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Protein adsorption at liquid–liquidinterfaces is of immenserelevance to many biological processes and dairy-based functionalfoods. Due to experimental limitations, however, there is still aremarkable lack of understanding of the adsorption mechanism, particularlyat a molecular level. In this study, atomistic molecular dynamicssimulations were used to elucidate the approach and adsorption mechanismof β-lactoglobulin (β-LG) at a decane–water interface.Through multiple independent simulations starting from three representativeinitial orientations of β-LG relative to the decane surfacethe rate at which β-LG approaches the oil/water interface isfound to be independent of its initial orientation, and largely stochasticin nature. While the residues that first make contact with the decaneand the final orientation of β-LG upon adsorption are similarin all cases, the adsorption process is driven predominantly by structuralrearrangements that preserve the secondary structure but expose hydrophobicresidues to the decane surface. This detailed characterization ofthe adsorption of β-LG at an oil/water interface should informthe design and development of novel encapsulation and delivery systemsin the food and pharmaceutical sciences. [ABSTRACT FROM AUTHOR]

Nucleation of calcium carbonate was achieved on mixed octadecanoic acid/octadecanol Langmuir monolayers. Two different nucleation regimes are distinguished based on monolayer alcohol content corresponding to the zone axes [01.0] (high alcohol content, weak or no interaction between the critical calcium carbonate nucleus and the monolayer) and [11̅.0] (low alcohol content, stronger face selective nucleation). The cation-mediated hydrogen-bonded soap network is disrupted by the presence of the alcohol, resulting in a reduced interaction between the monolayer and the subphase. This leads to little or no control over the nucleating crystal. The alcohol concentration at which the transition between the two preferential zone axes occurs is weakly dependent on growth pressure. No other variation with growth pressure was observed. [ABSTRACT FROM AUTHOR]

Aerosol OT/water exhibits a lamellar phase over a wide range of concentrations. We show, by magnetic resonance (NMR) and scanning electron microscopy (SEM), that the morphology of the lamellar phase varies significantly across that range and that the rate of equilibration depends strongly on concentration (25, 33, and 50 wt %) with, paradoxically, the faster equilibration at higher surfactant concentrations. We find that the 25 wt % sample exhibits a defect-rich local structure, characteristic of a superposed L3character. Further into the lamellar region, at 33 wt %, this defect-rich structure persists heterogeneously, while, at 50 wt %, the lamellar phase domains are highly ordered. The NMR methods used here included 2H spectroscopy and the two-dimensional NMR method, diffusion−diffusion exchange spectroscopy (DEXSY). The latter was used to obtain quantitative information on the domain sizes and defects within the polydomain lamellar mesophase. Comparison of the NMR with the SEM results suggests that, at 25 wt % AOT, bilayer defects play an important role in influencing the 2H NMR and DEXSY NMR results. [ABSTRACT FROM AUTHOR]

Traditional models of human memory have postulated the need for a brief phonological or verbatim representation of verbal input as a necessary gateway to a higher level conceptual representation of the input. Potter has argued that meaningful sentences may be encoded directly in a conceptual short-term memory (CSTM) running parallel in time to such a phonological store. The primary aim of the current study was to evaluate two main tenets of the CSTM model: that linguistic context biases selection of information entering the conceptual store, and that information not integrated into a coherent structure is rapidly forgotten. Results confirmed these predictions for spoken sentences heard by both young and older adults, supporting the generality of the model and suggesting that CSTM remains stable in normal aging. [ABSTRACT FROM AUTHOR]

MRI is under evaluation for image-guided intervention for prostate cancer. The sensitivity and specificity of MRI parameters is determined via correlation with the gold-standard of histopathology. Whole-mount histopathology of prostatectomy specimens can be digitally registered to in vivo imaging for correlation. When biomechanical-based deformable registration is employed to account for deformation during histopathology processing, the ex vivo biomechanical properties are required. However, these properties are altered by pathology fixation, and vary with disease. Hence, this study employs magnetic resonance elastography (MRE) to measure ex vivo prostate biomechanical properties before and after fixation. A quasi-static MRE method was employed to measure high resolution maps of Young’s modulus (E) before and after fixation of canine prostate and prostatectomy specimens (n  =  4) from prostate cancer patients who had previously received radiation therapy. For comparison, T1, T2 and apparent diffusion coefficient (ADC) were measured in parallel. E (kPa) varied across clinical anatomy and for histopathology-identified tumor: peripheral zone: 99(±22), central gland: 48(±37), tumor: 85(±53), and increased consistently with fixation (factor of 11  ±  5; p  <  0.02). T2 decreased consistently with fixation, while changes in T1 and ADC were more complex and inconsistent. The biomechanics of the clinical prostate specimens varied greatly with fixation, and to a lesser extent with disease and anatomy. The data obtained will improve the precision of prostate pathology correlation, leading to more accurate disease detection and targeting. [ABSTRACT FROM AUTHOR]

Biomechanical model based deformable image registration has been widely used to account for prostate deformation in various medical imaging procedures. Biomechanical material properties are important components of a biomechanical model. In this study, the effect of incorporating tumor-specific material properties in the prostate biomechanical model was investigated to provide insight into the potential impact of material heterogeneity on the prostate deformation calculations. First, a simple spherical prostate and tumor model was used to analytically describe the deformations and demonstrate the fundamental effect of changes in the tumor volume and stiffness in the modeled deformation. Next, using a clinical prostate model, a parametric approach was used to describe the variations in the heterogeneous prostate model by changing tumor volume, stiffness, and location, to show the differences in the modeled deformation between heterogeneous and homogeneous prostate models. Finally, five clinical prostatectomy examples were used in separately performed homogeneous and heterogeneous biomechanical model based registrations to describe the deformations between 3D reconstructed histopathology images and ex vivo magnetic resonance imaging, and examine the potential clinical impact of modeling biomechanical heterogeneity of the prostate. The analytical formulation showed that increasing the tumor volume and stiffness could significantly increase the impact of the heterogeneous prostate model in the calculated displacement differences compared to the homogeneous model. The parametric approach using a single prostate model indicated up to 4.8 mm of displacement difference at the tumor boundary compared to a homogeneous model. Such differences in the deformation of the prostate could be potentially clinically significant given the voxel size of the ex vivo MR images (0.3  ×  0.3  ×  0.3 mm). However, no significant changes in the registration accuracy were observed using heterogeneous models for the limited number of clinical prostatectomy patients modeled and evaluated in this study. [ABSTRACT FROM AUTHOR]

High school is an important time in the educational career of students. It is also a time when adolescents face many behavioral, academic, and social-emotional challenges. Current statistics about the behavioral, academic, and social-emotional challenges faced by adolescents, and the impact on society through incarceration and dropout, have prompted high schools to direct their attention toward keeping students engaged and reducing high-risk behavioral challenges. The purpose of the study was to examine the effects of School-Wide Positive Behavioral Interventions and Supports (SW-PBIS) on the levels of individual student problem behaviors during a 3-year effectiveness trial without random assignment to condition. Participants were 36,653 students in 12 high schools. Eight schools implemented SW-PBIS, and four schools served as comparison schools. Results of a multilevel latent growth model showed statistically significant decreases in student office discipline referrals in SW-PBIS schools, with increases in comparison schools, when controlling for enrollment and percent of students receiving free or reduced price meals. In addition, as fidelity of implementation increased, office discipline referrals significantly decreased. Results are discussed in terms of effective- ness of a SW-PBIS approach in high schools and considerations to enhance fidelity of implementation. [ABSTRACT FROM AUTHOR]