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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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During the last 30 years the Atomic Force Microscopy became the most powerful tool for surface probing in atomic scale. The Tapping-Mode Atomic Force Microscope is used to generate high quality accurate images of the samples surface. However, in this mode of operation the microcantilever frequently presents chaotic motion due to the nonlinear characteristics of the tip-sample forces interactions, degrading the image quality. This kind of irregular motion must be avoided by the control system. In this work, the tip-sample interaction is modelled considering the Lennard-Jones potentials and the two-term Galerkin aproximation. Additionally, the State Dependent Ricatti Equation and Time-Delayed Feedback Control techniques are used in order to force the Tapping-Mode Atomic Force Microscope system motion to a periodic orbit, preventing the microcantilever chaotic motion

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The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

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The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

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We evaluated the effect of gamma irradiation doses (0, 125, 250, and 500 Gy) in control of psychrotrophic bacteria in different strains of Agaricus bisporus (ABI-07/06, ABI-05/03, and PB-1) during storage, cultivated in composts based on oat straw (Avena sativa) and Brachiaria spp. The experimental design was completely randomized in a factorial scheme 4  2  3 (irradiation doses  composts  strains), with 24 treatments, each consisting of 2 replicates, totaling 48 experimental units (samples of mushrooms). The mushrooms collected from all culture conditions were packaged in plastic polypropylene with 200 g each and subjected to Cobalt-60 irradiator, type Gammacell 220, and dose rate 0.740 kGy h–1 , according to the treatments. Subsequently, the control (nonirradiated) and other treatments were maintained at 4 ± 1°C and 90% relative humidity (RH) in a climatic chamber to perform the microbiological analysis of mushrooms on the 1st and 14th day of storage. According to the results, it was found that the highest mean colony psychotrophic count, after 14 days of storage, was observed in strain ABI-07/06 1.30 × 108 g -1 most probable number (MPN) in nonirradiated mushrooms, coming from Brachiaria grass-based compost, and this same strain under the same storage conditions, coming from the same type of compost that underwent a dose of 500 Gy, obtained a significant reduction in mean colonies of psychrotrophic bacteria (2.25 × 104 g –1 MPN). Thus, the irradiation doses tested favored reducing the number of colonies of psychrotrophic bacteria, regardless of the type of compound and strain of A. bisporus.

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This paper had the objective of determining the transition regions between the juvenile and mature wood of Corymbia citriodora (Eucalyptus citriodora) of 29 years of age from the Experimental Station of Forest Science (EECFA-LCF/ESALQ-USP), located in Anhembi, in the State of São Paulo. The regions of juvenile and mature wood were characterized through anatomical studies - axial fiber length - following the recommendations of the International Association of Wood Anatomists (1989) using disks at the DBH of the trees. The measurements of fiber length were made in equipment for acquisition, diagnosis and image analysis. Five slices were made for every centimeter, in the radial direction and six fiber lengths per slice were measured, producing 30 measurements per sample region. In the total, 1740 lengths of fiber were measured in three disks that were studied. Results indicate a trend of accentuated and linear increase for the length of fibers, from the pith to 11 cm of radial of about 79%. Between 12 cm and 19 cm of the radius, fibers length remained almost constant, and from that point on, the fiber length tended to slightly increase to the bark. It can be concluded that for these trees, at this height of sampling, when the tree has 29 years of age, the extension of the juvenile wood goes up to 52% of its radius.

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O alumínio (Al) em solos ácidos encontra-se na forma Al3+, sendo considerado tóxico às plantas de interesse agronômico, como o limoeiro Cravo (Citrus limonia), afetando principalmente seu crescimento radicular . O presente estudo avaliou como o Al influencia as raízes de C. limonia, visando correlacionar a concentração endógenea de IAA, a expressão dos genes SAUR X10A e SAUR 15A e a inibição do crescimento radicular. As plantas foram submetidas à hidroponia em diferentes concentrações de Al na solução nutritiva (0, 370 μM, 740 μM, 1110 μM, e 1480), tendo seu crescimento avaliado semanalmente em um período de dois meses. Além disso, as soluções contrastantes tiveram a expressão gênica e a concentração endógenea de IAA avaliados utilizando qRT-PCR e GC-MS, respectivamente. O tratamento com Al inibiu o crescimento radicular das plantas, além de alterar a concentração de IAA nas raízes (apresentou-se algumas vezes maior nas primeiras semanas em relação ao controle, havendo um decaimento e igualação na concentração hormonal de ambos os tratamentos) e inibir a expressão dos genes SAUR. A inibição do crescimento radicular pode ser atribuida à uma mudança de padrão e acumulação do ácido indol-acético (IAA) no ápice da raiz, provocada pela alteração na distribuição das proteínas de transporte. Concomitantemente, proteínas da família SAUR (small auxin-up RNA) têm suas expressões gênicas induzidas em presença de IAA e estão relacionadas à acidificação do apoplasto: a queda na atividade da H+-ATPase provoca a altereção do pH nesta região prejudicando a alongação da célula via crescimento ácido. Embora haja uma mesma quantidade de IAA na raiz, os genes SAUR são reprimidos na condição de estresse pelo Al, indicando que a inibição do crescimento radicular em C. limonia deve ocorrer em resposta a um conjunto de fatores

