621 resultados para Givens rotations


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The prevalence of cardiometabolic diseases is a significant public health burden worldwide. Emerging evidence supports the inverse association between greater dairy consumption and reduced risk of cardiometabolic diseases. Dairy proteins may have in important role in the favourable impact of dairy on human health such as blood pressure (BP) control, blood lipid and glucose control. The purpose of this review is to update and critically evaluate the evidence on the impacts of casein and whey protein in relation to metabolic function. Evidence from acute clinical studies assessing postprandial responses to milk protein ingestion suggests benefits on vascular function independent of BP, as well as improvement in glycaemic homeostasis. Chronic interventions have been less conclusive, with some showing benefits and others indicating a lack of improvement in vascular function. During chronic consumption BP appears to be lowered and both dyslipidaemia and hyperglacaemia seems to be controlled. Limited number of trials investigated the effects of dairy proteins on oxidative stress and inflammation. The beneficial changes in cardiometabolic homeostasis are likely mediated through improvements in insulin resistance, however to gain more detailed understanding on the underlying mechanism of milk proteins warrants further research. The incorporation of meals enriched with dairy protein in the habitual diet may result in the beneficial effects on cardiometabolic health. Nevertheless, future well-designed, controlled studies are needed to investigate the relative effects of both casein and whey protein on BP, vascular function, glucose homeostasis and inflammation.

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Paleomagnetic and rockmagnetic data are reported for the Floresta Formation (Santa Fe Group) of the Sanfranciscana Basin, central Brazil. This formation represents the Permo-Carboniferous glacial record of the basin and comprises the Brocoto (diamictites and flow diamictites), Brejo do Arroz (red sandstones and shales with dropstones and invertebrate trails), and Lavado (red sandstones) members, which crop out near the cities of Santa Fe de Minas and Canabrava, Minas Gerais State. Both Brejo do Arroz and Lavado members were sampled in the vicinities of the two localities. Alternating field and thermal demagnetizations of 268 samples from 76 sites revealed reversed components of magnetization in all samples in accordance with the Permo-Carboniferous Reversed Superchron. The magnetic carriers are magnetite and hematite with both minerals exhibiting the same magnetization component, suggesting a primary origin for the remanence. We use the high-quality paleomagnetic pole for the Santa Fe Group (330.9 degrees E 65.7 degrees S; N = 60; alpha(95) = 4.1 degrees; k = 21) in a revised late Carboniferous to early Triassic apparent polar wander path for South America. On the basis of this result it is shown that an early Permian Pangea A-type fit is possible if better determined paleomagnetic poles become available.

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In this article we propose a 0-1 optimization model to determine a crop rotation schedule for each plot in a cropping area. The rotations have the same duration in all the plots and the crops are selected to maximize plot occupation. The crops may have different production times and planting dates. The problem includes planting constraints for adjacent plots and also for sequences of crops in the rotations. Moreover, cultivating crops for green manuring and fallow periods are scheduled into each plot. As the model has, in general, a great number of constraints and variables, we propose a heuristics based on column generation. To evaluate the performance of the model and the method, computational experiments using real-world data were performed. The solutions obtained indicate that the method generates good results.

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In this paper, we use Nuclear Magnetic Resonance (NMR) to write electronic states of a ferromagnetic system into high-temperature paramagnetic nuclear spins. Through the control of phase and duration of radio frequency pulses, we set the NMR density matrix populations, and apply the technique of quantum state tomography to experimentally obtain the matrix elements of the system, from which we calculate the temperature dependence of magnetization for different magnetic fields. The effects of the variation of temperature and magnetic field over the populations can be mapped in the angles of spin rotations, carried out by the RF pulses. The experimental results are compared to the Brillouin functions of ferromagnetic ordered systems in the mean field approximation for two cases: the mean field is given by (i) B = B(0) + lambda M and (ii) B = B(0) + lambda M + lambda`M(3), where B(0) is the external magnetic field, and lambda, lambda` are mean field parameters. The first case exhibits second order transition, whereas the second case has first order transition with temperature hysteresis. The NMR simulations are in good agreement with the magnetic predictions.

