigeon Pea (\u3cem\u3eCajanus Cajan\u3c/em\u3e) Hybrids With Desirable Forage Traits

Pigeon pea is a tropical forage legume usually sown in mixed pastures with tropical forage grasses. Most of the available cultivars shows erect and tall plants with poor tillering potential, breakable thick stems, low leaf/stem ratios (fresh/dry matter) and low persistence under animal grazing. It shows a high dry matter production, due to low leaf/stem ratios (Barnes & Addo, 1997). Pigeon pea shows good crude protein levels/dry matter (ranging from 14-23%) and regular in vitro digestibility indexes (52-58%) (Karachi & Matata, 1996); animal consumption is affected by high tannin levels of young leaves. Being a self-pollinated species, the variability for forage traits occurs among cultivars available at germplasm banks. No significant variation is observed for any forage character within a given population. Effective selection and releasing of new genetic materials bearing desirable morpho-agronomic and forage traits is mostly dependent on increases of genetic variation, which may be accomplished through artificial crossings between selected parentals. This research work was aimed at the synthesis of new pigeon pea hybrids, hopefully bearing new desirable forage characters

Yield and Quality Parameters of an Interspecific Hybrid \u3cem\u3ePennisetum Purpureum\u3c/em\u3e Schum. (Elephant-Grass) \u3cem\u3eX Pennisetum Glaucum\u3c/em\u3e (L.) R. Br. Stuntz (Pearl Millet)

Elephant-grass is a tropical forage grass used either as a supplement fodder or for direct grazing. It usually shows regular nutritive value (6-13% crude protein, CP, and 55-60% forage digestibility) (Alcantara et al., 1981). Most of the available cultivars produce no viable seeds. On the other hand, pearl millet has high seed yielding potential along with high quality forage (\u3e15% CP and 70% forage digestibility). However, it shows poor forage production, low field persistence under grazing and low regrowth potential after cutting or grazing. During the 90\u27s, an interspecific hybrid between the two species was developed, trying to combine the elephant-grass adaaptability and forage yielding potential with the pearl millet forage quality and seed yielding potential (Schank et al., 1993; Schank, 1996). The new genetic material was able to produce viable seeds in variable amounts (Diz et al., 1995). The main aim of this research was to produce selected populations with high phenotypic uniformities, showing high average forage production and quality

Efeito da adição de catalase no diluidor de sêmen de garanhões da raça Pônei brasileiro.

O objetivo desse estudo foi avaliar por citometria de fluxo o efeito da catalase sobre a integridade da membrana plasmática (IMP) dos espermatozoides durante resfriamento do sêmen de garanhões da raça pônei brasileiro. Foram realizadas coletas de sêmen, semanalmente, de cinco animais, clinicamente sadios e em bom estado nutricional, perfazendo um total de 10 amostras por animal. Após a colheita, o ejaculado foi dividido em duas alíquotas e diluído para uma concentração de 25 milhões de espermatozoides/mL, utilizando o diluidor comercial BotuSÊMEN® (leite desnatado, glicose, conservantes, excipientes e antibióticos segundo o fabricante) aditivado ou não com catalase (200 U/ml). A IMP foi avaliada utilizando-se os fluorocromos iodeto de propídio (IP) e diacetato de carboxifluoresceína (DIC). As subpopulações de espermatozoides foram estabelecidas pela coloração, onde as células coradas com DIC eram os espermatozoides vivos, as coradas com IP os espermatozoides mortos, e as com dupla coloração, os espermatozoides moribundos. A porcentagem de espermatozoides vivos foi significativamente maior quando diluidor foi aditivado com catalase (68,56 ± 10,23 x 80,23 ± 17,38; p < 0,05) Conclui-se que a catalase está correlacionada positivamente com a preservação da integridade da membrana plasmática de espermatozoides de garanhões da raça Pônei Brasileiro

Manejo de solo e água e opções de cultivo em barragem subterrânea.

Este trabalho objetivou a construção do conhecimento sobre manejo do solo e uso da água de barragem subterrânea, bem como avaliar os parâmetros construtivos da tecnologia

Ethylene involvement in the regulation of the H\u3csup\u3e+\u3c/sup\u3e-ATPase \u3ci\u3eCsHA1\u3c/i\u3e gene and of the new isolated ferric reductase \u3ci\u3eCsFRO1\u3c/i\u3e and iron transporter \u3ci\u3eCsIRT1\u3c/i\u3e genes in cucumber plants

In previous works using ethylene inhibitors and precursors, it has been shown that ethylene participates in the regulation of several Fe-deficiency stress responses by Strategy I plants, such as enhanced ferric reductase activity, rhizosphere acidification, and subapical root hair development. Furthermore, recent evidence suggests that ethylene could regulate the expression of both the ferric reductase and the iron transporter genes of Strategy I plants by affecting the FER (or FER-like) transcription factor. Recently, two H+-ATPase genes have been isolated from cucumber roots, CsHA1 and CsHA2. CsHA1 is up-regulated under Fe deficiency while CsHA2 is constitutively expressed. In this work we have cloned and characterized the sequences of the ferric reductase (CsFRO1) and the iron transporter (CsIRT1) genes from cucumber (Cucumis sativus L. cv Ashley). Expression of CsHA1, CsFRO1, and CsIRT1 is diminished in Fe-deficient roots by treatment with ethylene inhibitors, such as Co (cobalt) or AOA (aminooxyacetic acid). Treatment with ethylene precursors, like ACC (1-aminocyclopropane-1-carboxylic acid) or Ethephon (2-chloroethylphosphonic acid), resulted in increased CsHA1, CsFRO1, and CsIRT1 transcript levels and increased ferric reductase activity during early stages of Fe deficiency. These results suggest that ethylene is involved in the regulation of CsHA1, CsFRO1, and CsIRT1 gene expression