A model for rod-coil block copolymers

A coarse-grained model for studying the phase behavior of rod-coil block copolymer systems on mesoscopic length scales is proposed. The polymers are represented on a particle level (monomers, rods) whereas the interactions between the system’s constituents are formulated in terms of local densities. This conversion to density fields allows an efficient Monte Carlo sampling of the phase space. We demonstrate the applicability of the model and of the simulation approach by illustrating the formation of typical micro-phase separated configurations for exemplary model parameters.     

Relative validation of a food frequency questionnaire for national health and nutrition monitoring

Background  

Validation of a food frequency questionnaire (FFQ) is important as incorrect information may lead to biased associations. Therefore the relative validity of an FFQ developed for use in the German Health Examination Survey for Adults 2008-2011 (DEGS) was examined.     

Multiple systems for cognitive control: Evidence from a hybrid prime-Simon task.

Cognitive control resolves conflicts between appropriate and inappropriate response tendencies. Is this achieved by a unitary all-purpose conflict control system, or do independent subsystems deal with different aspects of conflicting information? In a fully factorial hybrid prime-Simon task, participants responded to the identity of targets displayed at different nominally irrelevant screen locations, preceded by nominally irrelevant, consciously or nonconsciously perceived primes. The response required by the target's identity could match or mismatch (a) the target's location, and (b) the prime's identity, resulting in potential conflict (a) across and (b) within stimulus domains. Conflict effects were investigated within and across trials. Results suggest that (i) nonconsciously perceived information elicits within-trial control, but—unlike consciously perceived information—no across-trial behavioral modulation; (ii) separate subsystems deal with conflicts arising from different stimulus domains; and (iii) occasional apparent interactions between domains reflect a particular difficulty in reactivating a just-discarded response (reactivation aversion effect, RAE). (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A COMPUTER MODEL OF MYOCARDIAL SQUEEZING AND INTRAMYOCARDIAL FLOW DURING GRADED CORONARY ARTERY STENOSIS IN THE PRESENCE OF CORONARY SINUS INTERVENTIONS

A mathematical model of the left coronary circulation is used to calculate phasic arterial and intramyocardial flows under normal conditions, gradual stenosis, and full occlusion of the left anterior descending coronary artery. Experimental data reported in literature are compiled to derive a mathematical formula for the physiologic link between two model parameters: the resistance across the stenosis and the extravasal squeezing pressure within the LAD-dependent region of the myocardium. Matching pairs of resistance and decrease in squeezing form “infarction traces.” Model simulations yield the changes in coronary and intramyocardial flows along these infarction traces. The model was applied to alternating brief coronary sinus occlusions and coronary sinus release. The retrograde blood flow from the coronary veins to the capillaries during coronary sinus occlusion was estimated to range between 47% and 88% of the forward blood flow under patent coronary sinus conditions.     

Blue-green architecture: A case study analysis considering the synergetic effects of water and vegetation

Blue–green infrastructure is a network of natural and near-natural areas that has a positive effect on the quality of urban environment. This multifunctional planning approach addresses different issues and objectives depending on whether the focus is on the blue (water) or the green (vegetation) elements. Green-motivated projects aim to densify urban vegetation and include the growing sector of building greening. A good climatic effect of vegetation can be achieved by sufficient irrigation. In many cases, this approach results in additional water requirements. Blue-motivated projects consider water accumulation in cities (e.g., by heavy rainfall) as a waste product and look for solutions for local drainage and evaporation. These planning approaches offer only one-sided solutions and create no sufficient interfaces between water availability and water demand. Based on four case studies, this work examines the extent to which blue–green projects take advantage of the possibilities for the synergetic use of resources. The projects are analyzed graphically by applying the daily tools of architects as a scientific method. A graphic presentation of the blue and green components makes existing solutions and missing links visible. Analytical results show that buildings can be considered to be an interface for blue–green systems. Moreover, the possible synergies are often overlooked during the planning process. This fact highlights the need for a new planning approach that interlinks blue and green aspects that are already in the early planning stages.     

Characterization of catalysts in their active state by adsorption microcalorimetry: Experimental design and application to sulfated zirconia

A method to characterize the surface sites of catalysts in their active state by adsorption microcalorimetry was developed. A calorimeter cell was used as a flow-type reactor, and the skeletal isomerization of n-butane (1 kPa) at 378 K and atmospheric pressure proceeded at comparable rates and with the same states of induction period, maximum and deactivation phase as in a tubular reactor. The reaction was run for selected times on stream and after the removal of weakly adsorbed species, n-butane or isobutane were adsorbed at 313 K. The surface of activated sulfated zirconia was characterized by at least two different sites for n-butane adsorption, a small group of sites (about 20 μmol g^?1) that yielded heats of 50–60 kJ mol^?1 and sites that were populated at higher pressures (above about 5 hPa n-butane) and yielded heats of about 40 kJ mol^?1. The strongly interacting sites disappear during the induction period and are proposed to be the sites where the isomerization reaction is initiated.     

Überwachung der Plasmahomogenität

Monitoring plasma homogeneity A new imaging system has been built up for the fast qualitative monitoring of plasma processes. It is designed to analyze the spatial distribution of the plasma’s emission intensity at different wavelengths. The system consists of a liquid crystal tunable filter for wavelength selection and a CCD‐camera. Its applicability is presented for non‐polymerizing argon plasmas and polymerizing acetylene plasmas. Our investigations were carried out with focus on the effect of the process pressure on the homogeneity of the plasma emission and the resulting layer deposition. Both the emission’s uniformity as well as the homogeneity of the deposition are affected by the process pressure. Low process pressures are favorable for both of the named parameters.     

Überwachung von Niederdruck‐Plasmaanlagen

Monitoring of low pressure plasma systems The optical emission spectroscopy (OES) is a very flexible and easy to use method to monitor industrial plasma processes. By directly monitoring the plasma itself many additional factors influencing low pressure plasma processes can be observed. First of all factors that can not be controlled directly play an important role in this context. Examples are contaminations and leaks in the plasma system. These can negatively influence the reproducibility of production processes. In this paper the effect of a leak on the coating and the plasma process is being shown. Additionally the detection of contaminations and sealing problems in a microwave plasma source is being demonstrated. By using the correlations being presented the OES can be used to continually monitor low pressure plasma systems and thus enhance reproducibility of industrial low pressure plasma processes.