Representation and analysis of control surface freeplay nonlinearity

Different representations for a control surface freeplay nonlinearity in a three degree of freedom aeroelastic system are assessed. These are the discontinuous, polynomial and hyperbolic tangent representations. The Duhamel formulation is used to model the aerodynamic loads. Assessment of the validity of these representations is performed through comparison with previous experimental observations. The results show that the instability and nonlinear response characteristics are accurately predicted when using the discontinuous and hyperbolic tangent representations. On the other hand, the polynomial representation fails to predict chaotic motions observed in the experiments. (c) 2012 Elsevier Ltd. All rights reserved.

TOWARDS NEW BOTANICAL PESTICIDES: THE TOXIC EFFECT OF Eremanthus goyazensis (Asteraceae) LEAVES ESSENTIAL OIL AGAINST Brevipalpus phoenicis (Acari: Tenuipalpidae)

This work reports the chemical characterization of Eremanthus goyzensis essential oil and its toxic effect over Brevipalpus phoenicis. The essential oil displayed a major composition of sesquiterpenes (61.87%) including trans-caryophillene (26.81%) and germacrene-D (13.31%). The fumigation test indicated a promising bioactivity over adult B. phoenicis individuals at 24 h (2.03 mu L/L of air) and 48 h (1.08 mu L/L of air) of exposition. A brief discussion of essential oils composition and their singular role on the toxic effect over B. phoenicis is provided here. Our results may contribute to a new and profitable use of a species of Brazilian flora on agribusiness.

Essential Oil and other Constituents from Magnolia ovata Fruit

The volatile and non-volatile constituents of the unripe fruits of Magnolia ovata (A. St.-Hil.) Spreng. (Magnoliaceae) were studied. The essential oils were obtained by hydrodistillation of the fruit of two plant populations (A and B) and analyzed by GC/FID and GC/MS. The oil of sample A was rich in sesquiterpenes, mainly spathulenol (19.3%), while the oil of sample B showed a predominance of aliphatic compounds, mainly hexadecanoic acid (52.0%). Extracts of the dried fruit contained fourteen known compounds including nine lignoids (magnovatin A, magnovatin B, acuminatin, licarin A, oleiferin A, oleiferin C, kadsurenin M, 4-O-demethylkadsurenim M and 7-epi-virolin), two sesquiterpene lactones (parthenolide and michelenolide) and three alkaloids (lysicamine, lanuginosine and O-methylmoschatoline). Michelenolide, 7-epi-virolin and lisycamine are reported for the first time in the species, while the remaining compounds have already been reported in the leaves and/or trunk bark of Magnolia ovata. Acetylation of oleiferin A yielded a new compound, acetyl oleiferin A, whose NMR data and that of michelenolide are furnished.

Electrophysiological Responses of the Naupactus bipes Beetle to Essential Oils from Piperaceae Species

Electrophysiological responses based on electroantennographic detection (GC-EAD) and electroantennography (EAG) analysis of Naupactus bipes beetles (Germar, 1824) (Coleoptera: Curculionidae: Brachycerinae) were used to test volatile oils of Piper gaudichaudianum, P. regnellii and P. hispidum. In the EAG experiments, female and male beetles showed significant EAG response to the three volatile oils of Piper species, with the females' responses slightly higher than the males'. The experiments with GC-EAD revealed that some terpenoids (namely, alpha-pinene, beta-pinene, myrcene, alpha-copaene and germacrene) present in the leaf essential oils of the Piper species are perceptible to female and male beetles.

Is the food frequency consumption essential as covariate to estimate usual intake of episodically consumed foods?

BACKGROUNDS/OBJECTIVES: The aim of this paper is to verify the performance of the frequency of consumption as variable for prediction of the usual intakes of foods. SUBJECTS/METHODS: In total, 725 individuals who answered two nonconsecutive 24-h recall and one food frequency questionnaire (FFQ) in the 'Healthy Survey-Sao Paulo-Brazil'. An additional indicator variable indicating if one is usual consumer was created before analyzing. The Multiple Source Method and National Cancer Institute method were used to estimate usual intake of selected food considering different models of prediction: with no covariates; with FFQ; with FFQ plus indicator variable; and with only indicator variable. RESULTS: For foods that are consumed every day or almost every day, the inclusion of the FFQ and/or the indicator variable as covariates resulted in similar percentiles of consumption when compared with the model with no covariates. For episodically consumed foods, the models with FFQ plus indicator variable and with only indicator variable estimated similar percentiles of intake. CONCLUSIONS: The use of the indicator variable instead the FFQ appears as a good alternative to estimate usual intake of episodically consumed foods.

