Organizational maintenance repair parts and special tools list : power unit, utility pack, gas turbine engine driven (Airesearch model PPU85-5), non-winterized, FSN 6115-937-0929, (Airesearch model PPU85-4), winterized, FSN 6115-134-0825.

"April 1969."

Operator and organizational maintenance manual : power unit, utility pack, gas turbine engine driven (Airesearch model PPU85-5), non-winterized, FSN 6115-937-0929 (Airesearch model PPU85-4), winterized, FSN 6115-134-0825.

"December 1968."

Immuno-potentiating activity of surfactant vesicles in DNA and subunit vaccination

Enhanced immune responses for DNA and subunit vaccines potentiated by surfactant vesicle based delivery systems outlined in the present study, provides proof of principle for the beneficial aspects of vesicle mediated vaccination. The dehydration-rehydration technique was used to entrap plasmid DNA or subunit antigens into lipid-based (liposomes) or non-ionic surfactant-based (niosomes) dehydration-rehydration vesicles (DRV). Using this procedure, it was shown that both these types of antigens can be effectively entrapped in DRV liposomes and DRV niosomes. The vesicle size of DRV niosomes was shown to be twice the diameter (~2µm) of that of their liposome counterparts. Incorporation of cryoprotectants such as sucrose in the DRV procedure resulted in reduced vesicle sizes while retaining high DNA incorporation efficiency (~95%). Transfection studies in COS 7 cells demonstrated that the choice of cationic lipid, the helper lipid, and the method of preparation, all influenced transfection efficiency indicating a strong interdependency of these factors. This phenomenon has been further reinforced when 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE): cholesteryl 3b- [N-(N’ ,N’ -dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol)/DNA complexes were supplemented with non-ionic surfactants. Morphological analysis of these complexes using transmission electron microscopy and environmental scanning electron microscopy (ESEM) revealed the presence of heterogeneous structures which may be essential for an efficient transfection in addition to the fusogenic properties of DOPE. In vivo evaluation of these DNA incorporated vesicle systems in BALB/c mice showed weak antibody and cell-mediated immune (CMI) responses. Subsequent mock challenge with hepatitis B antigen demonstrated that, 1-monopalmitoyl glycerol (MP) based DRV, is a more promising DNA vaccine adjuvant. Studying these DRV systems as adjuvants for the Hepatitis B subunit antigen (HBsAg) revealed a balanced antibody/CMI response profile on the basis of the HBsAg specific antibody and cytokine responses which were higher than unadjuvated antigen. The effect of addition of MP, cholesterol and trehalose 6,6’-dibehenate (TDB) on the stability and immuno-efficacy of dimethyldioctadecylammonium bromide (DDA) vesicles was investigated. Differential scanning calorimetry showed a reduction in transition temperature of DDA vesicles by ~12°C when incorporated with surfactants. ESEM of MP based DRV system indicated an increased vesicle stability upon incorporation of antigen. Adjuvant activity of these systems tested in C57BL/6j mice against three subunit antigens i.e., mycobacterial fusion protein- Ag85B-ESAT-6, and two malarial antigens - merozoite surface protein-1, (MSP1), and glutamate rich protein, (GLURP) revealed that while MP and DDA based systems induced comparable antibody responses, DDA based systems induced powerful CMI responses.

