Thin film evolution equations from (evaporating) dewetting liquid layers to epitaxial growth

In the present contribution we review basic mathematical results for three physical systems involving self-organising solid or liquid films at solid surfaces. The films may undergo a structuring process by dewetting, evaporation/condensation or epitaxial growth, respectively. We highlight similarities and differences of the three systems based on the observation that in certain limits all of them may be described using models of similar form, i.e., time evolution equations for the film thickness profile. Those equations represent gradient dynamics characterized by mobility functions and an underlying energy functional. Two basic steps of mathematical analysis are used to compare the different system. First, we discuss the linear stability of homogeneous steady states, i.e., flat films; and second the systematics of non-trivial steady states, i.e., drop/hole states for dewetting films and quantum dot states in epitaxial growth, respectively. Our aim is to illustrate that the underlying solution structure might be very complex as in the case of epitaxial growth but can be better understood when comparing to the much simpler results for the dewetting liquid film. We furthermore show that the numerical continuation techniques employed can shed some light on this structure in a more convenient way than time-stepping methods. Finally we discuss that the usage of the employed general formulation does not only relate seemingly not related physical systems mathematically, but does as well allow to discuss model extensions in a more unified way

Depinning of three-dimensional drops from wettability defects

Substrate defects crucially influence the onset of sliding drop motion under lateral driving. A finite force is necessary to overcome the pinning influence even of microscale heterogeneities. The depinning dynamics of three-dimensional drops is studied for hydrophilic and hydrophobic wettability defects using a long-wave evolution equation for the film thickness profile. It is found that the nature of the depinning transition explains the experimentally observed stick-slip motion.Comment: 6 pages, 9 figures, submitted to ep

PMO Calculations for the Regiochemistry of 1,3-Cycloadditions of 3,5-Dichloro-2,4,6-trimethylbenzonitrile Oxide to Thiophen, Furan, Benzothiophen, and Benzofuran

A perturbational molecular orbital (PMO) treatment has been developed for the title 1,3-cycloaddition reactions. Molecular orbitals were computed by the CND0/2 method. The results obtained at different levels of approximation of the PMO theory are presented. The regiochemistry is also discussed on the basis of the charge transfer model by using EA\u27s and IP\u27s

Análise da produção de embriões na fertilização in vitro e transferência de embriões para doadoras Nelore.

Ajustou-se uma função de densidade probabilidade para o número de embriões viáveis produzidos após fertilização in vitro em doadoras da raça Nelore, a partir de dados fornecidos pela Associação Brasileira de Criadores de Zebu (ABCZ), referente à análise de 20.619 doadoras, 71.602 aspirações e um total de 509.643 embriões. Modelou-se a densidade probabilidade do número de embriões viáveis mediante a função exponencial, executando-se a determinação dos parâmetros por meio da máxima verossimilhança, em um método de gradiente não linear. O nível de precisão obtido foi de RMSE = 0,040 e R2 = 0,98, para a representação da probabilidade do número de embriões viáveis produzidos por doadoras Nelore na técnica de fertilização in vitro(FIV). Para comparar os modelos (curvas de probabilidade de transferência de embriões ajustada por Beltrame, em 2006, e de FIV, neste trabalho), aplicou-se a técnica de comparação de curvas com o teste F (Silva e Azevedo, 2002). Não foram encontradas diferenças entre as curvas do número de embriões viáveis obtidos após coleta e produzidos após aspiração de doadoras na raça Nelore. Ainda, sugere-se a existência de um fator único limitante que afete biologicamente a produção de embriões nas técnicas de transferência de embriões e fertilização in vitro

Inhibition of Immune Synapse by Altered Dendritic Cell Actin Distribution: A New Pathway of Mesenchymal Stem Cell Immune Regulation

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NF-kB overexpression and decreased immunoexpression of AR in the muscular layer is related to structural damages and apoptosis in cimetidine-treated rat vas deferens

