Non-conventional formulations for the finite element method

de Freitas, J.A. Teixeira,de Almeida, J.P. Moitinho,Peraira, E.M.B. Ribeiro Techno-Press 1996 Structural Engineering and Mechanics, An Int'l Jou Vol.4 No.6

The paper reports on alternative hybrid/mixed formulations being developed by the Structural Analysis Research Group of Institute Superior T$\acute{e}$cnico. These formulations open the scope and increase the power of the finite element method by allowing different fields to be independently approximated, within certain consistency criteria, and by enhancing the use of a wide range of approximation functions. They have been applied to the analysis of 2-D problems, laminar structures and solids, using different constitutive relations, both in quasi-static and dynamic regimes. The fundamental properties of the formulations are identified and assessed and their performance is illustrated using simple, linear applications.

Prediction of Forming Limits Based on a Coupled Approach Between Anisotropic Damage and Necking Models

P. Teixeira,J.M.A. Cesar de Sa,A.D. Santos,F.M.A. Pires,A. Barata da Rocha 한국소성가공학회 2010 기타자료 Vol.2010 No.6

This article presents an integrated approach for localized necking and failure prediction in sheet metal forming processes, based on the coupling between the anisotropic damage evolution law proposed by Lemaitre [1] and the modified maximum force criterion (MMFC) proposed by Hora et al [2]. To illustrate the essential features of the coupled approach, an aluminum alloy has been selected and numerical predictions have been compared with experimental forming limits, obtained for both linear strain paths evolutions. Numerical results show that the introduction of the softening behavior, caused by the increase of damage, into the necking criterion can play a significant role in triggering local necking, providing an improved prediction of the necking occurrence together with the capability of performing calculations of limit strains when they are governed by fracture rather than by local necking.

Mineral Metabolism in Singleton and Twin-pregnant Dairy Goats

C.J. Harter,D.S. Castagnino,A.R. Rivera,L.D. Lima,H.G.O. Silva,A.N. Mendonca,G.F. Bonfim,A. Liesegang,N. St-Pierre,I.A.M.A. Teixeira 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.1

During pregnancy, the maternal body undergoes significant physiological changes. The present study assessed the changes on calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) metabolism in singleton and twin-pregnant dairy goats. The 42 goats used (49.5 kg±7.6 body weight [BW]) were assigned at random to treatments that were factorially arranged to account for 2 breeds (Oberhasli and Saanen), 2 pregnancy types (singleton and twin) and 3 gestation periods (80, 110, and 140 days). Digestibility trials were performed at 80, 110, and 140 days of gestation. Mineral retention during pregnancy was determined in the maternal body, femur, uterus, mammary gland, fetus and fetal fluid. Blood samples were taken during pregnancy before and after a meal, and Ca, P, Mg, Na, K ions and alkaline phosphatase activity determined in serum. Bone mineral density was determined in the right femur. Statistical analyses were performed using the SAS MIXED procedure. Dry matter intake decreased linearly up to 140 days of gestation. Maternal BW gain, and Ca, P, and Mg retention (g/kg) decreased linearly with the advance of gestation days. Macromineral retention in maternal body (g/kg) was greater in Oberhasli than Saanen goats, and their fetuses had higher Ca, P, and Mg deposition (mg/g). Mineral retention (mg/g) increased in fetuses according to pregnancy development, with no differences between singleton and twin pregnancy. In the mammary gland, the retention of all minerals (g) increased with the days of pregnancy. In conclusion, related to Ca, P, and Mg metabolism can be divided into two stages. Up to 80 days of gestation, was characterized by the preparation of the maternal body reserves for future mineral demands. From 80 days of gestation onward, was characterized by the transfer of maternal body reserves for fetal development and colostrum production. Na and K supply was provided by adjustments in endogenous excretion and an increase in intestinal absorption. Finally, mineral metabolism was specific to each genotype and, except for Na, was not affected by the number of fetuses.

