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Major recent advances. Structured self-assembled liquids have been considered as efficient microreactors for organic and enzymatic reactions. Only recently scientists learned to use food-grade cosolvents and coemulsifiers together with hydrophilic non-ionic surfactants and to construct U-type phase diagrams with large isotropic regions ranging continuously from the oil-rich corner to the water-rich corner without any phase separation. The U-type microemulsions facilitate triggering and control of certain reactions by changing water activities. Maillard thermal degradation between sugars and amino acids is the main, and almost the only. chemical reaction that has been studied in food-grade microemulsions. Some examples of recent studies include: Maillard processes in binary structured fluids composed of monoglycerides of fatty acids and water forming microemulsions and lyotropic liquid crystalline structures; pseudoternary and pseudoquaternary W/O microemulsions; U-type microemulsions (W/O, O/W and bicontinuous microemulsions); enzymatic reactions aimed to prepare other surfactants such as sugar esters, monoglycerides and lysolecithins or triglycerides. Reactions in microreactors lead to unique new products. The reaction products and rates are controlled by the hydrophilicity/lipophilicity of the reagents (guest molecules), their molar ratios, type of oil phase, nature of surfactants and oil/surfactant ratios, nature of curvature and its elasticity (adjusted by cosolvent and coemulsifier) and by the water activity. The field is in its infancy and will need work of many more model reactions before it will be used in industrial food applications. Enzymatic reactions in non-food microemulsions are common practice but only few examples of food microemulsions as enzymatic microreactors have been extensively studied. (C) 2003 Elsevier Science Ltd. All rights reserved.

The microstructure of an unusual Winsor IV isotropic region of five-component microemulsions based on nonionic surfactants was studied. The microemulsions are composed of R(+)-limonene, water, propylene glycol (PG), ethanol (EtOH), and polyoxyethylene sorbitan monostearate (Tween 60) with a 1:1:3 R(+)limonene/ethanol/surfactant weight ratio. The phase diagrams of the system are characterized by an extended single continuous isotropic region starting from an oil-rich solution containing no aqueous phase (reverse micelles) to the water/propylene glycol (1/1) corner (swollen direct micelles). The microemulsions seem to be attractive for food applications. The microstructure changes gradually, smoothly, and continuously upon increasing the aqueous phase content. The microemulsion transforms from a water-in-oil (W/O) microemulsion to a bicontinuous phase and to an oil-in-water (O/W) microemulsion. The microstructure of the microemulsion along a selected dilution line, is probed using pulsed gradient spin-echo NMR, conductivity, and viscosity. The results are compared with a corresponding non-food-grade system based on C18:1E10 (Brij 96v). The hydrodynamic radius (R-H) of O/W microemulsion samples based on Brij 96v and Tween 60, at 90% aqueous phase, was determined to be 5.4 +/- 0.2 and 5.2 +/- 0.2 nm, respectively, and the calculated values of the area of the polar headgroup (a) are 87 for Brij 96v and 160 Angstrom(2) for Tween 60-based microemulsions. The ratio of the water self-diffusion coefficient, D-W, to the PG self-diffusion coefficient (D-PG) (termed the L ratio)was found to be sensitive to the aqueous phase content. In the O/W microemulsions, the water/PG mixture diffuses as hydrogen bonded entity (molecular diffusion controlled), while in the W/O microemulsions, the PG partitions, in part, at the interface and the dominate diffusion process is neither aggregate nor molecular controlled.

Osmotic shock is a familiar means for rupturing viral capsids and exposing their genomes intact. The necessary conditions for providing this shock involve incubation in high-concentration salt solutions, and lower permeability of the capsids to salt ions than to water molecules. We discuss here how values of the capsid strength can be inferred from calculations of the osmotic pressure differences associated with measured values of the critical concentration of incubation solution.

Analysis of the phenolic constituents of shea (Vitellaria paradoxa) kernels by LC-MS revealed eight catechin compounds-gallic acid, catechin, epicatechin, epicatechin gallate, gallocatechin, epigallocatechin, gallocatechin gallate, and epigallocatechin gallate-as well as quercetin and trans-cinnamic acid. The mean kernel content of the eight catechin compounds was 4000 ppm (0.4% of kernel dry weight), with a 2100-9500 ppm range. Comparison of the profiles of the six major catechins from 40 Vitellaria provenances from 10 African countries showed that the relative proportions of these compounds varied from region to region. Gallic acid was the major phenolic compound, comprising an average of 27% of the measured total phenols and exceeding 70% in some populations. Colorimetric analysis (101 samples) of total polyphenols extracted from shea butter into hexane gave an average of 97 ppm, with the values for different provenances varying between 62 and 135 ppm of total polyphenols.

Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phylosterols, cholesterol-lowering agents, in food products is of great interest to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12 times more than the dissolution capacity of the oil [R-(+)-limonene] for the same compounds. The solubilization capacity of phylosterols and cholesterol along a dilution line in a pseudo-ternary phase diagram [on this dilution line the weight ratio of R-(+)-limonene/ethanol/Tween 60 is constant at 1:1:3] was correlated to the microstructure transitions along the dilution line. Structural aspects were studied by self-diffusion NMR spectroscopy. The ability of phytosterols to compete with cholesterol for penetration into bile salt micelles in the gut may be limited to rich aqueous systems (O/W microemulsion).

Various industries including food and pharmaceuticals are sharing increasing interest in microemulsions. Also, one can demonstrate that solubilization of active materials within the core or interface of microemulsions may have environmental benefits. In this work. we report three examples of new microemulsion formulations specially designed to be capable of solubilizing active materials and protecting the environment from the emission of hazardous matter or protecting sensitive molecules from the detrimental effects of the environment. In the first example, fire-resistant ingredients were incorporated in hydraulic fluids based on water-in-oil (W/O) microemulsions and their typical characteristics were described. In the second example, five-component oil-in-water (O/W) microemulsions were designed to solubilize lycopene and protect it from exposure to light. In the third example, a friendly solvent (butyl lactate) was microemulsified to form nanosized liquid droplets capable of solubilizing bromine-based bactericide formulations of sophisticated wood preservatives. The new vehicles exhibit a very significant solubilization capacity and can be applied in aqueous media. In the last example, the active matter may be triggered when demanded and the release will be followed by film formation. (C) 2003 Published by Elsevier B.V.

Lutein, a naturally occurring carotenoid, is widely distributed in fruits and vegetables and is particularly concentrated in the Tagetes erecta flower. Epidemiological studies suggest that a high lutein intake (6 mg/day) increases serum levels that are associated with a lower risk of cataract and age-related macular degeneration. Lutein can either be free or esterified (myristate, palmitate, or stearate). Both are practically insoluble in aqueous systems, and their solubility in food grade solvents (oils) is very limited, resulting is low bioavailability. To improve its solubility and bioavailability, lutein was solubilized in U-type food grade microemulsions based on ethoxylated sorbitan fatty acid esters, glycerol, R-(+)-limonene, and ethanol. Some of the main findings are as follows: (1) reverse micellar and W/O compositions solubilized both luteins better than an O/W microemulsion, and maximum solubilization is obtained within the bicontinuous phase; (2) free lutein is solubilized better than the esterified one, in the W/O microemulsions, whereas the esterified lutein is better accommodated within the O/W microemulsion; (3) vegetable oils decrease the solubilization of free lutein; (4) glycerol and alcohol enhance the solubilization of both luteins; (5) solubilization is surfactant-dependent in all mesophase structures, but its strongest effect is in the bicontinuous phase.

On the basis of our combined clinical experience in treating patients with panic disorder (PD) using the Mastery of Anxiety and Panic therapist guide (Craske, Barlow, & Meadows, 2000) and in supervising others in its use, we felt that there were additional issues to consider that could assist therapists conducting CBT for PD. We divide the paper into 6 sections: general principles, psychoeducation, cognitive restructuring, interoceptive exposure, situational exposure, and consolidating treatment gains/termination. We hope that these clinically practical strategies facilitate the dissemination of this effective treatment.

We examine treatment exclusion and refusal rates as well as reasons for non-participation in a sub-sample of phone interviews conducted to determine eligibility for a randomized study of treatments for generalized social phobia (GSP). This study compared group comprehensive cognitive behavioral therapy (CCBT) to fluoxetine (FLU), placebo (PLA), or their combination. Results suggest that the major exclusion for the study was due to comorbid depression, followed by having a different diagnosis as primary. Patient refusal to enter the study was also common, with the most frequently reported reason being not wanting to take medication. Notably, few people who refused stated an objection to entering CCBT or PLA. These results suggest that there is a need to develop and evaluate a treatment for social anxiety with comorbid depression and to systematically study reasons for reluctance to take medication among individuals with GSP.

Regularities of patterning in the Hebrew verb derivation system are adduced to support a new analysis of transitivity alternations that unifies causative & middle morphology. Verbs are constructed in the syntax from lexical roots & functional heads; the root, not the simple verb, provides the basic predicate & is merged with the light verb v as defined by Kenneth Hale & Samuel Jay Keyser (1993). Although v introduces the agent, a pair of agency heads are available to specify the thematic role of the external argument as cause vs agent of action & mark the verb morphologically with a causative vs intensive template; a second pair of functional heads provide voice morphology: the passive voice head applies to the fully constructed verb, whereas the middle voice head modifies the root & derives middle verbs independently from active verbs. 36 References. J. Hitchcock

Exposure and Response (ritual) Prevention (EX/RP) for obsessive-compulsive disorder (OCD) is a behaviorally based treatment that is the most effective treatment available for most patients with OCD. In this paper, [...]