Formulation effects on the distribution of pigment particles in paints

Modern water-borne paints are widely used in different areas of applications ranging from high-gloss lacquers to flat, scrub-resistant interior paints. From this point of view, the pigment volume concentration (PVC) is one key-parameter adjusting the desired application properties. In high-gloss paints, for example, a low PVC is required to accommodate the proper surface roughness to achieve a high gloss. Consequently, a high concentration of TiO₂ is needed to obtain a good hiding power at the same time. Flat paints nonetheless are highly filled due to cost reasons preferentially by CaCO₃ and the pigment binding capacity of the binder is crucial. In this work, paint formulations differing in PVC, and the type of binder or dispersing agent were investigated by various techniques concerning the distribution and aggregation of pigment particles, e.g. TiO₂. To get a detailed insight into the structure of the liquid paints and the corresponding dried paint films, suitable analytical tools were applied for characterization. The structure of the liquid paints was analyzed by remission light spectroscopy (RLS), disc centrifugation, cryogenic-replication transmission electron microscopy (Cryo-replica TEM) and cryogenic-scanning electron microscopy (Cryo-SEM). The pigment distribution in the corresponding dried paint films was examined by means of atomic force microscopy (AFM), TEM and RLS. The tendency of the TiO₂-pigments to form aggregates was found to depend on both: first on the type of binder used in the formulation and second on the employed dispersing agent. It is shown that only by adjusting the properties of the binder in combination with common dispersants, it is possible to get well-distributed TiO₂ particles within the paint. Correlation of application properties, e.g. gloss and blocking to the microscopic structure is presented.     

Detangler: Visual Analytics for Multiplex Networks

A multiplex network has links of different types, allowing it to express many overlapping types of relationships. A core task in network analysis is to evaluate and understand group cohesion; that is, to explain why groups of elements belong together based on the underlying structure of the network. We present Detangler, a system that supports visual analysis of group cohesion in multiplex networks through dual linked views. These views feature new data abstractions derived from the original multiplex network: the substrate network and the catalyst network. We contribute two novel techniques that allow the user to analyze the complex structure of the multiplex network without the extreme visual clutter that would result from simply showing it directly. The harmonized layout visual encoding technique provides spatial stability between the substrate and catalyst views. The pivot brushing interaction technique supports linked highlighting between the views based on computations in the underlying multiplex network to leapfrog between subsets of catalysts and substrates. We present results from the motivating application domain of annotated news documents with a usage scenario and preliminary expert feedback. A second usage scenario presents group cohesion analysis of the social network of the early American independence movement.     

The utility of the reasonable woman legal standard in hostile environment sexual harassment cases: A multimethod, multistudy examination.

The case of Ellison v. Brady (1991) was a landmark decision in establishing a new legal standard-the reasonable woman standard-for evaluating hostile environment allegations of sexual harassment and in relying, albeit indirectly, on social science evidence to support its decision. The authors review the legal standard in sexual harassment law, and the legal arguments and social science evidence underlying Ellison. The new standard could affect judgments broadly by sensitizing jurors to the situation of a female plaintiff, or it could affect judgments selectively by sensitizing only those people who might otherwise be especially insensitive to her situation. Five studies that focus on the effect of the reasonable woman standard on people's assessments of hostile environment sexual harassment indicate that the reasonable woman standard has modest, if any, effects on the judgments studied. Implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of separate slow and fast muscle precursor cells in vivo, prior to somite formation

We have examined the development of specific muscle fiber types in zebrafish axial muscle by labeling myogenic precursor cells with vital fluorescent dyes and following their subsequent differentiation and fate. Two populations of muscle precursors, medial and lateral, can be distinguished in the segmental plate by position, morphology and gene expression. The medial cells, known as adaxial cells, are large, cuboidal cells adjacent to the notochord that express myoD. Surprisingly, after somite formation, they migrate radially away from the notochord, becoming a superficial layer of muscle cells. A subset of adaxial cells develop into engrailed-expressing muscle pioneers. Adaxial cells differentiate into slow muscle fibers of the adult fish. We have named the lateral population of cells in the segmental plate, lateral presomitic cells. They are smaller, more irregularly shaped and separated from the notochord by adaxial cells; they do not express myoD until after somite formation. Lateral presomitic cells remain deep in the myotome and they differentiate into fast muscle fibers. Thus, slow and fast muscle fiber types in zebrafish axial muscle arise from distinct populations of cells in the segmental plate that develop in different cellular environments and display distinct behaviors.     

