Flow behavior and dynamic transformation of titanium alloy Ti62A during deformation at different temperatures and strain rates

The effect of deformation temperature and strain rate on the hot deformation behavior and dual-phase microstructure evolution of the titanium alloy Ti62A was examined using electron backscatter diffraction. In general, the activation energy of Ti62A during steady-state deformation in the ( α + β ) phase is 295 kJ mol ^−1 . The primary recovery mechanisms of the β phase during hot deformation are dynamic recovery and dynamic recrystallization (DRX). Moreover, discontinuous DRX occurs at low temperatures and high strain rates, whereas continuous DRX occurs at high temperatures and low strain rates. Furthermore, high strain rates in the ( α + β ) phase and high deformation temperatures are advantageous to dynamic phase changes during dynamic transformation (DT). The β phase penetrates the lamellar α _s phase, causing fragmentation and spheroidization of the α _s phase. Finally, DT begins more easily in the fine α _s phase than in the coarse α _p phase

Immunologic mapping of glycomes: implications for cancer diagnosis and therapy

Cancer associated glycoconjugates are important biomarkers, as exemplified by globo-H, CA125, CA15.3 and CA27.29. However, the exact chemical structures of many such biomarkers remain unknown because of technological limitations. In this article, we propose the “immunologic mapping” of cancer glycomes based on specific immune recognition of glycan structures, which can be hypothesized theoretically, produced chemically, and examined biologically by immuno-assays. Immunologic mapping of glycans not only provides a unique perspective on cancer glycomes, but also may lead to the invention of powerful reagents for diagnosis and therapy

Immunologic glycosphingolipidomics and NKT cell development in mouse thymus

Invariant NKT cells are a hybrid cell type of Natural Killer cells and T cells, whose development is dependent on thymic positive selection mediated by double positive thymocytes through their recognition of natural ligands presented by CD1d, a non-polymorphic, non-MHC, MHC-like antigen presenting molecule. Genetic evidence suggested that β-glucosylceramide derived glycosphingolipids (GSLs) are natural ligands for NKT cells. N-butyldeoxygalactonojirimycin (NB-DGJ), a drug that specifically inhibits the glucosylceramide synthase, inhibits the endogenous ligands for NKT cells. Furthermore, we and others have found a β-linked glycosphingolipid, isoglobotriaosylceramide (iGb3), is a stimulatory NKT ligand. The iGb3 synthase knockout mice have a normal NKT development and function, indicating that other ligands exist and remain to be identified. In this study, we have performed a glycosphingolipidomics study of mouse thymus, and studied mice mutants which are deficient in β-hexosaminidase b or α-galactosidase A, two glycosidases that are up- and down-stream agents of iGb3 turnover, respectively. Our mass spectrometry methods generated a first database for glycosphingolipids expressed by mouse thymus, which are specifically regulated by rate-limiting glycosidases. Among the identified thymic glycosphingolipids, only iGb3 is a stimulatory ligand for NKT cells, suggesting that large scale fractionation, enrichment and characterization of minor species of glycosphingolipids, be necessary for identifying additional ligands for NKT cells. Our results also provide early insights into cellular lipidomics studies, with a specific focus on the important immunological functions of glycosphingolipids