Surfactant vesicle-mediated delivery of DNA vaccines via the subcutaneous route

Compared to naked DNA immunisation, entrapment of plasmid-based DNA vaccines into liposomes by the dehydration-rehydration method has shown to enhance both humoural and cell-mediated immune responses to encoded antigens administered by a variety of routes. In this paper we have compared the potency of lipid-based and non-ionic surfactant based vesicle carrier systems for DNA vaccines after subcutaneous immunisation. Plasmid pI.18Sfi/NP containing the nucleoprotein (NP) gene of A/Sichuan/2/87 (H3N2) influenza virus in the pI.18 expression vector was incorporated by the dehydration-rehydration method into various vesicle formulations. The DRV method, entailing mixing of small unilamellar vesicles (SUV) with DNA, followed by dehydration and rehydration, yielded high DNA vaccine incorporation values (85-97% of the DNA used) in all formulations. Studies on vesicle size revealed lipid-based systems formed cationic submicron size vesicles whilst constructs containing a non-ionic surfactant had significantly large z-average diameters (>1500 nm). Subcutaneous vesicle-mediated DNA immunisation employing two DRV(DNA) formulations as well as naked DNA revealed that humoural responses (immunoglobulin total IgG, and subclasses IgG 1 and 1gG 2a) engendered by the plasmid encoded nucleoprotein were substantially higher after dosing twice, 28 days apart with 10 μg DRV-entrapped DNA compared to naked DNA. Comparison between the lipid and non-ionic based vesicle formulations revealed no significant difference in stimulated antibody production. These results suggest that, not only can DNA be effectively entrapped within a range of lipid and non-ionic based vesicle formulations using the DRV method but that such DRV vesicles containing DNA may be a useful system for subcutaneous delivery of DNA vaccines. © 2004 Elsevier B.V. All rights reserved.

Recuperação e purificação do antígeno 503 de Leishmania i. chagasi expresso em E. coli e remoção de endotoxina utilizando adsorção em leito expandido

The growing interest and applications of biotechnology products have increased the development of new processes for recovery and purification of proteins. The expanded bed adsorption (EBA) has emerged as a promising technique for this purpose. It combines into one operation the steps of clarification, concentration and purification of the target molecule. Hence, the method reduces the time and the cost of operation. In this context, this thesis aim was to evaluate the recovery and purification of 503 antigen of Leishmania i. chagasi expressed in E. coli M15 and endotoxin removal by EBA. In the first step of this study, batch experiments were carried out using two experimental designs to define the optimal adsorption and elution conditions of 503 antigen onto Streamline chelating resin. For adsorption assays, using expanded bed, it was used a column of 2.6 cm in diameter by 30.0 cm in height coupled to a peristaltic pump. In the second step of study, the removal of endotoxin during antigen recovery process was evaluated employing the non-ionic surfactant Triton X-114 in the washing step ALE. In the third step, we sought developing a mathematical model able to predict the 503 antigen breakthrough curves in expanded mode. The experimental design results to adsorption showed the pH 8.0 and the NaCl concentration of 2.4 M as the optimum adsorption condition. In the second design, the only significant factor for elution was the concentration of imidazole, which was taken at 600 mM. The adsorption isotherm of the 503 antigen showed a good fit to the Langmuir model (R = 0.98) and values for qmax (maximum adsorption capacity) and Kd (equilibrium constant) estimated were 1.95 mg/g and 0.34 mg/mL, respectively. Purification tests directly from unclarified feedstock showed a recovery of 59.2% of the target protein and a purification factor of 6.0. The addition of the non-ionic surfactant Triton X-114 to the washing step of EBA led to high levels (> 99%) of LPS removal initially present in the samples for all conditions tested. The mathematical model obtained to describe the 503 antigen breakthrough curves in Streamline Chelanting resin in expanded mode showed a good fit for both parameter estimation and validation steps. The validated model was used to optimize the efficiencies, achieving maximum values of the process and of the column efficiencies of 89.2% and 75.9%, respectively. Therefore, EBA is an efficient alternative for the recovery of the target protein and removal of endotoxin from an E. coli unclarified feedstock in just one step.

