928 resultados para wall foundation
Multiple scales analysis of nonlinear oscillations of a portal frame foundation for several machines
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An analytical study of the nonlinear vibrations of a multiple machines portal frame foundation is presented. Two unbalanced rotating machines are considered, none of them resonant with the lower natural frequencies of the supporting structure. Their combined frequencies is set in such a way as to excite, due to nonlinear behavior of the frame, either the first anti-symmetrical mode (sway) or the first symmetrical mode. The physical and geometrical characteristics of the frame are chosen to tune the natural frequencies of these two modes into a 1:2 internal resonance. The problem is reduced to a two degrees of freedom model and its nonlinear equations of motions are derived via a Lagrangian approach. Asymptotic perturbation solutions of these equations are obtained via the Multiple Scales Method.
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This work presents a new law of the wall formulation for recirculating turbulent flows. An alternative expression for the internal length which can be applied in the separated region is also presented. The formulation is implemented in a numerical code which solves the k-epsilon model through a finite volume method. The theoretical results are compared with the experimental data of Vogel and Eaton (J. of Heat Transfer, Transactions of ASME, vol.107, pp. 922-929, 1985). The paper shows that the present formulation furnishes better results than the standard k-epsilon formulation.
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An experimental investigation is performed in a turbulent flow in a seven wire-wrapped rod bundle, mounted in an open air facility. Static pressure distributions are measured on central and peripheral rods. By using a Preston tube, the wall shear stress profiles are experimentally obtained along the perimeter of the rods. The geometric parameters of the test section are P/D=1.20 and H/D=15. The measuring section is located at L/D=40 from the air inlet. It is observed that the dimensionless static pressure and wall shear stress profiles are nearly independent of the Reynolds number and strongly dependent of the wire-spacer position, with abrupt variations of the parameters in the neighborhood of the wires.
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Dialypetalanthus fuscescens is an Amazonian endemic species with problematic taxonomic position. This neotropical rainforest tree belongs to the monospecific Dialypetalanthaceae. In the present work, we analysed the leaf cell-wall polysaccharide composition of Dialypetalanthus fuscescens and compared it to that of Bathysa meridionalis (Rubiaceae-Cinchonoideae). Glycosyl composition and glycosyl-linkage analysis indicated that both species have similar cell wall composition. Arabinogalactans were the major component of the pectic polysaccharides and xylans, although being reported in minor amounts in dicots, were found to be the predominant hemicellulosic polysaccharide in cell walls of both species. These findings are in agreement with previous data on cell wall composition reported for Rubiaceae and corroborate the current suggestion of the possible link between this family and Dialypetalanthaceae.
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O gênero Staurogyne Wall. reúne cerca de 140 espécies tropicais, com 28 destas reconhecidas para os neotrópicos, encontradas principalmente em áreas florestais preservadas. A revisão atualizada do gênero para as Américas revelou quatro espécies inéditas para o território brasileiro, aqui descritas. Os novos táxons são conhecidos para os Estados de Goiás, Minas Gerais, Espírito Santo, São Paulo, Rio de Janeiro, Paraná e Santa Catarina, três na Floresta Pluvial Atlântica, e uma nas matas de galeria, nos domínios do cerrado.
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The role gap junction channels play in the normal and abnormal functioning of the vascular wall is the subject of much research. The biophysical properties of gap junctions are an essential component in understanding how gap junctions function to allow coordinated relaxation and contraction of vascular smooth muscle. This study reviews the properties thus far elucidated and relates those properties to tissue function. We ask how biophysical and structural properties such as gating, permselectivity, subconductive states and channel type (heteromeric vs homotypic vs heterotypic) might affect vascular smooth muscle tone.
