Traveling dark-bright solitons in a reduced spin-orbit coupled system: application to Bose-Einstein condensates

In the present work, we explore the potential of spin-orbit (SO) coupled Bose-Einstein condensates to support multi-component solitonic states in the form of dark-bright (DB) solitons. In the case where Raman linear coupling between components is absent, we use a multiscale expansion method to reduce the model to the integrable Mel'nikov system. The soliton solutions of the latter allow us to reconstruct approximate traveling DB solitons for the reduced SO coupled system. For small values of the formal perturbation parameter, the resulting waveforms propagate undistorted, while for large values thereof, they shed some dispersive radiation, and subsequently distill into a robust propagating structure. After quantifying the relevant radiation effect, we also study the dynamics of DB solitons in a parabolic trap, exploring how their oscillation frequency varies as a function of the bright component mass and the Raman laser wavenumber

Minimum information about a protein affinity reagent (MIAPAR)

This is a proposal developed within the community as an important first step in formalizing standards in reporting the production and properties of protein binding reagents, such as antibodies, developed and sold for the identification and detection of specific proteins present in biological samples. It defines a checklist of required information, intended for use by producers of affinity reagents, qualitycontrol laboratories, users and databases. We envision that both commercial and freely available affinity reagents, as well as published studies using these reagents, could include a MIAPAR-compliant document describing the product’s properties with every available binding partner. This would enable the user or reader to make a fully informed evaluation of the validity of conclusions drawn using this reagent

Surface Properties of Antibodies and their Complexes with Antigens Studied by LLPC

The main objective of this thesis was to gain further insight into the relationship between the exposed surfaces and the functional properties of antibodies and their complexes with antigens in solution. To study this relationship, a new technique, liquid-liquid partition chromatography (LLPC) in aqueous two-phase systems, was developed further with respect to sensitivity, selectivity and reproducibility. The capacity of LLPC to compare the surface properties of antibodies in relation to their antigen specificity was explored. The usefulness of LLPC for examination of the events upon binding of antigen and for analysis of surface properties of antigen-antibody complexes in relation their structural/functional properties were studied. In this study, it was shown that LLPC in aqueous PEG-dextran two-phase systems offers the unique possibilities of comparing the overall surface properties of intact antibodies and antigen-antibody complexes in solution. A remarkable relationship between the surface of an antibody´s combining site and its chromatographic behaviour was found. LLPC provided the means to screen the antigen-binding sites of unliganded antibodies for differences/similarities in exposed surfaces even in those cases when the specificities of the antibodies were unknown. Our data suggest that antibodies may be regarded as being constructed of highly solvent-exposed, dominant CDRs of variable shape and size which, depending on the actual isotype, are grafted onto different scaffoldings of basically conserved structure. Moreover, different conformational (isomeric) forms of antibodies and enzymes could be detected and even separated using LLPC. Furthermore, the results demonstrated that LLPC could be used to examine the events upon binding of ligand by both antibodies and enzymes. The surface properties of antigen-antibody complexes were found to be dependent on the variable regions of the antibodies, the nature of the antigen, and/or possible conformational changes induced by ligand-binding

Novel type of protein chip for multiplex detection of autoantibodies.

Evaluation of: Akada J, Kamei S, Ito A et al. A new type of protein chip to detect hepatocellular carcinoma-related autoimmune antibodies in the sera of hepatitis C virus-positive patients. Proteome Sci. 11(1), 33 (2013). Unlocking the proteome and delivering biomarkers to the clinic will be critical for early and improved diagnosis and prognosis. Conventional protein microarrays have evolved as a promising proteomic technology with great potential for protein expression profiling in health and disease. In this study, Akada et al. explore a new type of protein chip, interfaced with a dual-color fluorescence-based read-out, for screening of autoantibodies in serum. Uniquely, the recombinant antigens were microarray adapted by molecular design to contain a five-cysteine tag for immobilization and green fluorescent protein for detection (color 1). The engineered antigens were immobilized on in-house-designed maleimide-incorporated diamond-like carbon substrates and subsequently heat treated in a solution of denaturing and reducing agents before any specifically bound serum autoantibodies were detected (color 2). The authors used a 4-plex array targeting hepatocellular carcinoma-related autoantibodies in the sera of hepatitis C virus-positive patients as model system to demonstrate proof-of-concept