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We report 6 K-Ar ages and paleomagnetic data from 28 sites collected in Jurassic, Lower Cretaceous and Paleocene rocks of the Santa Marta massif, to test previous hypothesis of rotations and translations of this massif, whose rock assemblage differs from other basement-cored ranges adjacent to the Guyana margin. Three magnetic components were identified in this study. A first component has a direction parallel to the present magnetic field and was uncovered in all units (D 352, I = 25.6, k = 57.35, a95 = 5.3, N = 12). A second component was isolated in Cretaceous limestone and Jurassic volcaniclastic rocks (D = 8.8, I = 8.3, k = 24.71, a95 = 13.7, N = 6), and it was interpreted as of Early Cretaceous age. In Jurassic sites with this component, Early Cretaceous K-Ar ages obtained from this and previous studies are interpreted as reset ages. The third component was uncovered in eight sites of Jurassic volcaniclastic rocks, and its direction indicates negative shallow to moderate inclinations and northeastward declinations. K-Ar ages in these sites are of Early (196.5 +/- 4.9 Ma) to early Late Jurassic age (156.6 +/- 8.9 Ma). Due to local structural complexity and too few Cretaceous outcrops to perform a reliable unconformity test, we only used two sites with (1) K-Ar ages, (2) less structural complexity, and (3) reliable structural data for Jurassic and Cretaceous rocks. The mean direction of the Jurassic component is (D = 20.4, I = -18.2, k = 46.9, a95 = 5.1, n = 18 specimens from two sites). These paleomagnetic data support previous models of northward along-margin translations of Grenvillian-cored massifs. Additionally, clockwise vertical-axis rotation of this massif, with respect to the stable craton, is also documented; the sense of rotation is similar to that proposed for the Perija Range and other ranges of the southern Caribbean margin. More data is needed to confirm the magnitudes of rotations and translations. (C) 2009 Elsevier Ltd. All rights reserved.

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A paleomagnetic study was carried out on the Late Jurassic Sarmiento Ophiolitic Complex (SOC) exposed in the Magallanes fold and thrust belt in the southern Patagonian Andes (southern Chile). This complex, mainly consisting of a thick succession of pillow-lavas, sheeted dikes and gabbros, is a seafloor remnant of the Late Jurassic to Early Cretaceous Rocas Verdes basin that developed along the south-western margin of South America. Stepwise thermal and alternating field demagnetization permitted the isolation of a post-folding characteristic remanence, apparently carried by fine grain (SD?) magnetite, both in the pillow-lavas and dikes. The mean ""in situ"" direction for the SOC is Dec: 286.9 degrees, Inc: -58.5 degrees, alpha-95: 6.9 degrees, N: 11 (sites). Rock magnetic properties, petrography and whole-rock K-Ar ages in the same rocks are interpreted as evidence of correlation between remanence acquisition and a greenschist facies metamorphic overprint that must have occurred during latest stages or after closure and tectonic inversion of the basin in the Late Cretaceous. The mean remanence direction is anomalous relative to the expected Late Cretaceous direction from stable South America. Particularly, a declination anomaly over 50 degrees is suggestively similar to paleomagnetically interpreted counter clockwise rotations found in thrust slices of the Jurassic El Quemado Fm. located over 100 km north of the study area in Argentina. Nevertheless, a significant ccw rotation of the whole SOC is difficult to reconcile with geologic evidence and paleogeographic models that suggest a narrow back-arc basin sub-parallel to the continental margin. A rigid-body 30 degrees westward tilting of the SOC block around a horizontal axis trending NNW, is considered a much simpler explanation, being consistent with geologic evidence. This may have occurred as a consequence of inverse reactivation of old normal faults, which limit both the SOC exposures and the Cordillera Sarmiento to the East. The age of tilting is unknown but it must postdate remanence acquisition in the Late Cretaceous. Two major orogenic events of the southern Patagonian Andes, in the Eocene (ca. 42 Ma) and Middle Miocene (ca. 12 Ma), respectively, could have caused the proposed tilting. (C) 2008 Elsevier B.V. All rights reserved.

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A mixed integer continuous nonlinear model and a solution method for the problem of orthogonally packing identical rectangles within an arbitrary convex region are introduced in the present work. The convex region is assumed to be made of an isotropic material in such a way that arbitrary rotations of the items, preserving the orthogonality constraint, are allowed. The solution method is based on a combination of branch and bound and active-set strategies for bound-constrained minimization of smooth functions. Numerical results show the reliability of the presented approach. (C) 2010 Elsevier Ltd. All rights reserved.