New Method for the Estimation of Viscosity of Pure and Mixtures of Ionic Liquids Based on the UNIFAC–VISCO Model

A modified UNIFAC–VISCO group contribution method was developed for the correlation and prediction of viscosity of ionic liquids as a function of temperature at 0.1 MPa. In this original approach, cations and anions were regarded as peculiar molecular groups. The significance of this approach comes from the ability to calculate the viscosity of mixtures of ionic liquids as well as pure ionic liquids. Binary interaction parameters for selected cations and anions were determined by fitting the experimental viscosity data available in literature for selected ionic liquids. The temperature dependence on the viscosity of the cations and anions were fitted to a Vogel–Fulcher–Tamman behavior. Binary interaction parameters and VFT type fitting parameters were then used to determine the viscosity of pure and mixtures of ionic liquids with different combinations of cations and anions to ensure the validity of the prediction method. Consequently, the viscosities of binary ionic liquid mixtures were then calculated by using this prediction method. In this work, the viscosity data of pure ionic liquids and of binary mixtures of ionic liquids are successfully calculated from 293.15 K to 363.15 K at 0.1 MPa. All calculated viscosity data showed excellent agreement with experimental data with a relative absolute average deviation lower than 1.7%.

Avaliação por SAXS e DSC das interações entre H2O e Renex-100

The aggregation behavior of the non-ionic surfactant Renex-100 in aqueous solutions and mesophases was evaluated by SAXS in a wide range of concentrations, between 20 and 30 °C. Complementary, water interactions were defined by DSC curves around 0°C. SAXS showed that the system undergoes the following phase transitions, from diluted to concentrated aqueous solutions: 1) isotropic solution of Renex aggregates; 2) hexagonal mesophase; 3) lamellar mesophase; and 4) isotropic solution. DSC analysis indicated the presence of interfacial water above 70wt%, which agreed with the segregation of free water to form the structural mesophases observed by SAXS bellow this concentration.

Extração no ponto nuvem de compostos orgânicos homólogos e isômeros

In this work, the feasibility of employing micelle-mediated extraction for selective separation of homologous or isomeric organic compounds is demonstrated. Firstly, the main parameters controlling extraction performances, such as surfactant concentration and temperature were varied. A Scheffé-type experimental design was demonstrated as a novel and useful method to characterize the various experimental factors. At each point selected in the two-phase domain and for a given solute, extraction percentage (E%), concentration ratio, phase volume ratio, and equilibrium partition coefficient (K C) were determined. The values of E% and K C decrease in the following order: phenol > 1-phenylethanol ~ 2-phenylethanol > benzyl alcohol.

Avaliação por SAXS e DSC das interações entre H2O e Renex-100

The aggregation behavior of the non-ionic surfactant Renex-100 in aqueous solutions and mesophases was evaluated by SAXS in a wide range of concentrations, between 20 and 30 °C. Complementary, water interactions were defined by DSC curves around 0°C. SAXS showed that the system undergoes the following phase transitions, from diluted to concentrated aqueous solutions: 1) isotropic solution of Renex aggregates; 2) hexagonal mesophase; 3) lamellar mesophase; and 4) isotropic solution. DSC analysis indicated the presence of interfacial water above 70wt%, which agreed with the segregation of free water to form the structural mesophases observed by SAXS bellow this concentration.

Improving diquat efficacy on grasses by adding adjuvants to the spray solution before use

The effect of five adjuvants (non-ionic surfactant, paraffinic oil, vegetable oil, mixture of fatty acids methyl esters plus surfactant blend, and organosilicone) on diquat efficacy was assessed on poverty brome, sterile oat, and Italian ryegrass in field and pot experiments. All tank mixtures with diquat increased diquat efficacy from 50-54% to 77-98% as for fresh weight reduction, indicating significant enhancement of diquat efficacy on grasses. The increased efficacy was most likely attributed to better droplet retention and diffusion on the leaf surfaces. When combined with non-ionic surfactant, diquat showed slightly more rapid control of grass weeds (i.e. symptoms were visible within a few hours after application).

