CHARACTERIZATION OF AGROINDUSTRIAL SYSTEMS: A COMPARATIVE STUDY OF THE SUCRO-ENERGETIC SECTORS OF BRASIL AND COLOMBIA

Concern about the growing demand of food and fuel has focused the attention on countries with conditions to provide for global requirements. Also, the build-up of an environmental awareness has compelled several governments to implement programs for the addition of biofuels to oil derivatives. Considering their relevance as world and South American producers, this study makes a characterization of the sucro-energetic sectors of Brazil and Colombia, based on a view of agro-industrial systems, industrial organization and transaction cost economy. The approach followed considered of a secondary information survey and in-depth interviews. The main differences found are centered on institutional development level and production volumes. However, the use of the same raw material, sugarcane, trade opening policies, cultural approaches and regional integration, are factors that could generate links of commercial exchange and technological cooperation between the two countries.

Incorporation of antigenic GPI-proteins from Leishmania amazonensis to membrane mimetic systems: Influence of DPPC/cholesterol ratio

The reconstitution of membrane proteins into liposomes is a useful tool to prepare antigenic components that induce immunity. We have investigated the influence of the dipalmitoylphosphatidylcholine (DPPC)/cholesterol molar ratio on the incorporation of a GPI-protein from Leishmania amazonensis on liposomes and Langmuir monolayers. The latter system is a well behaved and practical model, for understanding the effect of variables such as surface composition and lipid packing on protein incorporation. We have found that the DPPC/cholesterol molar ratio significantly alters the incorporation of the GPI-protein. In the absence of cholesterol, reconstitution is more difficult and proteoliposomes cannot be prepared, which we correlated with disruption of the DPPC layer. Our results provide important information that Could be employed in the development of a vaccine system for this disease or be used to produce other GPI-systems for biotechnological application. (c) 2009 Elsevier Inc. All rights reserved.

Parity measurement of one- and two-electron double well systems

We outline a scheme to accomplish measurements of a solid state double well system (DWS) with both one and two electrons in nonlocalized bases. We show that, for a single particle, measuring the local charge distribution at the midpoint of a DWS using a SET as a sensitive electrometer amounts to performing a projective measurement in the parity (symmetric/antisymmetric) eigenbasis. For two-electrons in a DWS, a similar configuration of SET results in close-to-projective measurement in the singlet/triplet basis. We analyze the sensitivity of the scheme to asymmetry in the SET position for some experimentally relevant parameter, and show that it is experimentally realizable.

PHBHV/PCL microspheres as biodegradable drug delivery systems (DDS) for photodynamic therapy (PDT)

Unloaded microspheres were prepared from polyhydroxybutyrate-co-valerate (PHBHV) and poly(epsilon-caprolactone) (PCL) polymers using the emulsification-solvent evaporation method (EE). The study was conducted to determine the ideal polymeric composition and ideal molecular weight for the microspheres preparation to be used as a Drug Delivery System (DDS) for cancer therapy. In this work, NzPC, a new photosensitizer, has been investigated when incorporated into microspheres of PHBHV/PCL evaluating its application for Photodynamic Therapy (PDT) of neoplastic tissue. The biodegradation studies were conducted to analyze the effects of the incorporation of the NzPC and also to determine the release profiles in vitro condition. We also evaluated the dark toxicity and the photobiological effect of the PHBHV-PCL microspheres in cutaneous melanoma cell line (B-16-A1) used as a biological neoplastic medium.

Sol-gel preparation of near-infrared broadband emitting Er(3+)-doped SiO(2)-Ta(2)O(5) nanocomposite films

This article reports a study on the preparation, densification process, and structural and optical properties of SiO(2)-Ta(2)O(5) nanocomposite films obtained by the sol-gel process. The films were doped with Er(3+) and the Si:Ta molar ratio was 90:10. Values of refractive index, thickness and vibrational modes in terms of the number of layers and thermal annealing time are described for the films. The densification process is accompanied by OH group elimination, increase in the refractive index, and changes in film thickness. Full densification of the film is acquired after 90 min of annealing at 900 degrees C. The onset of crystallization and devitrification, with the growth of Ta(2)O(5) nanocrystals occurs with film densification, evidenced by high-resolution transmission electron microscopy. The Er(3+)-doped nanocomposite annealed at 900 degrees C consists of Ta(2)O(5) nanoparticles, with sizes around 2 nm, dispersed in the SiO(2) amorphous phase. The main emission peak of the film is detected at around 1532 nm, which can be assigned to the (4)I(13/2)->(4)I(15/2) transition of the Er(3+) ions present in the nanocomposites. This band has a full width at half medium of 64 nm, and the lifetime measured for the (4)I(13/2) levels is 5.4 ms, which is broader compared to those of other silicate systems. In conclusion, the films obtained in this work are excellent candidates for use as active planar waveguide. (C) 2010 Elsevier B.V. All rights reserved.