Effect of Solvent-Induced Coil to Helix Conformational Change on the Two-Photon Absorption Spectrum of Poly(3,6-phenanthrene)

This paper investigates the effect of solvent-induced conformational changes of poly(3,6-phenanthrene) on their two-photon absorption (2PA). Such effect was studied employing the wavelength-tunable femtosecond Z-scan technique and modeled using the sum-over-essential states approach. We observed a strong reduction of the 2PA cross-section when the sample was prepared in hexane (poor solvent) in comparison to chloroform (good solvent), which is related to the conformation adopted by the polymer in each case. In chloroform it adopts a random coil conformation, as opposed to the one-handed helix conformation in hexane. Our results pointed out that the coil to helix conformation change decreases the degree of molecular planarity of the polymer pi-conjugated backbone, which is primarily responsible for their optical nonlinearity, contributing to diminishing the effective transition dipole moments and, consequently, the 2PA cross-section. Moreover, by studying the nonlinear response with different light polarization, we showed that, although the solvent-induced conformational change does not alter the molecular symmetry of the polymer, it modifies considerably the direction of the transition dipole moments between the excited states.

IN VITRO TRYPANOCIDAL EVALUATION OF PINANE DERIVATIVES FROM ESSENTIAL OILS OF RIPE FRUITS FROM Schinus terebinthifolius RADDI (ANACARDIACEAE)

Essential oils of ripe fruits from Schinus terebinthifolius (Anacardiaceae), obtained using a pilot extractor and a Clevenger apparatus were chemically characterized. Due the high amount of (-)-alpha-pinene in both oils, this monoterpene was tested against the protozoan parasite Trypanosoma cruzi, showing a moderate potential (IC50 63.56 mu g/mL) when compared to benznidazole (IC50 43.14 mu g/mL). Otherwise, (-)-alpha-pinene oxide did not showed anti-trypanosomal activity (IC50 > 400 mu g/mL) while (-)-pinane showed an IC50 of 56.50 mu g/mL. The obtained results indicated that the epoxydation of a-pinene results to the loss of the anti-parasitic activity while its hydrogenation product, contributed slightly to the increased activity.

Antimicrobial Activity of Essential Oils against Streptococcus mutans and their Antiproliferative Effects

This study aimed to evaluate the activity of essential oils (EOs) against Streptococcus mutans biofilm by chemically characterizing their fractions responsible for biological and antiproliferative activity. Twenty EO were obtained by hydrodistillation and submitted to the antimicrobial assay (minimum inhibitory (MIC) and bactericidal (MBC) concentrations) against S. mutans UA159. Thin-layer chromatography and gas chromatography/mass spectrometry were used for phytochemical analyses. EOs were selected according to predetermined criteria and fractionated using dry column; the resulting fractions were assessed by MIC and MBC, selected as active fractions, and evaluated against S. mutans biofilm. Biofilms formed were examined using scanning electron microscopy. Selected EOs and their selected active fractions were evaluated for their antiproliferative activity against keratinocytes and seven human tumor cell lines. MIC and MBC values obtained for EO and their active fractions showed strong antimicrobial activity. Chemical analyses mainly showed the presence of terpenes. The selected active fractions inhibited S. mutans biofilm formation (P < 0.05) did not affect glycolytic pH drop and were inactive against keratinocytes, normal cell line. In conclusion, EO showed activity at low concentrations, and their selected active fractions were also effective against biofilm formed by S. mutans and human tumor cell lines.

