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Hui Yin

Publications and source records attributed to Hui Yin.

4 recordsLinked to original sources
PubMed2002

Slow dynamics and aging in a nonrandomly frustrated spin system.

A simple, non-disordered spin model has been studied in an effort to understand the origin of the precipitous slowing down of dynamics observed in supercooled liquids approaching the glass transition. A combination of Monte Carlo simulations and exact calculations indicates that this model exhibits an entropy-vanishing transition accompanied by a rapid divergence of time scales. Measurements of various correlation functions show that the system displays a hierarchy of time scales associated with different degrees of freedom. Extended structures, arising from the frustration in the system, are identified as the source of the slow dynamics. In the simulations, the system falls out of equilibrium at a temperature T(g) higher than the entropy-vanishing transition temperature and the dynamics below T(g) exhibits aging as distinct from coarsening. The cooling rate dependence of the energy is also consistent with the usual glass formation scenario.

Journal Article↗
PubMed2002

Patterns of immunoglobulin staining in paraffin-embedded malignant lymphomas.

The demonstration of immunoglobulin light chain restriction in paraffin-embedded B cell lymphomas is a capricious and difficult procedure that has been abandoned by many diagnostic laboratories. Using a combination of microwave antigen retrieval performed in a pressure cooker and proteolytic digestion with trypsin, we were able to demonstrate immunoglobulin light chain restriction in 66 B cell lymphomas comprising 25 follicular lymphomas, 29 diffuse large cell lymphomas, 6 small lymphocytic lymphomas, 2 mantle cell lymphomas, 1 nodal marginal zone lymphoma, 1 Burkitt lymphoma, 1 hairy cell leukemia, and 1 plasmacytoma. There was concordance of results in 13 cases in which flow cytometry immunoglobulin analyzes were performed. Perinuclear staining was demonstrated in all cases with dot-like staining of the Golgi present in 23 cases. Perinuclear staining occurred in combination with cytoplasmic staining in 12 cases and membrane staining in 8 cases with 12 lymphomas showing more than two patterns of staining.

Flow Cytometry↗
PubMed2002

Superheating antigen retrieval.

Heat-induced antigen retrieval in a variety of solutions has been shown to enhance the immunoreactivity of a wide range of antigens in routine formalin-fixed, paraffin-embedded tissues. Accurate time and temperature control is important for standardization and optimization of the procedure but is difficult to achieve. This study used a device to attain precise time and temperature control for antigen retrieval at 120 degrees C under 1.9 bar pressure. It compares the efficacy of this method with antigen retrieval in a conventional pressure cooker, by microwave heating at 98 degrees C, and ultrasound retrieval at 40 and 70 W for 40 and 100 seconds. Multitissue and multitumor blocks containing a spectrum of normal tissues and a variety of tumors, respectively, were used, and 42 routine diagnostic antibodies were applied with a standard peroxidase conjugated streptavidin technique. Sections in which antigen retrieval was not performed served as controls. The three heat-induced methods showed distinctly better immunostaining for all antigens compared with those obtained with ultrasound retrieval. The latter method did not produce consistent staining and intensity, and the extent of staining was only marginally better than sections not subjected to antigen retrieval. Superheating at 120 degrees C produced the best overall results with the exception of antibodies to cytokeratin clones Cam 5.2, AE1/3, and 34BE12 in which superheating resulted in slightly inferior immunostaining compared with heating in a pressure cooker and at 98 degrees C.

Antigens↗