Interaction of 10-(octyloxy) decyl-2-(trimethylammonium) ethyl phosphate with mimetic membranes and cytotoxic effect on leukemic cells

10-(Octyloxy) decyl-2-(trimethylammonium) ethyl phosphate (ODPC) is an alkylphospholipid that can interact with cell membranes because of its amphiphilic character. We describe here the interaction of ODPC with liposomes and its toxicity to leukemic cells with an ED-50 of 5.4, 5.6 and 2.9 pM for 72 h of treatment for inhibition of proliferation of NB4, U937 and K562 cell lines, respectively, and lack of toxicity to normal hematopoietic progenitor cells at concentrations up to 25 pM. The ED-50 for the non-malignant HEK-293 and primary human umbilical vein endothelial cells (HUVEC) was 63.4 and 60.7 mu M, respectively. The critical micellar concentration (CMC) of ODPC was 200 mu M. Dynamic light scattering indicated that dipalmitoylphosphatidylcholine (DPPC) liposome size was affected only above the CMC of ODPC. Differential calorimetric scanning (DCS) of liposomes indicated a critical transition temperature (T(c)) of 41.5 degrees C and an enthalpy (Delta H) variation of 7.3 kcal mol(-1). The presence of 25 mu M ODPC decreased T(c) and Delta H to 393 degrees C and 4.7 kcal mol(-1), respectively. ODPC at 250 mu M destabilized the liposomes (36.3 degrees C. 0.46 kcal mol(-1)). Kinetics of 5(6)-carboxyfluorescein (CF) leakage from different liposome systems indicated that the rate and extent of CF release depended on liposome composition and ODPC concentration and that above the CMC it was instantaneous. Overall, the data indicate that ODPC acts on in vitro membrane systems and leukemia cell lines at concentrations below its CMC, suggesting that it does not act as a detergent and that this effect is dependent on membrane composition. (C) 2010 Elsevier B.V. All rights reserved.

Controllability of Volterra-Fredholm type systems in Banach spaces

We show the results in Chalishajar [Controllability of mixed Volterra-Fredholm-type integro-differential systems in Banach space, J. Franklin Inst. 344(1) (2007) 12-21] and Chang and Chalishajar [Controllability of mixed Volterra-Fredholm type integro-differential systems in Banach space, J. Franklin Inst., doi:10.1016/j. jfranklin.2008.02.002] are only valid for ordinary differential control systems. As a result the examples provided cannot be recovered as applications of the abstract results. (C) 2008 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

Approximate controllability of second-order distributed implicit functional systems

In this paper we study the approximate controllability of control systems with states and controls in Hilbert spaces, and described by a second-order semilinear abstract functional differential equation with infinite delay. Initially we establish a characterization for the approximate controllability of a second-order abstract linear system and, in the last section, we compare the approximate controllability of a semilinear abstract functional system with the approximate controllability of the associated linear system. (C) 2008 Elsevier Ltd. All rights reserved.

Interaction of adrenocorticotropin peptides with microheterogeneous systems - A fluorescence study

