Efficient, Near Complete and Often Sound Hybrid Dynamic Data Race Prediction (extended version)

Dynamic data race prediction aims to identify races based on a single program run represented by a trace. The challenge is to remain efficient while being as sound and as complete as possible. Efficient means a linear run-time as otherwise the method unlikely scales for real-world programs. We introduce an efficient, near complete and often sound dynamic data race prediction method that combines the lockset method with several improvements made in the area of happens-before methods. By near complete we mean that the method is complete in theory but for efficiency reasons the implementation applies some optimizations that may result in incompleteness. The method can be shown to be sound for two threads but is unsound in general. We provide extensive experimental data that shows that our method works well in practice.Comment: typos, appendi

Adaptation of the AAPOR Final Disposition Codes for the German Survey Context (Version 1.0)

Detailed and precise documentation is the key to scientific research and of particular importance for high-quality data collection. An important parameter for each survey is the response rate. It reflects how many persons initially invited to participate finally took part in a survey interview. In any case, every survey based on a probability sample should report its response rate, since it provides first and easily assessable information about the data collection process. The American Association for Public Opinion Research (AAPOR) has proposed Standard Definitions that include final disposition codes as guidelines for reporting of response rates. These definitions take various modes of data collection into account. However, the final disposition codes proposed by AAPOR are based on sampling and data collection practices in the context of the United States. To date, there is no clear guidance on how to adapt these definitions in a comparable manner for the German context. This survey guideline aims to close this information gap and offers operational definitions for the AAPOR final disposition codes that are applicable in the German context

Phage capsid nanoparticles with defined ligand arrangement block influenza virus entry

Multivalent interactions at biological interfaces occur frequently in nature and mediate recognition and interactions in essential physiological processes such as cell-to-cell adhesion. Multivalency is also a key principle that allows tight binding between pathogens and host cells during the initial stages of infection. One promising approach to prevent infection is the design of synthetic or semisynthetic multivalent binders that interfere with pathogen adhesion1,2,3,4. Here, we present a multivalent binder that is based on a spatially defined arrangement of ligands for the viral spike protein haemagglutinin of the influenza A virus. Complementary experimental and theoretical approaches demonstrate that bacteriophage capsids, which carry host cell haemagglutinin ligands in an arrangement matching the geometry of binding sites of the spike protein, can bind to viruses in a defined multivalent mode. These capsids cover the entire virus envelope, thus preventing its binding to the host cell as visualized by cryo-electron tomography. As a consequence, virus infection can be inhibited in vitro, ex vivo and in vivo. Such highly functionalized capsids present an alternative to strategies that target virus entry by spike-inhibiting antibodies5 and peptides6 or that address late steps of the viral replication cycle

Cationic Dye for the Specific Determination of Sulfated Polysaccharides

A new, highly specific toluidine blue assay for the determination of sulfated polysaccharides is reported. Sulfated polysaccharides may be specifically determined at pH 1 in the presence of carboxylated polysaccharides and phosphorylated molecules such as nucleic acids. In addition, performing the assay at pH 1 extended the linear dynamic range for fucoidan up to 3 g/L but lowered the sensitivity in comparison with pH 7. For a color change at neutral pH, at least a sulfated disaccharide is required, whereas at pH 1, the detection was negative even for a sulfated maltose. A comparison of the fucoidan concentration in crude algae determined by the toluidine blue assay at pH 1 and gel permeation chromatography confirmed the accuracy and specificity of the colorimetric method. The limit of quantitation for the toluidine blue assay at pH 1 was 0.62 g/L for fucoidan. For a deeper understanding of the interaction between the sulfated polysaccharides and the toluidine blue, spectroscopic constants were evaluated by Ketelaar plots for sulfate esters. The maximum value for the molar absorptivity was 4.07 × 104 L/(mol cm), indicating strong affinity. Similar behavior was obtained for fucoidan at pH 7 with a value of 4.46 × 103 L/mol