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We investigate several two-dimensional guillotine cutting stock problems and their variants in which orthogonal rotations are allowed. We first present two dynamic programming based algorithms for the Rectangular Knapsack (RK) problem and its variants in which the patterns must be staged. The first algorithm solves the recurrence formula proposed by Beasley; the second algorithm - for staged patterns - also uses a recurrence formula. We show that if the items are not so small compared to the dimensions of the bin, then these algorithms require polynomial time. Using these algorithms we solved all instances of the RK problem found at the OR-LIBRARY, including one for which no optimal solution was known. We also consider the Two-dimensional Cutting Stock problem. We present a column generation based algorithm for this problem that uses the first algorithm above mentioned to generate the columns. We propose two strategies to tackle the residual instances. We also investigate a variant of this problem where the bins have different sizes. At last, we study the Two-dimensional Strip Packing problem. We also present a column generation based algorithm for this problem that uses the second algorithm above mentioned where staged patterns are imposed. In this case we solve instances for two-, three- and four-staged patterns. We report on some computational experiments with the various algorithms we propose in this paper. The results indicate that these algorithms seem to be suitable for solving real-world instances. We give a detailed description (a pseudo-code) of all the algorithms presented here, so that the reader may easily implement these algorithms. (c) 2007 Elsevier B.V. All rights reserved.

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The resolution of the natural racemic chromane 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3 ``-methyl-2 ``-butenyl)-2-(4`-methyl-1`,3`-pentadienyl)-2H-1-benzopyran-6-carboxylic acid (1) isolated from the leaves of Peperomia obtusifolia has been accomplished using stereoselective HPLC. The absolute coil figuration of the resolved enantiomers was determined by the analysis of optical rotations and CD spectra. The finding of a racemic mixture instead of an enantiomerically pure metabolite raises questions about the final steps in the biosynthesis of this class of natural products, suggesting that the intramolecular chromane ring formation step may not be enzymatically controlled at all in P. obtusifolia. Chirality 21:799-801, 2009. (C) 2008 Wiley-Liss, Inc.

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This degree project illustrates newsprint and waterless offset. A new news press was introduced at Drupa-00, Cortina from KBA, which is the first news press dedicated the waterless technique. With actual statistics from the company in question an investigation was made whether their production fits this press. It came out in the investigation that the production of the company, from statistics, fits this press very good. A table was made where different timeschedules were accounted for the new press, with semi- and full automatic plate changing for present and to be added papers. The waterless technology is compared to conventional offset with the difference that the plate is based on a sort of laminatetechnology. Like conventional plates this plate has a base made of aluminium. Lightsensitive photopolymer isunited as a layer or coat on top of the aluminium and a 2µm thin oleophobic siliconlayer is applied on top of the photopolymer. Considering the print, the waterless method has a higher qualitygrade than conventional offset. No water is emulsifiedin the ink, and therefore the printed dot gets a higher density. The loss of dampening solution and higher tack of the ink gives sharper dots. This makes the colourspace bigger why a greater range of colours can be printed. The loss of dampening solution gives a more stable dotgain, which contributes to that a higher screen can be used. The disadvantage is that the plate can't do as many rotations as the conventional plate. A waterless plate makes around 100 000-500 000 rotations before it needs to be removed owing to type- and manufacturer of the plate. The plate is also slightly more sensitive and expensive than conventional plates, around 1,4 - 1,7 × aluminium printing plates. A waterless system can be installed in a conventional printing press by degrees and when large editions are being printed a cooler needs to be installed in the oscillationrollers of the press, since an increase in temperature can make the oleophobic parts of the plate oleophilic. The Cortina is however equipped with a temperature controlsystem at the beginning. To avoid picking, caused by the tacky ink, a blanket with a high “quick release” should be used.

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Radioantenner tillverkas med olika egenskaper för att passa olika applikatoner. En av dessa egenskaper är antennens riktningskaraktäristik. Hur antennen skall konstrueras för att få den eftersträvade riktningskaraktäristiken kan beräknas. För att kontrollera att antennens faktiska riktningskaraktäristik överensstämmer med den beräknade kan antennens riktningskaraktäristik mätas. Företaget Detectus AB utvecklar idag ett mätsystem för att mäta antenners riktningskaraktäristik och presentera denna i form av ett tredimensionellt polärdiagram. Rapporten beskriver det examensarbete som genomförts i syfte att utveckla hårdvara med tillhörande styrsystem för mätsystemet. En prototyp för den rotortilt som skall rotera och tilta antennen under mätningen har utvecklats. Till denna rotortilt har också mjukvara för styrning av rotations- och tiltrörelsernas stegmotorer tagits fram. Vidare arbete innefattar att implementera en nödstoppsfunktion samt en referenssökningsfunktion för rotortilten. Vidare arbete innefattar också att utveckla mjukvara för mätsystemet.

