Oleogels from Glycerol‐Based Lyotropic Liquid Crystals: Phase Diagrams and Structural Characterization

In the course of our studies on structured reverse lyotropic liquid crystals (LLC) as oleogels, a system was designed with the desired physical and rheology properties for cosmetic and pharmaceutical applications. The aqueous phase was partially replaced by glycerol to minimize bacteriological problems and obtain specific rheology characteristics. The constructed phase diagrams are based on ternary mixtures of glycerol monooleate (GMO), decane, water, and glycerol. The main lyotropic mesophase obtained in this study was reverse hexagonal derived from dilution line 8:2 (72 wt% GMO and 18 wt% decane) and 10 wt% water; or water:glycerol (wt ratios 3:1 and 1:1) mixture. It was found that heat‐cool fluctuation caused formation of new pseudo‐equilibrium structures with mesomorphic transformations to more fluid and less ordered mesostructures. Replacing up to 50 wt% of the water by glycerol significantly increases the gel phase region in the phase diagram, meaning more structural compositional options. The structural parameters were determined using cross‐polarized light microscopy (CPLM), differential scanning calorimeter (DSC), powder X‐ray diffraction (PXRD), and small angle X‐ray scattering (SAXS). Rheological measurements revealed viscoelastic properties of lyotropic liquid crystals with a decrease in the elasticity (G′), plasticity (G″), and complex viscosity (η*), as a function of increasing the glycerol content.     

Associative Grammar Combination Operators for Tree-Based Grammars

Polarized unification grammar (PUG) is a linguistic formalism which uses polarities to better control the way grammar fragments interact. The grammar combination operation of PUG was conjectured to be associative. We show that PUG grammar combination is not associative, and even attaching polarities to objects does not make it order-independent. Moreover, we prove that no non-trivial polarity system exists for which grammar combination is associative. We then redefine the grammar combination operator, moving to the powerset domain, in a way that guarantees associativity. The method we propose is general and is applicable to a variety of tree-based grammar formalisms.     

Evidence for nonlinear binding of PAHs to dissolved humic acids

Binding of pyrene, fluoranthene, and phenanthrene to dissolved humic acids (HA) was determined by the fluorescence quenching (FQ) and complexation-flocculation (CF) methods. Determinations by the CF method, using varying contaminant concentrations and a constant HA concentration, yielded nonlinear Freundlich-type isotherms (n = 0.65-0.84). Experiments using both the CF and the FQ methods with varying HA concentrations and a constant contaminant concentration yielded curved "Stern-Volmer"-type plots that also indicate nonlinear binding. These findings suggest that linear partitioning or site complexation in the presence of excess available sites cannot fully describe the interactions of hydrophobic compounds with dissolved humic material. Site-specific hydrophobic interactions at limited interior or external molecular surfaces may be considered.     

On the Effective Deployment of Functional Formal Verification

We examine IBM's exploitation of formal verification using RuleBase—a formal verification tool developed by the IBM Haifa Research Laboratory. The goal of the paper is methodological. We identify an integrated methodology for the deployment of formal verification which involves three complementary modes: architectural verification, block-level verification, and design exploration.     

A Human-Robot Collaborative Reinforcement Learning Algorithm

This paper presents a new reinforcement learning algorithm that enables collaborative learning between a robot and a human. The algorithm which is based on the Q(λ) approach expedites the learning process by taking advantage of human intelligence and expertise. The algorithm denoted as CQ(λ) provides the robot with self awareness to adaptively switch its collaboration level from autonomous (self performing, the robot decides which actions to take, according to its learning function) to semi-autonomous (a human advisor guides the robot and the robot combines this knowledge into its learning function). This awareness is represented by a self test of its learning performance. The approach of variable autonomy is demonstrated and evaluated using a fixed-arm robot for finding the optimal shaking policy to empty the contents of a plastic bag. A comparison between the CQ(λ) and the traditional Q(λ)-reinforcement learning algorithm, resulted in faster convergence for the CQ(λ) collaborative reinforcement learning algorithm.     

Gauging of Cytochrome c Structural Fluctuation by Time-Resolved Proton Pulse

A brief proton pulse technique, based on photo-excitation of pyranine, was employed for measuring the protonation dynamics of cytochrome c in aqueous solutions. Time-resolved monitoring of the protonation state of the pyranine anion yielded detailed information from which the temporal state protonation of the surface carboxylates and histidine residues were deduced. The surface groups were found to be coupled by electrostatic interaction where the state of protonation of one affects the pK of the others. In the same sense, altering the charge distribution of a protein by a redox reaction affects the reactivity of the surface groups with protons in the bulk. The surface groups can exchange protons among themselves at a very high rate. The velocities of these reactions are functions of the connectivity between the proton binding sites. A single proton exchange reaction between the surface groups could be identified as the proton exchange between H26 and E44. The reaction is fast and affected by the redox state of the protein. It is proposed that the enhanced rate of this reaction is coupled with transient conformational changes that are not noticeable in time-averaging measurements such as X-ray diffraction or NMR.     