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Between 1991 and 1993, Alaska harbor porpoise (Phocoena phocoena) abundance was investigated during aerial surveys throughout much of the coastal and offshore waters from Bristol Bay in the eastern Bering Sea to Dixon Entrance in Southeast Alaska. Line-transect methodology was used, and only those observations made during optimal conditions were analyzed. Survey data indicated densities of 4.48 groups/100 km2, or approximately 3,531 harbor porpoises (95% C.I. 2,206-5,651) in Bristol Bay and 0.54 groups/100 km2, or 136 harbor porpoises (95% C.I. 11-1,645) for Cook Inlet. Efforts off Kodiak Island resulted in densities of 1.85 groups/100 km2, or an abundance estimate of 740 (95% C.I. 259-2,115). Surveys off the south side of the Alaska Peninsula found densities of 2.03 groups/100 km2 and an abundance estimate of 551 (95% C.I. 423-719). Surveys of offshore waters from Prince William Sound to Dixon Entrance yielded densities of 4.02 groups/100 km’ and an abundance estimate of 3,982 (95% C.I. 2,567-6,177). Combining all years and areas yielded an uncorrected density estimate of 3.82 porpoises per 100 km2, resulting in an abundance estimate of 8,940 porpoises (CV = 13.8%) with a 95% confidence interval of 6,746-11,848. Using correction factors from other studies to adjust for animals missed by observers, the total number of Alaska harbor porpoises is probably three times this number.

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O alumínio (Al) em solos ácidos encontra-se na forma Al3+, sendo considerado tóxico às plantas de interesse agronômico, como o limoeiro Cravo (Citrus limonia), afetando principalmente seu crescimento radicular . O presente estudo avaliou como o Al influencia as raízes de C. limonia, visando correlacionar a concentração endógenea de IAA, a expressão dos genes SAUR X10A e SAUR 15A e a inibição do crescimento radicular. As plantas foram submetidas à hidroponia em diferentes concentrações de Al na solução nutritiva (0, 370 μM, 740 μM, 1110 μM, e 1480), tendo seu crescimento avaliado semanalmente em um período de dois meses. Além disso, as soluções contrastantes tiveram a expressão gênica e a concentração endógenea de IAA avaliados utilizando qRT-PCR e GC-MS, respectivamente. O tratamento com Al inibiu o crescimento radicular das plantas, além de alterar a concentração de IAA nas raízes (apresentou-se algumas vezes maior nas primeiras semanas em relação ao controle, havendo um decaimento e igualação na concentração hormonal de ambos os tratamentos) e inibir a expressão dos genes SAUR. A inibição do crescimento radicular pode ser atribuida à uma mudança de padrão e acumulação do ácido indol-acético (IAA) no ápice da raiz, provocada pela alteração na distribuição das proteínas de transporte. Concomitantemente, proteínas da família SAUR (small auxin-up RNA) têm suas expressões gênicas induzidas em presença de IAA e estão relacionadas à acidificação do apoplasto: a queda na atividade da H+-ATPase provoca a altereção do pH nesta região prejudicando a alongação da célula via crescimento ácido. Embora haja uma mesma quantidade de IAA na raiz, os genes SAUR são reprimidos na condição de estresse pelo Al, indicando que a inibição do crescimento radicular em C. limonia deve ocorrer em resposta a um conjunto de fatores

