Search

Abstract Background Intra-cellular and inter-cellular protein translocation can be observed by microscopic imaging of tissue sections prepared immunohistochemically. A manual densitometric analysis is time-consuming, subjective and error-prone. An automated quantification is faster, more reproducible, and should yield results comparable to manual evaluation. The automated method presented here was developed on rat liver tissue sections to study the translocation of bile salt transport proteins in hepatocytes. For validation, the cholestatic liver state was compared to the normal biological state. Results An automated quantification method was developed to analyze the translocation of membrane proteins and evaluated in comparison to an established manual method. Firstly, regions of interest (membrane fragments) are identified in confocal microscopy images. Further, densitometric intensity profiles are extracted orthogonally to membrane fragments, following the direction from the plasma membrane to cytoplasm. Finally, several different quantitative descriptors were derived from the densitometric profiles and were compared regarding their statistical significance with respect to the transport protein distribution. Stable performance, robustness and reproducibility were tested using several independent experimental datasets. A fully automated workflow for the information extraction and statistical evaluation has been developed and produces robust results. Conclusions New descriptors for the intensity distribution profiles were found to be more discriminative, i.e. more significant, than those used in previous research publications for the translocation quantification. The slow manual calculation can be substituted by the fast and unbiased automated method.

In this paper, a processing chain is proposed for enhancing larger-scale building structures in magnetometer data using the continuous wavelet transform for extracting the horizontal location, depth, and homogeneity (or shape) of subsurface objects. Even though the values estimated from our data do not clearly describe the archaeological site, they are used as a filter step for removing objects whose depth and homogeneity fall outside a predefined range. This yields a binary map, where valid points represent the horizontal source positions of magnetic anomalies. In a second step, curvilinear subsets of points are identified on a larger scale by the tensor voting framework indicating archaeological relevant structures, such as arcs and lines. Here, a point casts votes on neighbouring points and their values depend on the distance, and relative position of the points. All votes are summed up and the final value discriminates, whether a certain point (and therefore a magnetic source) is part of a salient curve (e.g. arc, line). Thresholding removes points with lower values while keeping those with larger values. Although the result shows many geometric features, it still needs to be combined with other data, e.g. from aerial photography or excavations. In combination, the extracted features continue those structures in the aerial photograph, thus expanding the knowledge about the archaeological site. [ABSTRACT FROM AUTHOR]

The idea of a “common artefact” is a useful metaphor for the design of CSCW systems. Our ACCT model of a common artefact describes structural elements that provide awareness about the work of others. The ACCT model identifies actors, contents, conversations, and tools as the central components of a common artefact, arranged on a shared background. The elements of a common artefact provide both a background visualization of the activity, but also permit dynamic notification of particular events. We explore this process of notification, which is composed of a selection and a presentation stage. We identify the critical factors of the process, in particular we highlight techniques related to temporal and spatial distortion. The framework helps to prepare design decisions of multi-user systems more consciously. [ABSTRACT FROM AUTHOR]

Reports on the use of both ultrasound images and three-dimensional animated heart models as common artifacts to support communication between medical professionals. Augmented-reality communication for diagnostic tasks in cardiology; Overview of the CardiAssist project; Use of an augmented reality scene as a common artefact to support communication between healthcare professionals.