Diurnal patterns of micropollutants concentrations in domestic greywater

In recent years, much interest has been given to presence of micropollutants in municipal wastewater, some of which are suspected to be endocrine disruptors, toxic or carcinogenic. Much less attention has been paid to their presence in greywater. The present research studies the diurnal patterns of micropollutants in greywater and computes their daily loads. Monitoring was carried-out using auto-controlled sampling system, designed to overcome the erratic greywater generation. Two main generation periods were identified: morning (5:00–11:00) and evening-night (18:00–2:00), contributing about 20% and >50% of daily greywater discharge, respectively. Average specific daily greywater discharge was 57 L p^?1d^?1, which matches reported value for greywater generated by showers and washbasins in Israel. The most frequently detected micropollutants in this study were methylparben (preservative), galaxolide (fragrance) and oxybenzone (UV-filter), which are common ingredients in many personal care-products. Their daily loads were 2, 840, 1, 887 and 728 µg p^?1d^?1, respectively.     

Marital distress and mental health care service utilization.

Objective: This study was designed to evaluate the association between marital distress and mental health service utilization in a population-based sample of men and women (N = 1,601). Method: The association between marital distress and mental health care service utilization was evaluated for overall mental health service utilization and for specific sectors of treatment providers, including psychiatrist, other mental health provider, other medical provider, and religious services provider. Interviews were used to assess past-year service utilization and presence of anxiety, mood, and substance use disorders. Results: Approximately 12% of married individuals sought help for problems with their emotions, nerves, or substance use during the 12 months preceding the interview. Marital distress was significantly associated with (a) overall mental health service utilization and service utilization provided by each of the sectors of providers when controlling for demographic variables and (b) overall mental health service utilization and receiving treatment from a psychiatrist when additionally controlling for past-year anxiety, mood, or substance use disorders. There was little evidence that the associations between marital distress and service utilization were moderated by gender or presence of psychiatric disorders. Conclusion: The finding that marital distress is associated with greater mental health care service utilization suggests that clinicians should assess both individual and relationship factors among individuals presenting for treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory-phonetic projection and lexical structure in the recognition of sine-wave words.

Speech remains intelligible despite the elimination of canonical acoustic correlates of phonemes from the spectrum. A portion of this perceptual flexibility can be attributed to modulation sensitivity in the auditory-to-phonetic projection, although signal-independent properties of lexical neighborhoods also affect intelligibility in utterances composed of words. Three tests were conducted to estimate the effects of exposure to natural and sine-wave samples of speech in this kind of perceptual versatility. First, sine-wave versions of the easy and hard word sets were created, modeled on the speech samples of a single talker. The performance difference in recognition of easy and hard words was used to index the perceptual reliance on signal-independent properties of lexical contrasts. Second, several kinds of exposure produced familiarity with an aspect of sine-wave speech: (a) sine-wave sentences modeled on the same talker; (b) sine-wave sentences modeled on a different talker, to create familiarity with a sine-wave carrier; and (c) natural sentences spoken by the same talker, to create familiarity with the idiolect expressed in the sine-wave words. Recognition performance with both easy and hard sine-wave words improved after exposure only to sine-wave sentences modeled on the same talker. Third, a control test showed that signal-independent uncertainty is a plausible cause of differences in recognition of easy and hard sine-wave words. The conditions of beneficial exposure reveal the specificity of attention underlying versatility in speech perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Disparities in arteriovenous fistula placement in older hemodialysis patients

The benefits of an arteriovenous fistula (AVF) as the preferred vascular access for hemodialysis have been clearly demonstrated. However, only about 20% of patients in the United States initiate hemodialysis with an AVF. In this study, we assessed whether disparities exist in the type of first hemodialysis access placed prior to dialysis start (rather than that used at dialysis initiation), to detect whether certain disadvantaged groups might have lower likelihood of AVF placement. Study cohort of 118,767 incident hemodialysis patients ≥67 years of age (1/2005–12/2008) derived from the United States Renal Data System was linked with Medicare claims data to identify the type of initial access placed predialysis. We used logistic regression model with outcome being the initial predialysis placement of an AVF as opposed to an arteriovenous graft or a central venous catheter. Increasing age, female sex, black race, lower body mass index, urban location, certain comorbidities, and shorter pre–end‐stage renal disease nephrology care are all associated with a significantly lower likelihood of AVF placement as initial access predialysis. Our study suggests the presence of significant disparities in the placement of an AVF as initial hemodialysis vascular access. We suggest that additional attention should be paid to these patient groups to improve disparities by patient education, earlier referral, and close follow‐up.