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An alkali-insoluble fraction 1 (F1), which contains mainly ß-glucan isolated from the cell wall of Histoplasma capsulatum, induces eosinophil recruitment into the peritoneal cavity of mice. The present study was carried out to determine the participation of interleukin-5 (IL-5) in this process. Inbred C57BL/6 male mice weighing 15-20 g were treated ip with 100 µg of anti-IL-5 monoclonal antibody (TRFK-5, N = 7) or an isotype-matched antibody (N = 7), followed by 300 µg F1 in 1 ml PBS ip 24 h later. Controls (N = 5) received only 1 ml PBS. Two days later, cells from the peritoneal cavity were harvested by injection of 3 ml PBS and total cell counts were determined using diluting fluid in a Neubauer chamber. Differential counts were performed using Rosenfeld-stained cytospin preparations. The F1 injection induced significant (P < 0.01) leukocyte recruitment into the peritoneal cavity (8.4 x 10(6) cells/ml) when compared with PBS alone (5.5 x 10(6) cells/ml). Moreover, F1 selectively (P < 0.01) induced eosinophil recruitment (1 x 10(6) cells/ml) when compared to the control group (0.07 x 10(6) cells/ml). Treatment with TRFK-5 significantly (P < 0.01) inhibited eosinophil recruitment (0.18 x 10(6) cells/ml) by F1 without affecting recruitment of mononuclear cells or neutrophils. We conclude that the F1 fraction of the cell wall of H. capsulatum induces peritoneal eosinophilia by an IL-5-dependent mechanism. Depletion of this cytokine does not have effect on the recruitment of other cell types induced by F1.
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Quire structure: 9xIV⁷² + (IV–1)⁷⁹. Text in one column, on (mostly) 26–33 lines, not ruled. Catchwords frequently used at the foot of each page to indicate the next word when a sentence continues on the next page. Not foliated. Gothic Cursive in one saec. XVI² hand. The first initial of the book has been touched with what looks like red pencil. This may be a later addition, as also the green tint to the outer edges of the block. Titles and rubrics distinguished, if at all, through layout only. A note fol. [47]v (see also the main text on fol. [31]v) indicates that the text was copied in 1580. The Anti-Papist poem mentions the Jesuit Antonio Possevino, active in Sweden in 1577–1580 (Kiiskinen ed. 2010, 25, 27). The texts appear to be copies of printed works, with the possible exception of the Anti-Papist poem. The publication of Eric Falck’s Een Tröstbook is known, but apparently no printed copies survive; Laurentius Olai Gestricius’ catechism is otherwise unknown. He was a teacher in Gävle from 1557 or 1558, then curate of Västerås from 1561 and of Stockholm in 1562, where he died in 1565 (Kiiskinen ed. 2010, 15, 349; Collijn ed. 1927–1938, vol. 2, 324).
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The present study describes an auxiliary tool in the diagnosis of left ventricular (LV) segmental wall motion (WM) abnormalities based on color-coded echocardiographic WM images. An artificial neural network (ANN) was developed and validated for grading LV segmental WM using data from color kinesis (CK) images, a technique developed to display the timing and magnitude of global and regional WM in real time. We evaluated 21 normal subjects and 20 patients with LVWM abnormalities revealed by two-dimensional echocardiography. CK images were obtained in two sets of viewing planes. A method was developed to analyze CK images, providing quantitation of fractional area change in each of the 16 LV segments. Two experienced observers analyzed LVWM from two-dimensional images and scored them as: 1) normal, 2) mild hypokinesia, 3) moderate hypokinesia, 4) severe hypokinesia, 5) akinesia, and 6) dyskinesia. Based on expert analysis of 10 normal subjects and 10 patients, we trained a multilayer perceptron ANN using a back-propagation algorithm to provide automated grading of LVWM, and this ANN was then tested in the remaining subjects. Excellent concordance between expert and ANN analysis was shown by ROC curve analysis, with measured area under the curve of 0.975. An excellent correlation was also obtained for global LV segmental WM index by expert and ANN analysis (R² = 0.99). In conclusion, ANN showed high accuracy for automated semi-quantitative grading of WM based on CK images. This technique can be an important aid, improving diagnostic accuracy and reducing inter-observer variability in scoring segmental LVWM.