Background: Cimetidine, histamine H-2 receptors antagonist, has caused adverse effects on the male hormones and reproductive tract due to its antiandrogenic effect. in the testes, peritubular myoid cells and muscle vascular cells death has been associated to seminiferous tubules and testicular microvascularization damages, respectively. Either androgen or histamine H-2 receptors have been detected in the mucosa and smooth muscular layer of vas deferens. Thus, the effect of cimetidine on this androgen and histamine-dependent muscular duct was morphologically evaluated.Methods: the animals from cimetidine group (CMTG; n=5) received intraperitoneal injections of 100 mg/kg b.w. of cimetidine for 50 days; the control group (CG) received saline solution. the distal portions of vas deferens were fixed in formaldehyde and embedded in paraffin. Masson's trichrome-stained sections were subjected to morphological and the following morphometrical analyzes: epithelial perimeter and area of the smooth muscular layer. TUNEL (Terminal deoxynucleotidyl-transferase mediated dUTP Nick End Labeling) method, NF-kB (nuclear factor kappa B) and AR (androgen receptors) immunohistochemical detection were also carried out. the birefringent collagen of the muscular layer was quantified in picrosirius red-stained sections under polarized light. the muscular layer was also evaluated under Transmission Electron Microscopy (TEM).Results: in CMTG, the mucosa of vas deferens was intensely folded; the epithelial cells showed numerous pyknotic nuclei and the epithelial perimeter and the area of the muscular layer decreased significantly. Numerous TUNEL-labeled nuclei were found either in the epithelial cells, mainly basal cells, or in the smooth muscle cells which also showed typical features of apoptosis under TEM. While an enhanced NF-kB immunoexpression was found in the cytoplasm of muscle cells, a weak AR immunolabeling was detected in these cells. in CMTG, no significant difference was observed in the birefringent collagen content of the muscular layer in comparison to CG.Conclusions: Cimetidine induces significant damages in the epithelium; a possible antiandrogenic effect on the basal cells turnover should be considered. the cimetidine-induced muscle cells apoptosis confirms the susceptibility of these cells to this drug. the parallelism between enhanced cytoplasmic NF-kB immunolabeling in the damaged muscular tissue and muscle cell apoptosis suggests that this drug may avoid the translocation of NF-kB to the nucleus and interfere in the control of NF-kB-mediated smooth muscle cell apoptosis. the decreased immunoexpression of ARs verified in the damaged muscular tissue reinforces this possibility.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNESP, Araraquara Dent Sch, Lab Histol & Embryol, Dept Morphol, Jaboticabal, Estadual Paulis, BrazilFed Univ São Paulo UNIFESP, Dept Morphol & Genet, São Paulo, BrazilFed Univ São Paulo UNIFESP, Dept Morphol & Genet, São Paulo, BrazilFAPESP: 06/54776-6FAPESP: 08/53288-3FAPESP: 09/17895-5FAPESP: 10/02409-5Web of Scienc

Rentabilidade econômica de cedro-australiano em plantios puros e consorciados com café.

bitstream/item/145005/1/Doc.-284-Edilson.pd

GeoFlow: European Microgravity Experiments on Thermal Convection in Rotating Spherical Shells under influence of Central Force Field

Abstract We report on the status of preparatory work in the GeoFlow Experiment which will take place on board Columbus Orbital Facility (COF) at the International Space Station (ISS). GeoFlow focus on investigations of the stability and dynamics of convective spherical gap flows under influence of a central force field. To exclude the unidirectional gravitational force which acts on earth's surface the planed long-time measurements have to take place in microgravity environment. After a introduction and an overview of experiment hardware preparation status which includes application of measurement techniques, preparatory 3D numerical flow simulations as well as experimental work and the way of experiment data analysis are presented. Also some aspects of the experiment operation phase will be given. The paper is then closed with concluding remarks and an outlook on possible future GeoFlow reflight campaigns

Characterization of the QUartz Photon Intensifying Detector (QUPID) for Noble Liquid Detectors

Dark Matter and Double Beta Decay experiments require extremely low radioactivity within the detector materials. For this purpose, the University of California, Los Angeles and Hamamatsu Photonics have developed the QUartz Photon Intensifying Detector (QUPID), an ultra-low background photodetector based on the Hybrid Avalanche Photo Diode (HAPD) and entirely made of ultraclean synthetic fused silica. In this work we present the basic concept of the QUPID and the testing measurements on QUPIDs from the first production line. Screening of radioactivity at the Gator facility in the Laboratori Nazionali del Gran Sasso has shown that the QUPIDs safely fulfill the low radioactive contamination requirements for the next generation zero background experiments set by Monte Carlo simulations. The quantum efficiency of the QUPID at room temperature is > 30% at the xenon scintillation wavelength. At low temperatures, the QUPID shows a leakage current less than 1 nA and a global gain of 10^5. In these conditions, the photocathode and the anode show > 95% linearity up to 1 uA for the cathode and 3 mA for the anode. The photocathode and collection efficiency are uniform to 80% over the entire surface. In parallel with single photon counting capabilities, the QUPIDs have a good timing response: 1.8 +/- 0.1 ns rise time, 2.5 +/- 0.2 ns fall time, 4.20 +/- 0.05 ns pulse width, and 160 +/- 30 ps transit time spread. The QUPIDs have also been tested in a liquid xenon environment, and scintillation light from 57Co and 210Po radioactive sources were observed.Comment: 15 pages, 22 figure