Gliomatosis cerebri

PURPOSE: To characterize gliomatosis cerebri on computed tomographic (CT) and magnetic resonance (MR) images. MATERIALS AND METHODS: MR and CT studies of 22 patients with cerebral gliomatosis were reviewed retrospectively. Tumor was confirmed with autopsy (n=5) or biopsy. Distribution and extent of disease were assessed, and disease progression was followed. RESULTS: Tumor involved at least two lobes of the brain in all patients, with extension to the corpus callosum in 12, basal ganglia and thalamus in 17, brain stem in three, and cerebellum in two patients. Widespread invasion with hyperintensity was noted on proton-density- and T2-weighted MR images. At CT, areas of hypo- or isoattenuation were noted, and no contrast enhancement occurred. Extent of tumor was greater on MR images than on concurrent CT scans in all patients. The MR findings closely correlated with the autopsy findings. CONCLUSION: Gliomatosis cerebri is best detected with MR imaging. The pattern is infiltrative with enlargement of cerebral structures.     

Heterogeneity of cognitive profiles in dementias of the Alzheimer type: theoretical aspects and clinical consequences

Presently, Alzheimer's disease can only be diagnosed with the coexistence of clinical symptoms and the presence of neuropathological alterations. Thus, in the absence of pre mortem biological markers, cognitive deficits form the starting point and the basis of inclusion criteria on which the clinician relies in order to make a putative diagnose of dementia of the Alzheimer type (DTA). Cognitive deficits should thus be accurately described through neuropsychological testing since it is essential to identify the cognitive deterioration patterns of the patients--in terms of selective impairment of cognitive functions--as well as the evolution of these patterns. Regarding this issue, the classical teaching of the Geneva school has proposed a homogeneous deterioration of the aphasic-apraxicagnosic syndrome into four stages. However, recent work does not support this hypothesis. On the contrary, these studies tend to show the presence of heterogeneity in neuropsychological manifestations of the disease. The aim of the present paper is to provide a critical review of this topic through a brief survey of the classical work and research that have recently been conducted. An analysis of the possible candidates responsible for the existence of this heterogeneity of cognitive profiles is presented. Finally, theoretical implications and clinical repercussions are discussed.     

Gaseous equilibria in the C-H-O ternary system at 500–2000 K, 0.1–10 atm

The complex gaseous equilibria of approximately 10,000 different compositions in the C-H-O ternary system containing up to 40 gaseous species have been calculated at temperatures of 500, 1000, 1500, and 2000 K for total pressures of 0.1, 1.0, and 10.0 atm. The results are represented by selected isoactivity curves of carbon and isobars of hydrogen and oxygen plotted on C-H-O Gibbs composition triangles. The effects of changing composition, temperature, and pressure upon the chemical equilibria in this system are analyzed. In addition, the role of the C-H-O system in selected industrial applications is briefly discussed, including the choice of gas mixtures for the carburization of metals; the extent of carbon deposition at various temperatures, pressures, and compositions in reforming and gasification processes; the free hydrogen partial pressure in the anode compartment of fuel cells and influence of water addition; the oxygen potential in the products of combustion engines; and chemically buffered gas mixtures in controlled atmospheres.     

Managing Change from the Top: Using Fact-Based Enforcement to Support Change Management Policies

No doubt about it, change is an ever-present fact of life in the dynamic environment of an IT data center. But how change is managed, and how change management is enforced, can make the difference between how efficiently an IT organization handles security, system availability, costs, and efficiency—or, how it does not. Unfortunately, change can be an organization's worst enemy if not controlled. Unauthorized and undocumented change results in serious threats to operational stability, security, and compliance posture. But change, when managed clearly and consistently, can also accelerate an organization's performance—that is, if strong change management processes and policies are enforced.