Optimal and sub-optimal control in Dengue epidemics

This work concerns the application of the optimal control theory to Dengue epidemics. The dynamics of this insect-borne disease is modelled as a set of non-linear ordinary differential equations including the effect of educational campaigns organized to motivate the population to break the reproduction cycle of the mosquitoes by avoiding the accumulation of still water in open-air recipients. The cost functional is such that it reflects a compromise between actual financial spending (in insecticides and educational campaigns) and the population health (which can be objectively measured in terms of, for instance, treatment costs and loss of productivity). The optimal control problem is solved numerically using a multiple shooting method. However, the optimal control policy is difficult to implement by the health authorities because it is not practical to adjust the investment rate continuously in time. Therefore, a suboptimal control policy is computed assuming, as the admissible set, only those controls which are piecewise constant. The performance achieved by the optimal control and the sub-optimal control policies are compared with the cases of control using only insecticides when Breteau Index is greater or equal to 5 and the case of no-control. The results show that the sub-optimal policy yields a substantial reduction in the cost, in terms of the proposed functional, and is only slightly inferior to the optimal control policy. Copyright (C) 2001 John Wiley & Sons, Ltd.

Multi-functional properties of CaCu3Ti4O12 thin films

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Multiloop superstring amplitudes from non-minimal pure spinor formalism

Using the non-minimal version of the pure spinor formalism, manifestly super-Poincare covariant superstring scattering amplitudes can be computed as in topological string theory without the need of picture-changing operators. The only subtlety comes from regularizing the functional integral over the pure spinor ghosts. In this paper, it is shown how to regularize this functional integral in a BRST-invariant manner, allowing the computation of arbitrary multiloop amplitudes. The regularization method simplifies for scattering amplitudes which contribute to ten-dimensional F-terms, i.e. terms in the ten-dimensional superspace action which do not involve integration over the maximum number of theta's.

The influence of the thickness on the functional properties of cassava starch edible films

The properties of edible films are influenced by several factors, including thickness. The purpose of this paper was to study the influence of thickness on the viscoelasticity properties, water vapor permeability, color and opacity of cassava starch edible films. These films were prepared by a casting technique, the film-forming solutions were 1, 2, 3 and 4% (w/v) of starch, heated to 70degreesC. Different thicknesses were obtained by putting 15 to 70 g of each solution on plexiglass plates. After drying at 30degreesC and ambient relative humidity, these samples were placed for 6 days at RH of 75%, at 22degreesC. The sample thicknesses were determined by a digital micrometer (+/-0.001 mm), as the average of nine different points. The viscoelasticity properties were determined by stress relaxation tests with a texture analyser TA.XT2i (SMS), being applied the Burgers model of four parameters. The water vapor permeability was determined with a gravimetric method, and color and opacity were determined using a Miniscan XE colorimeter, operated according to the Hunterlab method. All the tests were carried out in duplicate at 22degreesC. Practically, the four visco-elasticity properties calculated by the Burgers model had the same behavior, increasing with the thickness of all films, according to a power law model. The water vapor permeability and the color difference increased linearly with the thickness (0.013-0.144 mm) of all films prepared with solution of 1 to 4% of starch. on the other hand, the effect of the variation of the thickness over the opacity, was more important in the films with 1 and 2% of starch. It can be concluded that the control of the thickness in the elaboration of starch films by the casting technique is of extreme importance.

Alterations in pulmonary structure by elastase administration in a model of emphysema in mice is associated with functional disturbances

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Effects of N Helix Deletion and Mutant F29W on the Ca2+ Binding and Functional Properties of Chicken Skeletal Muscle Troponin C

To assess the structural and functional significance of the N helix (residues 3-13) of avian recombinant troponin C (rTnC), we have constructed NHdel, in which residues 1-11 have been deleted, both in rTnC and in the spectral probe mutant F29W (Pearlstone, J. R., Borgford, T., Chandra, M., Oikawa, K., Kay, C. M., Herzberg, O., Moult, J., Herklotz, A., Reinach, F. C., and Smillie, L.B. (1992) Biochemistry 31, 6545-6553). Comparison of the far- and near-UV CD spectra (±Ca2+) of F29W and F29W/ NHdel and titration of the Ca2+-induced ellipticity and fluorescence changes indicates that the deletion has little effect on the global fold of the molecule but reduces the Ca2+ affinity of the N domain, but not the C domain, by 1.6-1.8-fold. Comparisons of the mutants NHdel, F29W, and F29W/NHdel with rTnC have been made using several functional assays. In reconstituted troponin-tropomyosin actomyosin subfragment 1 and myofibrillar ATPase systems, both F29W and NHdel have significantly reduced Ca2+-activated enzymic activities. These effects are cumulative in the double mutant F29W/ NHdel. On the other hand, maximal isometric tension development in Ca2+-activated reconstituted skinned fibers is not affected with F29W and NHdel, although the Ca2+ sensitivity of NHdel in this system is markedly reduced. We conclude that both mutations, NHdel and F29W, are functionally deleterious, possibly affecting interactions of the N domain with troponin I and/or T.