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Recent data from our laboratory have shown that patients with the indeterminate form of Chagas' disease can have impairment of left ventricular contractility, as evaluated by the slope of the left ventricle end-systolic pressure-dimension relationship. We also showed that Chagas' disease patients with minimal baseline wall motion abnormalities detected by two-dimensional echocardiography have more intense contractility impairment when compared to patients with the indeterminate form of the disease without this abnormality. The prognostic implications of these findings have not been established. We evaluated 59 patients (37-76 years, mean = 55 years) with different clinical forms of Chagas' disease, who had normal left ventricular global systolic function at baseline (57.6 ± 6.9%) and who had at least one additional echo during clinical follow-up (0.4-17.6; mean 4.6 years). Group 1 consisted of 14 patients with minor baseline left ventricle wall motion abnormalities and group 2 consisted of 45 patients without these abnormalities. During follow-up, global left ventricle systolic function deterioration was observed in 10 group 1 patients (71.4%) and in only 10 group 2 patients (22.2%; P < 0.005). Age and duration of follow-up were not independent determinants of left ventricular function deterioration in these patients. The present data indicate that mild segmental left ventricular wall motion abnormalities are associated with worsening of systolic function in Chagas' disease patients who have normal baseline global systolic performance.
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The objective of this study was to determine the inter- and intra-examiner reliability of pain pressure threshold algometry at various points of the abdominal wall of healthy women. Twenty-one healthy women in menacme with a mean age of 28 ± 5.4 years (range: 19-39 years) were included. All volunteers had regular menstrual cycles (27-33 days) and were right-handed and, to the best of our knowledge, none were taking medications at the time of testing. Women with a diagnosis of depression, anxiety or other mood disturbances were excluded. Women with previous abdominal surgery, any pain condition or any evidence of inflammation, hypertension, smoking, alcoholism, or inflammatory disease were also excluded. Pain perception thresholds were assessed with a pressure algometer with digital traction and compression and a measuring capacity for 5 kg. All points were localized by palpation and marked with a felt-tipped pen and each individual was evaluated over a period of 2 days in two consecutive sessions, each session consisting of a set of 14 point measurements repeated twice by two examiners in random sequence. There was no statistically significant difference in the mean pain threshold obtained by the two examiners on 2 diferent days (examiner A: P = 1.00; examiner B: P = 0.75; Wilcoxon matched pairs test). There was excellent/good agreement between examiners for all days and all points. Our results have established baseline values to which future researchers will be able to refer. They show that pressure algometry is a reliable measure for pain perception in the abdominal wall of healthy women.
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This study evaluated the dynamic behavior of total and compartmental chest wall volumes [(V CW) = rib cage (V RC) + abdomen (V AB)] as measured breath-by-breath by optoelectronic plethysmography during constant-load exercise in patients with stable chronic obstructive pulmonary disease. Thirty males (GOLD stages II-III) underwent a cardiopulmonary exercise test to the limit of tolerance (Tlim) at 75% of peak work rate on an electronically braked cycle ergometer. Exercise-induced dynamic hyperinflation was considered to be present when end-expiratory (EE) V CW increased in relation to resting values. There was a noticeable heterogeneity in the patterns of V CW regulation as EEV CW increased non-linearly in 17/30 "hyperinflators" and decreased in 13/30 "non-hyperinflators" (P < 0.05). EEV AB decreased slightly in 8 of the "hyperinflators", thereby reducing and slowing the rate of increase in end-inspiratory (EI) V CW (P < 0.05). In contrast, decreases in EEV CW in the "non-hyperinflators" were due to the combination of stable EEV RC with marked reductions in EEV AB. These patients showed lower EIV CW and end-exercise dyspnea scores but longer Tlim than their counterparts (P < 0.05). Dyspnea increased and Tlim decreased non-linearly with a faster rate of increase in EIV CW regardless of the presence or absence of dynamic hyperinflation (P < 0.001). However, no significant between-group differences were observed in metabolic, pulmonary gas exchange and cardiovascular responses to exercise. Chest wall volumes are continuously regulated during exercise in order to postpone (or even avoid) their migration to higher operating volumes in patients with COPD, a dynamic process that is strongly dependent on the behavior of the abdominal compartment.
