The psychology of psychiatric genetics: Evidence that positive emotions in females moderate genetic sensitivity to social stress associated with the BDNF Val??Met polymorphism.

Previous work indicated protective effects of positive emotions on genetically influenced stress sensitivity. Given the fact that expression of brain-derived-neurotrophic-factor (BDNF) is associated with stress-induced behavioral changes, it was hypothesized that the BDNF Val??Met genotype may mediate genetic effects on stress sensitivity, conditional on the level of concurrent positive emotions. Subjects (n = 446) participated in a momentary assessment study, collecting appraisals of stress and affect in the flow of daily life. Multilevel regression analyses examined moderation of daily life stress-induced negative affect (NA) by BDNF genotype, and to what degree this was conditional on concurrent positive emotions. Results showed that heterozygous BDNF "Met" carriers exhibited an increased NA response to social stress compared with "Val/Val" subjects. Positive emotions at the time of the stressor decreased BDNF genetic moderation of the NA response to social stress in a dose-response fashion. This effect was most pronounced in BDNF Met carriers. Thus, the impact of BDNF genotype on stress sensitivity is conditional on the experience of positive emotions. Interdisciplinary research in psychology and psychiatric genetics may lead to the improvement of treatment choices in stress-related disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On‐line monitoring of chord distributions in liquid–liquid dispersions and suspension polymerizations by using the focused beam reflectance measurement technique

The on‐line monitoring of the droplet/particle size distributions is very important to ensure the quality and applicability of various products in heterogeneous systems. For this reason, the main objective of the present work was to study the usage of the focused beam reflectance measurement (FBRM) technique for monitoring of liquid–liquid dispersions (styrene dispersion in aqueous solutions) and suspension polymerization of styrene. To do better understand the FBRM technique in these systems, the effects of surfactant concentrations, agitation speed and ambient light were evaluated during the in‐line monitoring of average chord lengths and chord‐length distributions (CLD) at different operation conditions in batch experiments. In addition, a preliminary investigation of the optimal probe position was conducted in the polymerization experiments. It is shown that the FBRM technique is sensitive to variations of particle sizes in the characteristic ranges of particle diameters of typical styrene suspension polymerizations, being useful for monitoring and also control applications that require the on‐line characterization of CLD in real time in liquid–liquid dispersions and polymerization systems. POLYM. ENG. SCI., 56:309–318, 2016. © 2015 Society of Plastics Engineers     

Titanium dioxide coated cementitious materials for air purifying purposes: Preparation,characterization and toluene removal potential

This work presents promising results for air purification by heterogeneous photocatalysis on new titanium dioxide loaded cementitious materials. A set of eight concretes and plasters is enriched with TiO₂ photocatalyst by dip-coating and/or sol–gel methods.     

Modeling of 1,3‐Butadiene Solution Polymerizations Catalyzed by Neodymium Versatate

The control of polymerization conditions and final properties of polybutadiene produced through solution polymerizations constitute an important industrial challenge, which can be tackled with help of mathematical models. For this reason, the present work focus on the development of a phenomenological mathematical model, and estimation of the respective model parameters, in order to describe the kinetics of 1,3‐butadiene solution polymerizations catalyzed by neodymium versatate. The proposed model can be used to predict some important final properties of polybutadiene resins, including the cis‐content and average molecular weights, and the evolution of operation conditions that are used at plant site to monitor the course of the reaction, including the reaction temperature and pressure. Given the low required computation times, the proposed model can be used for purposes of monitoring and control in actual industrial sites. POLYM. ENG. SCI., 59:2290–2300, 2019. © 2019 Society of Plastics Engineers     

Creating Directionality in Nanoporous Carbon Materials: Adjustable Combinations of Structural and Chemical Gradients

The properties of porous materials benefit from hierarchical porosity. A less noted element of hierarchy is the occurrence of directionality in functional gradient materials. A sharp boundary is replaced by a transition from one feature to the next. The number of cases known for porous materials with either structural or chemical gradients is small. A method capable of generating combinations of structural and chemical gradients in one material does not exist. Such a method is presented with a focus on silver and nitrogen containing carbon materials because of the potential of this system for electrocatalytic CO₂ reduction. A structural gradient results from controlled separation using ultracentrifugation of a binary mixture of template particles in a resorcinol–formaldehyde (RF) sol as carbon precursor. A new level of complexity can be reached, if the surfaces of the template particles are chemically modified. Although the template is removed during carbonization, the modification (Ag, N) becomes integrated into the material. Understanding how modified and unmodified large and small particles sediment in the RF sol enables almost infinite variability of combinations: chemically graded but structurally homogeneous materials and vice versa. Ultimately, a material containing one structural gradient and two chemical gradients with opposing directions is introduced.     

Method for quantitative evaluation of kinetic constants in olefin polymerizations. II. Kinetic study of a high‐activity Ziegler–Natta catalyst used for bulk propylene polymerizations

A method for quantitative evaluation of kinetic constants in Ziegler–Natta and metallocene olefin polymerizations presented previously (Matos, V.; Mattos Neto, A. G.; Pinto, J. C. J Appl Polym Sci 2001, 79, 2076) is adapted to allow the estimation of kinetic constants for bulk propylene polymerizations by using a conventional fourth‐generation high‐activity Ziegler–Natta catalyst (HAC). In this particular case, reaction rate profiles are not available, so that estimation of kinetic data must rely on average polymer yields. The method comprises some fundamental steps, including the initial design of a statistical experimental plan, the execution of the designed experiments, the development of simple mathematical models to describe the polymerization, and the estimation of kinetic parameters from available yields, gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) data. It is shown that the proposed method allows the successful interpretation of experimental olefin polymerization data and the quantitative evaluation of kinetic parameters, which can be inserted into a process simulator to provide an accurate picture of actual industrial plant behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3226–3245, 2002