Analysis of deep-subwavelength Au and Ag slit transmittances at terahertz frequencies

Park, J.-E.,Teixeira, F. L.,Borges, B.-H. V. Optical Society of America 2016 Journal of the Optical Society of America B Vol.33 No.7

<P>We provide a detailed characterization of the transmittance properties of subwavelength slit apertures on Ag and Au plates, as a function of the slit width and plate thickness, for frequencies ranging from 1.2 to 500 THz. As the method of analysis, we choose a mode-matching technique incorporating both discrete and continuum spectra because of its accuracy and suitability to this geometry. The transmittance behavior is shown to be strongly impacted by the variability of the electromagnetic bulk properties of Ag and Au across the terahertz range. The results obtained here constitute a useful compendium of reference data for subwavelength slit transmittances on metal plates at terahertz frequencies. (C) 2016 Optical Society of America</P>

Mineral Metabolism in Singleton and Twin-pregnant Dairy Goats

Harter, C.J.,Castagnino, D.S.,Rivera, A.R.,Lima, L.D.,Silva, H.G.O.,Mendonca, A.N.,Bonfim, G.F.,Liesegang, A.,St-Pierre, N.,Teixeira, I.A.M.A. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.1

During pregnancy, the maternal body undergoes significant physiological changes. The present study assessed the changes on calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) metabolism in singleton and twin-pregnant dairy goats. The 42 goats used ($49.5kg{\pm}7.6$ body weight [BW]) were assigned at random to treatments that were factorially arranged to account for 2 breeds (Oberhasli and Saanen), 2 pregnancy types (singleton and twin) and 3 gestation periods (80, 110, and 140 days). Digestibility trials were performed at 80, 110, and 140 days of gestation. Mineral retention during pregnancy was determined in the maternal body, femur, uterus, mammary gland, fetus and fetal fluid. Blood samples were taken during pregnancy before and after a meal, and Ca, P, Mg, Na, K ions and alkaline phosphatase activity determined in serum. Bone mineral density was determined in the right femur. Statistical analyses were performed using the SAS MIXED procedure. Dry matter intake decreased linearly up to 140 days of gestation. Maternal BW gain, and Ca, P, and Mg retention (g/kg) decreased linearly with the advance of gestation days. Macromineral retention in maternal body (g/kg) was greater in Oberhasli than Saanen goats, and their fetuses had higher Ca, P, and Mg deposition (mg/g). Mineral retention (mg/g) increased in fetuses according to pregnancy development, with no differences between singleton and twin pregnancy. In the mammary gland, the retention of all minerals (g) increased with the days of pregnancy. In conclusion, related to Ca, P, and Mg metabolism can be divided into two stages. Up to 80 days of gestation, was characterized by the preparation of the maternal body reserves for future mineral demands. From 80 days of gestation onward, was characterized by the transfer of maternal body reserves for fetal development and colostrum production. Na and K supply was provided by adjustments in endogenous excretion and an increase in intestinal absorption. Finally, mineral metabolism was specific to each genotype and, except for Na, was not affected by the number of fetuses.

The Curcumin Analog CH-5 Exerts Anticancer Effects in Human Osteosarcoma Cells via Modulation of Transcription Factors p53/Sp1

Lima, Felipe Teixeira,Seba, Viviane,Silva, Gabriel,Torrezan, Guilherme Silva,Polaquini, Carlos Roberto,Pinhanelli, Vitor Caressato,Baek, Seung J.,Fachin, Ana Lú,cia,Regasini, Luis Octavio,Marins MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.7

<P>Curcumin is a potential anticancer drug with poor bioavailability, which limits its clinical use as a therapeutic agent. The aim of this study was a preliminary evaluation of the curcumin analogue CH-5 as a cytotoxic agent in human osteosarcoma cell lines U2OS, MG-63, and Saos-2. CH-5 inhibited cell viability at lower concentrations than curcumin, leading to the induction of apoptosis. The cellular levels of the transcription factors p53 and Sp1 affect the expression of cellular pathways that lead to apoptosis. CH-5 increased p53 protein levels in U2OS cells and reduced Sp1 levels, with a consequent effect on the expression of their target genes DNA methyltransferase 1 (<I>DNMT1)</I> and growth arrest and DNA damage-inducible 45 alpha gene (<I>Gadd45a)</I>. CH-5 repressed <I>DNMT1</I> and increased <I>Gadd45a</I> mRNA expression, which was dependent on p53, as this effect was only observed in the colorectal cancer cell line HCT116 with active p53, but not in the isogenic p53-deficient HCT116 cells. CH-5 also reduced the protein levels of DNMT1, which led to the upregulation of <I>Gadd45a</I>. These results suggest that CH-5 has potentially higher anticancer activity than curcumin, which is associated with the expression of apoptosis-associated genes regulated by the transcription factors Sp1 and p53. Future work on CH-5 will define the therapeutic potential of this compound in vivo.</P>

Minimally Processing of Carambola (Averhoa carambola L.)