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Follicle cultures reproduce in vitro the functional features observed in vivo. In a search for an ideal model, we cultured bovine antral follicle wall sections (FWS) in a serum-free defined medium (DM) known to induce 17β-estradiol (E2) production, and in a nondefined medium (NDM) containing serum. Follicles were sectioned and cultured in NDM or DM for 24 or 48 h. Morphological features were determined by light microscopy. Gene expression of steroidogenic enzymes and follicle-stimulating hormone (FSH) receptor were determined by RT-PCR; progesterone (P4) and E2 concentrations in the media were measured by radioimmunoassay. DM, but not NDM, maintained an FWS morphology in vitro that was similar to fresh tissue. DM also induced an increase in the expression of all steroidogenic enzymes, except FSH receptor, but NDM did not. In both DM and NDM, there was a gradual increase in P4 throughout the culture period; however, P4 concentration was significantly higher in NDM. In both media, E2 concentration was increased at 24 h, followed by a decrease at 48 h. The E2:P4 ratio was higher in DM than in NDM. These results suggest that DM maintains morphological structure, upregulates the expression of steroidogenic enzyme genes, and maintains steroid production with a high E2:P4 ratio in FWS cultures.
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The soluble and insoluble cotyledon (SPF-Co and IPF-Co) and tegument (SPF-Te and IPF-Te) cell wall polymer fractions of common beans (Phaseolus vulgaris) were isolated using a chemical-enzymatic method. The sugar composition showed that SPF-Co was constituted of 38.6% arabinose, 23.4% uronic acids, 12.7% galactose, 11.2% xylose, 6.4% mannose and 6.1% glucose, probably derived from slightly branched and weakly bound polymers. The IPF-Co was fractionated with chelating agent (CDTA) and with increasing concentrations of NaOH. The bulk of the cell wall polymers (29.4%) were extracted with 4.0M NaOH and this fraction contained mainly arabinose (55.0%), uronic acid (18.9%), glucose (10.7%), xylose (10.3%) and galactose (3.4%). About 8.7% and 10.6% of the polymers were solubilised with CDTA and 0.01M NaOH respectively and were constituted of arabinose (52.0 and 45.9%), uronic acids (25.8 and 29.8%), xylose (9.6 and 10.2%), galactose (6.1 and 3.9%) and glucose (6.5 and 3.8%). The cell wall polymers were also constituted of small amounts (5.6 and 7.2%) of cellulose (CEL) and of non-extractable cell wall polymers (NECW). About 16.8% and 17.2% of the polymers were solubilised with 0.5 and 1.0M NaOH and contained, respectively, 92.1 and 90.7% of glucose derived from starch (IST). The neutral sugar and polymers solubilization profiles showed that weakly bound pectins are present mainly in SPF-Co (water-soluble), CDTA and 0.01-0.1M NaOH soluble fractions. Less soluble, highly cross-linked pectins were solubilised with 4.0M NaOH. This pectin is arabinose-rich, probably highly branched and has a higher molecular weight than the pectin present in SPF-Co, CDTA and 0.01-0.1M NaOH fractions.
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Starch derivatives of taro (Colocasia esculenta L. Schott) and rice were characterized as wall materials of orange oil (d-limonene) by spray drying. Native starches were initially hydrolyzed with HCl and then esterified. Succinylated starches were modified using a conventional method in a slurry and were extruded; whereas, the phosphorylated starches were modified using the extrusion process. Viscosity and solubility of starches reduced after acid hydrolysis, derivatization, and extrusion. The particle size of the wall materials ranged between 20.05 and 31.81 µm. The encapsulation efficiency of the phosphorylated taro, rice, and waxy corn starches was 96.9, 96.8 and 97.1% respectively, and 98.6, 98.1, and 98.8% for succynilated taro, rice, and waxy corn starches, respectively. Starch derivatives of taro and rice could potentially be used as wall materials of orange oil d-limonene.