Overdenture as a restorative option for hypocalcified-hypoplastic amelogenesis imperfecta: a case report.

AIM: The aim of this report is to describe the restorative treatment of an 18-year-old patient diagnosed with autosomal recessive hypocalcified-hypoplastic amelogenesis imperfecta (AI). BACKGROUND: Esthetic and functional rehabilitations in AI cases are challenging and should consider individual aspects, such as age, socioeconomic status, AI type, and intraoral condition. REPORT: AI was diagnosed in an 18-year-old patient. SUMMARY: Considering the short length of crowns and roots, patient life expectancy, minimal invasiveness, amount of treatment time required, and lower costs, oral rehabilitation with overdentures provided an adequate functional and esthetic rehabilitation of the patient. CLINICAL SIGNIFICANCE: This report demonstrated overdentures to be a viable, relatively inexpensive, and non-invasive treatment choice of a patient with AI with concerns about treatment longevity, invasiveness, cost, esthetics, and long-term maintenance.

Study of antioxidant activity of non-conventional Brazilian fruits

This study aimed to analyze the proximate composition of seeds from some non-conventional Brazilian fruits, as well as to evaluate the antioxidant activity through DPPH • free radical and to quantify the total phenolic compounds. To obtain the extracts, dried and crushed seeds were extracted with ethanol for 30 min, in a ratio of 1:3 (seeds:ethyl alcohol), under continuous agitation, at room temperature. Then, the mixtures were filtered and the supernatants were subjected to rotary evaporator under pressure reduced to 40 °C. The results report that the seeds of non-conventional fruits are remarkable sources of lipids, and the extraction of oil from these seeds could be an alternative for the commercial utilization of waste. They also presented significant percentages of protein and carbohydrates. Ethanol extracts of seeds from non-conventional Brazilian fruits showed relevant antioxidant activity and high amount of phenolic compounds. Therefore Brazilian non-conventional fruits can be used as functional food products or feed. © 2011 Association of Food Scientists & Technologists (India).

Dermatoglyphics in sports sciences: Understanding the distribution of quantitative indicators in non-athletes and athletes of basketball according to their performance

Objectives. One of the concerns of Sports Sciences is the search for methodologies that can help discover potential athletes. In this sense, some initiatives have been taken in an attempt to identify and characterize the genetic profile of dermatoglyphic marks (fingerprints). The present work has the objective of understanding the distribution of quantitative dermatoglyphic indicators in basketball players with different levels of performance compared to non-players. Methods. The subjects observed constituted 125 individuals, divided into five numerically equal groups, three of which were composed of professional basketball players according to their level of participation (Brazilian Team, National Championship and São Paulo Championship) and the last two formed by weekend players and non-players, respectively. Eleven dermatoglyphic variables were analysed in the descriptive level by means of measurement of position, variability and limits of confidence of the median, and, in inferential terms, the Kruskal-Wallis statistical test was adopted. Results. The more expressive ones were: TRC, counting lines a-b and A'-d, behave differently between athletes and non-athletes. Conclusion. Studies about this kind of analysis should be continued, calling on resources that take into consideration all variables simultaneously as a multivariate study. © 2012 Revista Andaluza de Medicina del Deporte.

Functional nanostructured catalysts based on the niobates to the dry methane reforming and ethylene homologation reactions

Catalytic activity and selectivity of niobate-based nanostructured materials were investigated. Dry methane reforming (DMR) and ethylene homologation reaction (EHR) were selected as test reactions. KSr 2Nb5O15, Sr2NaNb5O 15 and NaSr2(NiNb4)O15 δ niobate powders were prepared by the high energy ball milling method and calcined in a reductor atmosphere. N2 adsorption isotherms, X-ray diffraction and infrared spectroscopy characterization was performed. Hydrogen pretreated niobates showed from low to moderate catalytic initial activity in DMR's test, nevertheless the materials were deactivated rapidly and the kinetic parameters associated to deactivation were estimated. Otherwise, non-treated catalysts showed a high initial activity in EHR's test and KSr2Nb 5O15 catalyst requires 24 h to the total deactivation with a high selectivity to form propylene. A reaction mechanism to the propylene formation is discussed. © 2012 Elsevier Ltd. All rights reserved.

Biochemical, functional, structural and phylogenetic studies on Intercro, a new isoform phospholipase A2 from Crotalus durissus terrificus snake venom

Crotoxin is a neurotoxin from Crotalus durissus terrificus venom that shows immunomodulatory, anti-inflammatory, antimicrobial, antitumor and analgesic activities. Structurally, this toxin is a heterodimeric complex composed by a toxic basic PLA2 (Crotoxin B or CB) non-covalently linked to an atoxic non-enzymatic and acidic component (Crotapotin, Crotoxin A or CA). Several CA and CB isoforms have been isolated and characterized, showing that the crotoxin venom fraction is, in fact, a mixture of different molecules derived from the combination of distinct subunit isoforms. Intercro (IC) is a protein from the same snake venom which presents high similarity in primary structure to CB, indicating that it could be an another isoform of this toxin. In this work, we compare IC to the crotoxin complex (CA/CB) and/or CB in order to understand its functional aspects. The experiments with IC revealed that it is a new toxin with different biological activities from CB, keeping its catalytic activity but presenting low myotoxicity and absence of neurotoxic activity. The results also indicated that IC is structurally similar to CB isoforms, but probably it is not able to form a neurotoxic active complex with crotoxin A as observed for CB. Moreover, structural and phylogenetic data suggest that IC is a new toxin with possible toxic effects not related to the typical CB neurotoxin. © 2013.

