HemoCue®, an Accurate Bedside Method of Hemoglobin Measurement?

Objective. Evaluate the accuracy of this bedside method to determinehemoglobin (Hb) concentration in general surgery over a wide range of Hbvalues and to determine potential sources of error. Methods. Accuracy of Hbmeasurement using HemoCue® (AB Leo Diagnostics, Helsinborg, Sweden) wasassessed in 140 surgical blood samples using 7 HemoCue® devices incomparison with a CO-Oximeter (IL 482, Instrumentation Laboratory,Lexington, MA). To analyze potential sources of error, packed red cells andfresh frozen plasma were reconstituted to randomized Hb levels of 2-18g/dL. Results. In the surgical blood samples, the Hb concentrationdetermined by the CO-Oximeter (HbCOOX) ranged from 5.1 to 16.7 g/dL and theHb concentration measured by HemoCue® (HbHC) from 4.7 to 16.0 g/dL. Bias(HbCOOX - HbHC) between HbCOOX and HbHC was 0.6 ± 0.6 g/dL(mean ± SD) or 5.4 ± 5.0% (p < 0.001). Also in thereconstituted blood, the bias between HbCOOX and HbHC was significant (0.2± 0.3 g/dL or 2.1 ± 3.2%; p < 0.001). Themicrocuvette explained 68% of the variability between HbCOOX andHbHC. HemoCue® thus underestimates the Hb concentration by2-5% and exhibits a 8-10 times higher variability withonly 86.4% of HbHC being within ± 10% of HbCOOX.Conclusion. Although the mean bias between HbCOOX and HbHC was relativelylow, Hb measurement by HemoCue® exhibited a significant variability.Loading multiple microcuvettes and averaging the results may increase theaccuracy of Hb measurement by HemoCue

Protein pocket and ligand shape comparison and its application in virtual screening

Understanding molecular recognition is one major requirement for drug discovery and design. Physicochemical and shape complementarity between two binding partners is the driving force during complex formation. In this study, the impact of shape within this process is analyzed. Protein binding pockets and co-crystallized ligands are represented by normalized principal moments of inertia ratios (NPRs). The corresponding descriptor space is triangular, with its corners occupied by spherical, discoid, and elongated shapes. An analysis of a selected set of sc-PDB complexes suggests that pockets and bound ligands avoid spherical shapes, which are, however, prevalent in small unoccupied pockets. Furthermore, a direct shape comparison confirms previous studies that on average only one third of a pocket is filled by its bound ligand, supplemented by a 50 % subpocket coverage. In this study, we found that shape complementary is expressed by low pairwise shape distances in NPR space, short distances between the centers-of-mass, and small deviations in the angle between the first principal ellipsoid axes. Furthermore, it is assessed how different binding pocket parameters are related to bioactivity and binding efficiency of the co-crystallized ligand. In addition, the performance of different shape and size parameters of pockets and ligands is evaluated in a virtual screening scenario performed on four representative target

The 1356 Basel earthquake: an interdisciplinary revision

Within historical times one of the most damaging events in intra-plate Europe was the 1356 Basel earthquake. Given its significance for assessing regional seismic hazard in central Europe, an interdisciplinary project was launched in 2005 to re-explore this event. Our effort aimed to incorporate techniques from history, seismology, archaeology, paleoseismology and engineering. New and reinterpreted historical data from Basel and its surroundings plus archaeological findings on buildings that survived the event and still exist enabled this macroseismic assessment. Palaeoseismological studies combined with historical evidence provided additional data. For the surrounding areas, archaeology offers sparse information on some castles and churches, sometimes supported by historical records. A contemporary source allows some reconstruction of the stronger fore- and aftershocks. This expanded information base improves our sense of the event's damage and consequences. For the city of Basel, the relatively abundant archaeological data allowed us to assess statistically the macroseismic intensity at IX, although the pattern of damage was scattered. Data points for the expected area of damage around Basel are not distributed regularly. The absence of historical and archaeological findings for southern Germany might be due to archival problems; future investigation may improve this situation. Our results confirm that the Basel earthquake was the most destructive known for central Europe. Intensities up to VIII are found within a radius of about 30 km. Analysing the macroseismic field confirms our former assessment of the event and shows an epicenter located about 10 km south of Basel. The most probable range for the moment magnitude Mw is between 6.7 and 7.

Design agency:prototyping multi-agent systems in architecture

This paper presents research on the prototyping of multi-agent systems for architectural design. It proposes a design exploration methodology at the intersection of architecture, engineering, and computer science. The motivation of the work includes exploring bottom up generative methods coupled with optimizing performance criteria including for geometric complexity and objective functions for environmental, structural and fabrication parameters. The paper presents the development of a research framework and initial experiments to provide design solutions, which simultaneously satisfy complexly coupled and often contradicting objectives. The prototypical experiments and initial algorithms are described through a set of different design cases and agents within this framework; for the generation of façade panels for light control; for emergent design of shell structures; for actual construction of reciprocal frames; and for robotic fabrication. Initial results include multi-agent derived efficiencies for environmental and fabrication criteria and discussion of future steps for inclusion of human and structural factors