Adrenocorticotropin (ACM) and alpha-melanocyte stimulating hormone (alpha-MSH) are peptides which present many physiological effects related to pigmentation, motor and sexual behavior, learning and memory, analgesia, anti-inflammatory and antipyretic processes. The 13 amino acid residues of alpha-MSH are the same initial sequence of ACM and due to the presence of a tryptophan residue in position 9 of the peptide chain, fluorescence techniques could be used to investigate the conformational properties of the hormones in different environments and the mechanisms of interaction with biomimetic systems like sodium dodecyl sulphate (SDS) micelles, sodium dodecyl sulphate-poly(ethylene oxide) (SDS-PEO) aggregates and neutral polymeric micelles. In buffer solution, fluorescence parameters were typical of peptides containing tryptophan exposed to the aqueous medium and upon addition of surfactant and polymer molecules, the gradual change of those parameters demonstrated the interaction of the peptides with the microheterogeneous systems. From time-resolved experiments it was shown that the interaction proceeded with conformational changes in both peptides, and further information was obtained from quenching of Trp fluorescence by a family of N-alkylpyridinium ions, which possess affinity to the microheterogeneous systems dependent on the length of the alkyl chain. The quenching of Trp fluorescence was enhanced in the presence of charged micelles, compared to the buffer solution and the accessibility of the fluorophore to the quencher was dependent on the peptide and the alkylpyridinium: in ACTH(1-21) highest collisional constants were obtained using ethylpyridinium as quencher, indicating a location of the residue in the surface of the micelle, while in alpha-MSH the best quencher was hexylpyridinium, indicating insertion of the residue into the non-polar region of the micelles. The results had shown that the interaction between the peptides and the biomimetic systems where driven by combined electrostatic and hydrophobic effects: in ACTH(1-24) the electrostatic interaction between highly positively charged C-terminal and negatively charged surface of micelles; and aggregates predominates over hydrophobic interactions involving residues in the central region of the peptide; in alpha-MSH, which presents one residual positive charge, the hydrophobic interactions are relevant to position the Trp residue in the non-polar region of the microheterogeneous systems. (C) 2008 Elsevier B.V. All rights reserved.

Finite-temperature correlations and density profiles of an inhomogeneous interacting one-dimensional Bose gas

We calculate the density profiles and density correlation functions of the one-dimensional Bose gas in a harmonic trap, using the exact finite-temperature solutions for the uniform case, and applying a local density approximation. The results are valid for a trapping potential that is slowly varying relative to a correlation length. They allow a direct experimental test of the transition from the weak-coupling Gross-Pitaevskii regime to the strong-coupling, fermionic Tonks-Girardeau regime. We also calculate the average two-particle correlation which characterizes the bulk properties of the sample, and find that it can be well approximated by the value of the local pair correlation in the trap center.

The 2.0 angstrom crystal structure of a pocilloporin at pH 3.5: The structural basis for the linkage between color transition and halide binding

The pocilloporin Rtms5 and an engineered variant Rtms5(H146S) undergo distinct color transitions (from blue to red to yellow to colorless) in a pH-dependent manner. pK(a) values of 4.1 and 3.2 were determined for the blue (absorption lambda(max), 590 nm) to yellow (absorption lambda(max), similar to 453 nm) transitions of Rtms5 and Rtms5H(146). The pK(a) for the blue-yellow transition of Rtms5H(146S) increased by 1.4 U in the presence of 0.1 M KI, whereas the pK(a) for the same transition of Rtms5 was relatively insensitive to added halides. To understand the structural basis for these observations, we have determined to 2.0 A resolution the crystal structure of a yellow form of Rtms5(H146S) at pH 3.5 in the presence of iodide. Iodide was found occupying a pocket in the structure with a pH of 3.5, forming van der Waals contacts with the tyrosyl moiety of the chromophore. Elsewhere, it was determined that this pocket is occupied by a water molecule in the Rtms5(H141S) structure (pH 8.0) and by the side chain of histidine 146 in the wild-type Rtms5 structure. Collectively, our data provide an explanation for the observed linkage between color transitions for Rtms5(H146S) and binding to halides.

Lambda-fold 3-perfect 9-cycle systems

The spectrum for the decomposition of lambda K-v into 3-perfect 9-cycles is found for all lambda > 1. (The case lambda = 1 was dealt with in an earlier paper by the authors and Lindner.) The necessary conditions for the existence of a suitable decomposition turn out to be sufficient.

Measurements of adipocity and high blood pressure among children and adolescents living in Belo Horizonte

Objective: To verify an association, if it exists, between obesity and blood pressure raised beyond the 90th percentile in children and adolescents, and to determine the measure of adiposity that best correlates with blood pressure in these subjects. Design: Cross-sectional study. Setting: A school-based study in Belo Horizonte, Brazil. Participants: We selected randomly 1,403 students, aged from 6 to 18 years, from 545,046 students attending 521 public and private schools. Those selected completed the study. Main measures of outcome: We recorded the weight, height, skin fold in the triceps, subscapular, and suprailiac areas, waist and hip circumference, body-mass index, and resting systolic and diastolic blood pressures using a mercury sphygmomanometer. Results: In univariate analyses, body mass index greater or lesser than 85th percentile, measurements of skin thickness in the subscapular and suprailiac areas, and the sum of all measurements of skinfold thickness, were associated with both systolic and diastolic measurements of blood pressure. After multivariate analyses that adjusted for all measurements of adiposity except itself, and age, race, and socioeconomic state, we found that the increased body mass index was associated with a 3.6-fold increased frequency of elevated systolic measurements of blood pressure, with 9596 confidence intervals from 2.2 to 5.8, and a 2.7-fold increased frequency of elevated measurements of diastolic blood pressure, with 95% confidence intervals from 1.9 to 4.0. Conclusions: Body-mass index serves as a better predictor of elevated blood pressure among children than do local measurements of adiposity.