Involvement of pituitary gonadotropins, gonadal steroids and breeding season in sex change of protogynous dusky grouper, Epinephelus marginatus (Teleostei: Serranidae), induced by a non-steroidal aromatase inhibitor

Two experiments were performed using the aromatase inhibitor (AI) letrozole (100mg/kg) to promote sex change, from female-to-male, in protogynous dusky grouper. One experiment was performed during the breeding season (spring) and the other at the end of the breeding season (summer). During the spring, AI promoted sex change after 9weeks and the sperm produced was able to fertilize grouper oocytes. During the summer, the sex change was incomplete; intersex individuals were present and sperm was not released by any of the animals. Sex changed gonads had a lamellar architecture; cysts of spermatocytes and spermatozoa in the lumen of the germinal compartment. In the spring, after 4weeks, 11ketotestosterone (11KT) levels were higher in the AI than in control fish, and after 9weeks, coincident with semen release, testosterone levels increased in the AI group, while 11KT returned to the initial levels. Estradiol (E2) levels remained unchanged during the experimental period. Instead of decreasing throughout the period, as in control group, 17 α-OH progesterone levels did not change in the AI-treated fish, resulting in higher values after 9weeks when compared with control fish. fshβ and lhβ gene expression in the AI animals were lower compared with control fish after 9weeks. The use of AI was effective to obtain functional males during the breeding season. The increase in androgens, modulated by gonadotropins, triggered the sex change, enabling the development of male germ cells, whereas a decrease in E2 levels was not required to change sex in dusky grouper. © 2013 Elsevier Inc.

Can overharvesting of a non-timber-forest-product change the regeneration dynamics of a tropical rainforest? The case study of Euterpe edulis

The exploitation of non-timber forest products is often considered a low-impact activity in tropical forests. However, assessments of the impacts of such activity are mostly focused on the harvested species and not on the plant community, thus limiting our understanding for establishing forest management recommendations. We investigated the consequences of Euterpe edulis palm heart harvesting on the seed rain in the Brazilian Atlantic rainforest. We compared the density of E. edulis individuals, as well as the density of E. edulis seeds, and the density, richness and functional composition of seed rain of the whole plant community, before and after palm heart harvesting in a 10 ha permanent plot. This assessment was carried out in preserved (typical old-growth Atlantic rainforest) and in disturbed (more open habitat dominated by the native bamboo Guadua tagoara) forest patches. Palm harvesting reduced the E. edulis population from 202.16 to 25.67 ind/ha and its seed rain density from 0.362 to 0.3 seeds/m2 and from 2.395 to 0.15 seeds/m2 in preserved and disturbed forest patches, respectively. Seed density of light-dependent climbers, pioneer trees, bamboo and animal-dispersed seeds increased after palm harvesting, especially in the disturbed forest patches, where palm harvesting was more intense and may have changed the light regime of the understory. On the other hand, species richness of the plant community declined by half. We observed a remarkable decline in the number of animal-dispersed species, especially for those with large seeds, suggesting that the activity of seed dispersers, including many species attracted by E. edulis fruits, was reduced. Therefore, harvesting of E. edulis palm heart may change the regeneration dynamics of the Atlantic rainforest, both due to shifts in forest structure, mediated by the removal of individuals from the forest canopy, and in community functioning, mediated by the interference on the activity of seed dispersers. © 2013 Elsevier B.V. All rights reserved.

Fast assembly of non-thiolated DNA on gold surface at lower pH

In a typical protocol for attaching DNA to a gold electrode, thiolated DNA is incubated with the electrode at neutral pH overnight. Here we report fast adsorption of non-thiolated DNA oligomers on gold electrodes at acidic pH (i.e., pH ~3.0). The peak-to-peak potential difference and the redox peak currents in typical cyclic voltammetry of [Fe(CN)6]3- are investigated to monitor the attachment. Compared with incubation at neutral pH, the lower pH can significantly promote the adsorption processes, enabling efficient adsorption even in 30min. The adsorption rate is DNA concentration-dependent, while the ionic strength shows no influence. Moreover, the adsorption is base-discriminative, with a preferred order of A>C≫G, T, which is attributed to the protonation of A and C at low pH and their higher binding affinity to gold surface. The immobilized DNA is functional and can hybridize with its complementary DNA but not a random DNA. This work is promising to provide a useful time-saving strategy for DNA assembly on gold electrodes, allowing fast fabrication of DNA-based biosensors and devices. © 2013 Elsevier Inc.

As relações concessivas no português falado sob a perspectiva da gramática discursivo-funcional

Pós-graduação em Estudos Linguísticos - IBILCE