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The Sagnac effect is an important phase coherent effect in optical and atom interferometers where rotations of the interferometer with respect to an inertial reference frame result in a shift in the interference pattern proportional to the rotation rate. Here, we analyze the Sagnac effect in a mesoscopic semiconductor electron interferometer. We include in our analysis the Rashba spin-orbit interactions in the ring. Our results indicate that spin-orbit interactions increase the rotation-induced phase shift. We discuss the potential experimental observability of the Sagnac phase shift in such mesoscopic systems.

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Lawrance (1991) has shown, through the estimation of consumption Euler equations, that subjective rates of impatience (time preference) in the U.S. are three to Öve percentage points higher for households with lower average labor incomes than for those with higher labor income. From a theoretical perspective, the sign of this correlation in a job-search model seems at Örst to be undetermined, since more impatient workers tend to accept wage o§ers that less impatient workers would not, thereby remaining less time unemployed. The main result of this paper is showing that, regardless of the existence of e§ects of opposite sign, and independently of the particular speciÖcations of the givens of the model, less impatient workers always end up, in the long run, with a higher average income. The result is based on the (unique) invariant Markov distribution of wages associated with the dynamic optimization problem solved by the consumers. An example is provided to illustrate the method.

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Sunflower is an annual dicotyledonous plant, herbaceous, erect and native of North America. It is thermo- and photo-insensitive, hence, can be grown round the year in sub-tropical and tropical countries. Only two spp. H. annuus and H. tuberosum are cultivated for food, remaining spp. are ornamentals, weeds and wild plants. However, H. annuus is allelopathic and inhibit the growth and development of other plants thus reducing their productivity. Much information is available about the allelopathic effects of sunflower crop on following crops in crop rotations. Although it is harmful to all crops, but, is less harmful to crops of Graminae family than other families. It seems that the harmful effects of sunflower in crop rotations are due to release and accumulation of root exudates during crop growth in soil. Soil incorporation of its fresh (green manure) or dry biomass in soil is inhibitory to both crops and weed spp. Several allelochemicals have been characterized from the H. annuus, which inhibit the seed germination and seedling growth of A. albus, A. viridis, Agropyron repens (Elymus repens), Ambrosia artemsiifolia, Avena fatua, Celosia crustata, Chenopodium album, Chloris barbara, Cynodon dactylon, D. sanguinalis, Dactyloctenium ageyptium, Digitaria ciliaris, Echinochloa crus-galli, Flaveria australasica, Parthenium hysterophorus, Portulaca oleracea, Sida spinosa, Trianthema portulacastrum, Veronica perisca the inhibitory effects of this crop may be used for weed management with less herbicides for sustainable agriculture.

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About two decades ago Brazil has been suffered some important political changes on its government and supporter systems. In these changes the Partido dos Trabalhadores (Workers support) has been researched significant results as much legislation as executive ways. These conquests propitiate a structure for it to get an alternative motion in order to manage public goods by petista government way. Trying to examinate this we can study the Partido dos Trabalhadores government experience in Acre (1999-2002) to know about why the PT government characteristics are different from the others. To do this we assumed to conjecture a popular participation with priorities inversion and ethics in public resources administration. These are the elements of PT government way. This way we started our work making an evaluation of its bibliography. Them we do a field inquiry to analyses documents of the government projects (budget rules law, papers, approved laws, IBGE, PNUD, TSE) and semi-structured interviews with some characters of recent political Acres life. The scheme and the analysis about these givens disclose that weren t confirmed our hypothesis in part, since PT remained old local politics habitus. In other side the executive administration on PT government has got to inflect the Governance . Further on an efficient management as World Bank dispossess but PT absolve many requests of progressive sectors as well it expanded the society participation to resolutions process. By a cabinets enlargement. So it rescues a total administrative course which is printed in the called petista government way. Personally we think so it means important advancements in this Acre government way