Measuring through the microscope: Development and evolution of stereological methods

Obtaining, by means of microscopy, meaningful measurements pertaining to spatial structures requires methods which allow three-dimensional quantitative information to be derived from the reduced information available on the two-dimensional flat sections of the structure. The most powerful methods to that effect are those of stereology which are based on mathematical principles. This paper reviews the early invention of these methods, which sought to solve practical problems, and their further evolution as more rigorous mathematical foundations were developed. It is demonstrated that stereological methods are essentially sampling methods and that newer trends provide new and sound solutions to old and elusive problems, such as anisotropy or particle number and size.     

The intoxicated witness: Effects of alcohol on identification accuracy from showups.

The effect of alcohol on identification accuracy is potentially an important topic. This study examined the effects of alcohol consumption on identification accuracy from showups, the identification procedure most likely to be used by police with intoxicated witnesses. The blood alcohol level of people exposed to a target was measured. In the target-present showup condition, blood alcohol level was not significantly related to correct identification rate. In the target-absent showup condition, the higher the blood alcohol level, the more people were likely to make a false identification. Implications for law enforcement and future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of processing parameters on quality factors of one-shot hybrid structures made by RTM

This paper is dealing with the influence of processing parameters for manufacturing of steel–carbon-fiber-reinforced-plastic (CFRP) hybrid plates by using the one-shot-hybrid resin-transfer-moulding (OSH-RTM) process. A design of experiments study was carried out. The quality of the manufactured parts was quantified by the bending modulus, the apparent interlaminar shear strength (ILSS), the maximum deflection and the density of the CFRP. The following changeable processing parameters were chosen: mould temperature, resin temperature, change in mass flow and maximum injection pressure. It is shown that the mould temperature and the change in mass flow show significant impact on the flexural modulus, density and maximum deflection of the plate while there is no significant impact on the apparent ILSS. Furthermore, the interaction between the mould temperature and resin temperature is having an influence on the flexural modulus and density.     

Influence of textile parameters on the in‐plane permeability characteristics of non‐crimped fabric preforms

Material parameters such as the permeability of dry reinforcing textiles are key variables for modern composite production using liquid composite molding (LCM) technique. Nowadays numerical filling simulations are required for predicting the mold filling behavior. Inaccurate predictions can lead to a high risk of air inclusion and corresponding need for cost‐intense revision of the mold design. Permeability values of the textiles used in the process are basic requirements for a numerical filling simulation, since the permeability is directly linked to the filling behavior. Nevertheless, the permeability values of non‐crimped fabrics (NCF) which are used for aerospace and automotive structures are rare. In this study the influence of textile parameters of NCF on the in‐plane permeability has been investigated using a capacitive in‐plane permeability measurement technology. The results show the influence of the roving filament number as well as the used stitch length on the in‐plane permeability. It is confirmed that the textile grammage is not affecting the in‐plane permeability of NCF reinforcements. The results of this study are valuable for textile selection with specific permeability data as well as for numerical filling simulations. POLYM. COMPOS., 37:1854–1863, 2016. © 2015 Society of Plastics Engineers     

Virological treatment failure of protease inhibitor therapy in an unselected cohort of HIV-infected patients

OBJECTIVE: To determine the rate of virological treatment failure with protease inhibitor therapy in unselected patients and to assess underlying risk factors. DESIGN AND SETTING: Retrospective study in two German tertiary care treatment centres. PATIENTS: A total of 198 HIV-infected patients treated with protease inhibitors in 1996. MAIN OUTCOME MEASURES: Levels of HIV RNA 1-6 months after start of treatment; definition of treatment failure of < 1 log10 reduction in plasma HIV RNA within 6 months after starting protease inhibitor therapy; multivariate analysis of risk factors for treatment failures. RESULTS: A total of 226 treatment episodes with protease inhibitors were evaluable (saquinavir, 83; ritonavir, 47; indinavir, 96). The rate of virological treatment failure was 44% (saquinavir, 64%; ritonavir, 38%; indinavir, 30%). In a multivariate analysis, the following independent risk factors for virological failure were found: CD4 cell count, pretreatment with antiretroviral drugs (number), and protease inhibitor (compound). The relative risk reduction for each CD4 cell count increase was 0.997 (P = 0.012), 2.64 for pretreatment with one or two drugs versus no drug (P = 0.05), 2.97 for pretreatment with more than two drugs versus no drug (P = 0.05), and 4.62 for treatment with saquinavir versus indinavir (P = 0.001). CONCLUSION: An unexpectedly high rate of virological treatment failure of protease inhibitor therapy was found in an unselected cohort of HIV-infected patients. Response to antiretroviral combination therapy in normal clinical practice may considerably differ from results of randomized clinical trials. Further studies are warranted to find optimal treatment strategies for both initial and salvage therapy.     

Negative Priming Effects in Children Engaged in Nonspatial Tasks: Evidence for Early Development of an Intact Inhibitory Mechanism.

Three experiments are reported that examined conceptual negative priming effects in children 5 to 12 years of age. Experiment 1 used a negative priming variant of a flanker task requiring the naming of a central color blob flanked by irrelevant distractors. Experiment 2 used a negative priming variant of the Stroop color-word task. Experiment 3 used a same-different matching task with novel 3-D shapes. Results revealed significant and equivalent magnitudes of negative priming across the tested age groups for all 3 tasks. It is concluded that the inhibitory mechanism underlying conceptual (i.e., identity or semantic) negative priming in visual selective attention tasks is intact in young children. Because the findings and conclusions diverge from the developmental literature on negative priming, the authors attempt to reconcile the contradictions by pinning down the reasons for the discrepancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Surface condition monitoring of unalloyed steel sheet by measuring ferromagnetic properties and using multi-parameter data analysis

Initial investigations into coated steel sheets were conductted to verify whether sample- and batch-independent classification of surface condition can be achieved with multi-inductive data acquisition and multivariate data analysis without using a priori information. Using an ‘integrated sensor’ - a multi-inductive sensor - it is possible to obtain parameters of eddy currents, hysteresis and noise voltage with PC control. These parameters are the input values of multivariate data analysis.     

Performance of construction materials in multiphase liquid/solid flows

The transport of corrosive liquids containing solids, in conventional energy and process technology as, for example, in oil and gas production, places high demands on the selection of materials for plant construction. A discussion on the chemo-mechanical load demonstrates the significance of hydrodynamics in selecting the test method. Choosing a pipe with an abrupt expansion of cross-section as a flow model yields a new method of simulating operation conditions. By subjecting ferrous materials used for hydraulic machinery to representative media from three important industries, a broad spectrum of results can be obtained. Classification of the results leads to four basic types of mass loss behaviour in materials as functions of flow rate. These findings yield guidelines for the selection of materials and the dimensioning of flow equipment.