Gustavo Henrique A. Teixeira,Jose Fernando Durigan,Timothy J. O"Hare,Ricardo E. Alves 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

The role of geosciences in the assessment of low-temperature geothermal resources (N-Portugal): a review

José M. Marques,P.M. Carreira,J.E. Marques,H.I. Chaminé,P.E. Fonseca,F.A. Monteiro Santos,H.G.M. Eggenkamp,J. Teixeira 한국지질과학협의회 2010 Geosciences Journal Vol.14 No.4

The aim of this paper is to review the results of the assessment of low-temperature geothermal resources (issue temperatures between 41 and 77℃) that occur in the Portuguese mainland. For this purpose, a multidisciplinary approach, including geologic, tectonic, geochemical, geophysical and isotopic (2H, 18O, 13C, 3H and 14C) techniques, was applied in order to update local and/or regional conceptual circulation models. Three case studies of N-Portugal are presented and discussed. This paper describes different low-temperature geothermal waters presenting similar hydrogeological conceptual models but rather different geochemical signatures (e.g., HCO3–Na with pH 8, HCO3/Na/CO2-rich with pH 7 and HCO3–Na with pH 9, type waters). In fact, in the studied low-temperature geothermal systems, local/regional high altitude sites associated with highly fractured rocks play an important role in conducting the infiltrated meteoric waters towards the discharge zones near the Spas. The discharge zones are mainly related to the intersection of major regional fault lineaments (and conjugate structures), responsible for creating the mineral waters ascent. In some cases, geochemical and isotopic data point out to the existence of anthropogenic contamination of some geothermal spring waters related to the intense use of fertilizers in areas of widespread agricultural practices

Energy Requirements for Maintenance and Growth of Male Saanen Goat Kids

Medeiros, A.N.,Resende, K.T.,Teixeira, I.A.M.A.,Araujo, M.J.,Yanez, E.A.,Ferreira, A.C.D. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.9

The aim of study was to determine the energy requirements for maintenance and growth of forty-one Saanen, intact male kids with initial body weight (BW) of $5.12{\pm}0.19$ kg. The baseline (BL) group consisted of eight kids averaging $5.46{\pm}0.18$ kg BW. An intermediate group consisted of six kids, fed for ad libitum intake, that were slaughtered when they reached an average BW of $12.9{\pm}0.29$ kg. The remaining kids (n = 27) were randomly allocated into nine slaughter groups (blocks) of three animals distributed among three amounts of dry matter intake (DMI; ad libitum and restricted to 70% or 40% of ad libitum intake). Animals in a group were slaughtered when the ad libitum-treatment kid in the group reached 20 kg BW. In a digestibility trial, 21 kids (same animals of the comparative slaughter) were housed in metabolic cages and used in a completely randomized design to evaluate the energetic value of the diet at different feed intake levels. The net energy for maintenance ($NE_m$) was $417kJ/kg^{0.75}$ of empty BW (EBW)/d, while the metabolizable energy for maintenance ($ME_m$) was $657kJ/kg^{0.75}$ of EBW/d. The efficiency of ME use for NE maintenance ($k_m$) was 0.64. Body fat content varied from 59.91 to 92.02 g/kg of EBW while body energy content varied from 6.37 to 7.76 MJ/kg of EBW, respectively, for 5 and 20 kg of EBW. The net energy for growth ($NE_g$) ranged from 7.4 to 9.0 MJ/kg of empty weight gain by day at 5 and 20 kg BW, respectively. This study indicated that the energy requirements in goats were lower than previously published requirements for growing dairy goats.

Transmission Fiber Chromatic Dispersion Dependence on Temperature: Implications on 40 Gb/s Performance

Paulo S. André,Ant?io L. Teixeira,Armando N. Pinto,Lara P. Pellegrino,Berta B. Neto,J?e F Rocha,Jo? L. Pinto,Paulo N. Monteiro 한국전자통신연구원 2006 ETRI Journal Vol.28 No.2

In this letter, we will evaluate the performance degradation of a 40 km high-speed (40 Gb/s) optical system, induced by optical fiber variations of the chromatic dispersion induced by temperature changes. The chromatic dispersion temperature sensitivity will be estimated based on the signal quality parameters.