Leucine Is Essential for Attenuating Fetal Growth Restriction Caused by a Protein-Restricted Diet in Rats

Certain amino acids, such as leucine (Leu) are not only substrates for protein synthesis but also are important regulators of protein metabolism. Moreover, it is known that alterations in intrauterine growth favor the development of chronic diseases in adulthood. Therefore, we investigated the role of Leu in combination with other BCAA on effects that are induced by maternal protein restriction on fetal growth. Wistar rats were divided into 4 groups according to the diet provided during pregnancy: control (C; 20% casein); V+I [5% casein + 2% L-valine (Val) + 2% L-isoleucine (Ile)1; KYT 15% casein + 1.8% L-lysine (Lys) + 1.2% L-tyrosine (Tyr) + 1% L-threonine (Thr)1; and BCAA (5% casein + 1.8% L-Leu + 1.2% L-Val + 1% L-Ile). Maternal protein restriction reduced the growth and organ weight of the offspring of dams receiving the V+I and KYT diets compared with the C group. Supplementation with BCAA reversed this growth deficit, minimizing the difference or restoring the mass of organs and carcass fat, the liver and muscle protein, and the RNA concentrations compared with newborns in the C group (P < 0.05). These effects could be explained by the activation of the mTOR signaling pathway, because phosphorylation of 4E-BP1 in the liver of offspring of the BCAA group was greater than that in the C, V+I, and KYT groups. The present results identify a critical role for Leu in association with other BCAA in the activation of the mTOR signaling pathway for the control of altered intrauterine growth induced by a maternal low-protein diet. J. Nutr. 142: 924-930, 2012.

NUTRITIONAL BALANCE, ESSENTIAL OIL AND WOOD PRODUCTION FROM Corymbia citriodora Hill & Johnson WITH SEWAGE SLUDGE AND MINERAL FERTILIZER APPLICATIONS

The Corymbia citriodora is one of the most important forest species in Brazil and the reason is the diversity of its use, because it produces good quality wood and the leaves may be used for essential oil production. Although, there are not many studies about species and the handling effect in the nutritional balance. This study aimed to evaluate the biomass production and nutrient balance in the conventional production of essential oil and wood of Corymbia citriodora with sewage sludge application. The experiment design established was the randomized blocks, with four replicates and two treatments: 1 - fertilization with 10 tons ha(-1) (dry mass) of sewage sludge, supplemented with K and B, and 2 - mineral fertilization. It was evaluated the aerial biomass production, the nutrient export of the leaves, the essential oil and wood production at four years old. The trees that received application of sewage sludge produced 20 % more leaves biomass than the trees with mineral fertilization, resulting in larger oil production. Besides, the trees with sewage sludge application produced 14.2 tons ha(-1) yr(-1) of woody biomass that was 27 % higher than the treatment with mineral fertilization. For both treatments the N balance was negative, but treatment with sewage sludge application (-45 kg ha(-1)) was four times lower than the observed on mineral fertilization treatment (-185 kg ha(-1)). It may be concluded in this paper that the application of sewage sludge benefits the production of leaves biomass, essential oil and wood, besides result better nutritional balance of the Corymbia citriodora production system.

Deregulation of apoptosis-related genes is associated with PRV1 overexpression and JAK2 V617F allele burden in Essential Thrombocythemia and Myelofibrosis

Background: Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF) are Chronic Myeloproliferative Neoplasms (MPN) characterized by clonal myeloproliferation/myeloaccumulation without cell maturation impairment. The JAK2 V617F mutation and PRV1 gene overexpression may contribute to MPN physiopathology. We hypothesized that deregulation of the apoptotic machinery may also play a role in the pathogenesis of ET and PMF. In this study we evaluated the apoptosis-related gene and protein expression of BCL2 family members in bone marrow CD34(+) hematopoietic stem cells (HSC) and peripheral blood leukocytes from ET and PMF patients. We also tested whether the gene expression results were correlated with JAK2 V617F allele burden percentage, PRV1 overexpression, and clinical and laboratory parameters. Results: By real time PCR assay, we observed that A1, MCL1, BIK and BID, as well as A1, BCLW and BAK gene expression were increased in ET and PMF CD34(+) cells respectively, while pro-apoptotic BAX and anti-apoptotic BCL2 mRNA levels were found to be lower in ET and PMF CD34(+) cells respectively, in relation to controls. In patients' leukocytes, we detected an upregulation of anti-apoptotic genes A1, BCL2, BCL-XL and BCLW. In contrast, pro-apoptotic BID and BIMEL expression were downregulated in ET leukocytes. Increased BCL-XL protein expression in PMF leukocytes and decreased BID protein expression in ET leukocytes were observed by Western Blot. In ET leukocytes, we found a correlation between JAK2 V617F allele burden and BAX, BIK and BAD gene expression and between A1, BAX and BIK and PRV1 gene expression. A negative correlation between PRV1 gene expression and platelet count was observed, as well as a positive correlation between PRV1 gene expression and splenomegaly. Conclusions: Our results suggest the participation of intrinsic apoptosis pathway in the MPN physiopathology. In addition, PRV1 and JAK2 V617F allele burden were linked to deregulation of the apoptotic machinery.