Synthesis of isomaltooligosaccharides and oligodextrans in a recycle membrane bioreactor by the combined use of dextransucrase and dextranase

A recycle ultrafiltration membrane reactor was used to develop a continuous synthesis process for the production of isomaltooligosaccharides (IMO) from sucrose, using the enzymes dextransucrase and dextranase. A variety of membranes were tested and the parameters affecting reactor stability, productivity, and product molecular weight distribution were investigated. Enzyme inactivation in the reactor was reduced with the use of a non-ionic surfactant but its use had severe adverse effects on the membrane pore size and porosity. During continuous isomaltooligosaccharide synthesis, dextransucrase inactivation was shown to occur as a result of the dextranase activity and it was dependent mainly on the substrate availability in the reactor and the hydrolytic activity of dextranase. Substrate and dextranase concentrations (50-200 mg/mL(-1) and 10-30 U/mL(-1), respectively) affected permeate fluxes, reactor productivity, and product average molecular weight. The oligodextrans and isomaltooligosaccharides formed had molecular weights lower than in batch synthesis reactions but they largely consisted of oligosaccharides with a degree of polymerization (DP) greater than 5, depending on the synthesis conditions. No significant rejection of the sugars formed was shown by the membranes and permeate flux was dependent on tangential flow velocity. (C) 2004 Wiley Periodicals, Inc.

Recovery of astaxanthin using colloidal gas aphrons (CGA): a mechanistic study

The aim of this study is to investigate the mechanism responsible for the recovery of astaxanthin using Colloidal Gas Aphrons (CGA), which are surfactant stabilised microbubbles. The latter were produced using different surfactant solutions (Cetyl Trimethyl Ammonium Bromide (CTAB)-cationic, Sodium Dodecyl Sulfate (SDS)-anionic, TWEEN 60-non-ionic and mixtures of TWEEN 60-SPAN 80- non-ionic with varying hydrophobicity) at stirring speed 8000 rpm and stirring time 5 min. Experiments were carried out at varying pH and volumetric ratios of astaxanthin to CGA, and with two different astaxanthin standard suspensions: (i) astaxanthin dispersed in aqueous solutions and (ii) astaxanthin dispersed in ethanolic/aqueous solutions with different compositions of ethanol (20/80 (v/v) and 40/60 (v/v)). When astaxanthin is dispersed in aqueous solutions the separation seems to occur mainly by electrostatic interactions. Therefore the recoveries are higher in the case of the cationic surfactant when astaxanthin particles are strongly negatively charged, as shown by the zeta potential measurements. When ethanol is present, highest recoveries are achieved with CGA produced from the non-ionic surfactant, which indicates that, under these conditions, separation is driven mainly by hydrophobic interactions. In experiments with ethanolic/aqueous suspensions, when the hydrophobicity of the surfactant was increased by increasing volumes of SPAN 80, the CGA produced were less stable; thus higher recoveries of astaxanthin under conditions that favour hydrophobic interactions were not observed. (C) 2008 Elsevier B.V All rights reserved.

Puroindoline-a, a lipid binding protein from common wheat, spontaneously forms prolate protein micelles in solution

The self-assembly in solution of puroindoline-a (Pin-a), an amphiphilic lipid binding protein from common wheat, was investigated by small angle neutron scattering, dynamic light scattering and size exclusion chromatography. Pin-a was found to form monodisperse prolate ellipsoidal micelles with a major axial radius of 112 +/- 4.5 A ˚ and minor axial radius of 40.4 +/- 0.18 A ˚ . These protein micelles were formed by the spontaneous self-assembly of 38 Pin-a molecules in solution and were stable over a wide pH range (3.5–11) and at elevated temperatures (20–65 degC). Pin-a micelles could be disrupted upon addition of the non-ionic surfactant dodecyl-b-maltoside, suggesting that the protein self-assembly is driven by hydrophobic forces, consisting of intermolecular interactions between Trp residues located within a well-defined Trp-rich domain of Pin-a.

Electrochemical study of o-toluidine blue impregnated in mesoporous silica channels

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Synthesis and characterization of mesoporous TiO2 nanostructured films prepared by a modified sol-gel method for application in dye solar cells

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