Sequential Changes of Longitudinal and Radial Myocardial Deformation Indices in the Healthy Neonate Heart

Background: Significant hemodynamic changes, including preload and afterload modifications, occur during the transition from the fetal to the neonatal environment. The ductus arteriosus closes, pulmonary vascular resistance decreases, and pulmonary blood flow increases. Strain rate (SR) and strain (e) have been proposed as ultrasound indices for quantifying regional wall deformation. This study was designed to determine if these indices can detect variations in regional deformation between early and late neonatal periods. Methods: Data were obtained from 30 healthy neonates (15 male). The initial study was performed at a mean age of 20.1614 hours (exam 1) and the second at 31.962.9 days (exam 2). Apical and parasternal views were used to quantify regional left ventricular (LV) and right ventricular (RV) longitudinal and radial SR and e, and systolic, early, and late diastolic values were calculated from these curves. A paired-samples t test was performed comparing the two groups. Results: Compared with exam 1, LV radial deformation showed significant reductions in peak systolic e in the basal and mid segments (51615% vs 4669%, P < .01). LV longitudinal deformation behaved similarly, showing significant peak systolic e reductions in all measured segments. Systolic SR showed reductions only in the basal and apical segments of the lateral wall and in the mid portion of the inferior wall (-1.9 +/- 0.5 vs -1.7 +/- 0.3 s(-1) and -1.9 +/- 0.4 vs -1.7 +/- 0.2 s(-1), respectively, P = .03). RV longitudinal free and inferior wall systolic SR and e values were significantly higher in exam 2. Conclusions: LV peak systolic e decreases in exam 2 were possibly due to afterload increase and preload decrease. The lower RV initial deformation indices could be attributed to increased afterload caused by physiologic pulmonary hypertension or immature RV contractile properties. SR seemed to be a more robust index than e and less influenced by preload and afterload hemodynamic alteration. (J Am Soc Echocardiogr 2010;23:294-300.)

Concomitant expression of epithelial-mesenchymal transition biomarkers in breast ductal carcinoma: Association with progression

Epithelial to mesenchymal transition (EMT) is a process implicated in cancer progression in which the underlying cellular changes have been identified mainly using in vitro models. We determined the expression of some putative EMT biomarkers including E-cadherin, beta-catenin, zinc finger factor Snail (Snail), transforming growth factor beta 1 (TGF beta 1), TGF beta type II receptor (TBRII) and the HGF receptor (c-met) and their possible correlation to progression and overall survival in a series of breast ductal carcinoma in situ (DCIS) and invasive ductal carcinomas (IDC). Biomarkers were immunohistochemically determined in 55 IDC specimens from which 21 had lymph node metastases and in 95 DCIS specimens, 46 of these cases associated to invasive carcinoma, in a tissue microarray (TMA). Positive cytoplasmic staining of TGF beta 1 (78.2%), c-met (43.6%), Snail (34.5%), TBRII (100%), membranous E-cadherin (74.5%) and membranous/cytoplasmic beta-catenin (71%) were detected in the IDC samples. Metastatic lymph node samples displayed similar frequencies. A significant increase of c-met and TGF beta 1 positivity along DCIS to IDC progression was noted but only TGF beta 1 positivity was associated with presence of lymph node metastases and advanced stages in IDC. The evaluation of the other EMT markers in DCIS did not show differences in positivity rate as compared to invasive carcinomas. DCIS either pure or associated to IDC showed similar expression of the analyzed biomarkers. All the carcinomas exhibited positive expression of TBRII. Associations between the markers, determined by Spearman`s correlation coefficient, showed a significant association between TGF beta 1 and respectively E-cadherin, beta-catenin and cmet in DCIS cases, but in invasive carcinomas only cadherin and catenin were positively correlated. Kaplan-Meier survival curves revealed that none of the EMT biomarkers analyzed were correlated with survival, which was significantly determined only by clinical and hormone receptor parameters.