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Background & aims: Altered intestinal permeability has been shown to be associated with metabolic alterations in animal models of obesity, but not in humans. The aim of this study was to assess intestinal permeability in obese women and verify if there is any association with anthropometric measurements, body composition or biochemical variables. Methods: Twenty lean and twenty obese females participated in the study. Anthropometric measurements, body composition and blood pressure were assessed and biochemical analyses were performed. Administration of lactulose and mannitol followed by their quantification in urine was used to assess the intestinal permeability of volunteers. Results: The obese group showed lower HDL (p < 0.05), higher fasting glucose, insulin, HOMA index and lactulose excretion than the lean group (p < 0.05), suggesting increased paracellular permeability. Lactulose excretion showed positive correlation (p < 0.05) with waist and abdominal circumference. Blood insulin and the HOMA index also increased with the increase in mannitol and lactulose excretion and in the L/M ratio (p < 0.05). L/M ratio presented a negative correlation with HDL concentration (p < 0.05). Conclusions: We demonstrated that intestinal permeability parameters in obese women are positively correlated with anthropometric measurements and metabolic variables. Therapeutic interventions focused on intestine health and the modulation of intestinal permeability should be explored in the context of obesity. (C) 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

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We present the results of an operational use of experimentally measured optical tomograms to determine state characteristics (purity) avoiding any reconstruction of quasiprobabilities. We also develop a natural way how to estimate the errors (including both statistical and systematic ones) by an analysis of the experimental data themselves. Precision of the experiment can be increased by postselecting the data with minimal (systematic) errors. We demonstrate those techniques by considering coherent and photon-added coherent states measured via the time-domain improved homodyne detection. The operational use and precision of the data allowed us to check purity-dependent uncertainty relations and uncertainty relations for Shannon and Renyi entropies.

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Knowledge of hospital costs is highly important for public health decision-making. This study aimed to estimate direct hospital costs related to pneumococcal meningitis in children 13 years or younger in the city of Sao Jose dos Campos, Sao Paulo State, Brazil, from January 1999 to December 2008. Data were obtained from medical records. Hospital costs were calculated according to the mixed method for measurement of quantities of items with identified costs and value attribution to items consumed (micro-costing and gross-costing). All costs were calculated according to monetary values for November 2009 and in Brazilian currency (Real). Epi Info 3.5.1 was used for frequencies and means analysis. Forty-one cases were reported. Direct hospital costs varied from R$ 1,277.90 to R$ 19,887.56 (mean = R$ 5,666.43), or 10 to 20 times the mean cost of hospitalization for other diseases. Hospital staff labor was the highest cost, followed by medication, procedures, supplies, and lab tests.

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The structure of additional electromagnetic fields to the Aharonov-Bohm field, for which the Schrodinger, Klein-Gordon, and Dirac equations can be solved exactly are described and the corresponding exact solutions are found. It is demonstrated that aside from the known cases (a constant and uniform magnetic field that is parallel to the Aharonov-Bohm solenoid, a static spherically symmetrical electric field, and the field of a magnetic monopole), there are broad classes of additional fields. Among these new additional fields we have physically interesting electric fields acting during a finite time or localized in a restricted region of space. There are additional time-dependent uniform and isotropic electric fields that allow exact solutions of the Schrodinger equation. In the relativistic case there are additional electric fields propagating along the Aharonov-Bohm solenoid with arbitrary electric pulse shape. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714352]

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This paper completes our study of coherent states in the so-called magnetic-solenoid field (a collinear combination of a constant uniform magnetic field and Aharonov-Bohm solenoid field) presented in Bagrov et al (2010 J. Phys. A: Math. Theor. 43 354016, 2011 J. Phys. A: Math. Theor. 44 055301). Here, we succeeded in proving nontrivial completeness relations for non-relativistic and relativistic coherent states in such a field. In addition, we solve here the relevant Stieltjes moment problem and present a comparative analysis of our coherent states and the well-known, in the case of pure uniform magnetic field, Malkin-Man'ko coherent states.

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We present a detailed study of the Baryscan technique, a new efficient alternative to the widespread Z-scan technique which has been demonstrated [Opt. Lett. 36:8, 2011] to reach among the highest sensitivity levels. This method is based upon the measurement of optical nonlinearities by means of beam centroid displacements with a position sensitive detector and is able to deal with any kind of lensing effect. This technique is applied here to measure pump-induced electronic refractive index changes (population lens), which can be discriminated from parasitic thermal effects by using a time-resolved Baryscan experiment. This method is validated by evaluating the polarizability variation at the origin of the population lens observed in the reference Cr3+:GSGG laser material.