Evaluation of the Concentration of Nonessential and Essential Elements in Chicken, Pork, and Beef Samples Produced in Brazil

Food safety is a global concern. Meat represents the most important protein source for humans. Thus, contamination of meat products by nonessential elements is a ready source of human exposure. In addition, knowledge of the concentration of essential elements is also relevant with respect to human nutrition. The aim of the present study was to determine the concentration of 17 elements in pork, beef, and chicken produced in Brazil. Meat samples were analyzed by inductively coupled plasma mass spectrometry. The estimated daily intake for nonessential elements including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and antimony (Sb) through meat consumption is below the toxicological reference values. However, high levels were detected for the nonessential element cesium (Cs), mainly in beef samples, an observation that deserves future studies to identify the source of contamination and potential adverse consequences.

Anatomy and essential oils from aerial organs in three species of Aldama (Asteraceae-Heliantheae) that have a difficult delimitation

Recently, molecular analysis caused the South American Viguiera Kunth species to be transferred to Aldama La Llave. However, the circumscription has not been established for certain of the South American species, including Aldama filifolia (Sch. Bip. ex Baker) E. E. Schill. & Panero, A. linearifolia (Chodat) E. E. Schill. & Panero and A. trichophylla (Dusen) Magenta (comb. nov.), which had previously been treated as synonyms because of their high similarity. Therefore, the present study aimed to evaluate the anatomy of the aerial organs, and the yield and chemical composition of the essential oils from these three species, to determine the differences among them and thereby assist in species distinction. The anatomical analysis identified characteristics unique to each species, which are primarily related to the position and occurrence of secretory structures. Histochemical analysis demonstrated that the glandular trichomes and the canals secrete lipophilic substances, which are characterised by the presence of essential oils. The analysis of these essential oils identified monoterpenes as their major constituent and allowed for the recognition of chemical markers for each species. The anatomical and chemical characteristics identified by the present study confirmed that the studied samples belong to three distinct taxa.

Modeling and identification of freeplay nonlinearity

A nonlinear analysis is performed for the purpose of identification of the pitch freeplay nonlinearity and its effect on the type of bifurcation of a two degree-of-freedom aeroelastic system. The databases for the identification are generated from experimental investigations of a pitch-plunge rigid airfoil supported by a nonlinear torsional spring. Experimental data and linear analysis are performed to validate the parameters of the linearized equations. Based on the periodic responses of the experimental data which included the flutter frequency and its third harmonics, the freeplay nonlinearity is approximated by a polynomial expansion up to the third order. This representation allows us to use the normal form of the Hopf bifurcation to characterize the type of instability. Based on numerical integrations, the coefficients of the polynomial expansion representing the freeplay nonlinearity are identified. Published by Elsevier Ltd.

Fractionation of lemon essential oil by solvent extraction: Phase equilibrium for model systems at T=298.2 K

The fractioning of lemon essential oil can be performed by liquid-liquid extraction using hydrous ethanol as a solvent. A quaternary mixture composed of limonene, gamma-terpinene, beta-pinene, and citral was used to simulate lemon essential oil. In this paper, we present (liquid + liquid) equilibrium data that were experimentally determined for systems containing essential oil compounds, ethanol, and water at T = 298.2 K. The experimental data were correlated using the NRTL and UNIQUAC models, and the mean deviations between calculated and experimental data were less than 0.0053 in all systems, indicating the accuracy of these molecular models in describing our systems. The results show that as the water content in the solvent phase increased, the values of the distribution coefficients decreased, regardless of the type of compound studied. However, the oxygenated compound always showed the highest distribution coefficient among the components of the essential oil, thus making deterpenation of the lemon essential oil a feasible process. (C) 2012 Elsevier Ltd. All rights reserved.