It has been suggested that the maximum magnitude of colossal magnetoresistance occurs in mixed-valent manganites with a tolerance factor t = 0.96 ͓Zhou, Archibald, and Goodenough, Nature ͑London͒ 381, 770 ͑1996͔͒. However, at t Ϸ 0.96 most manganites have relatively low values of the metal-insulator transition temperature T MI ͑ϳ60-150 K͒. Here, we report that a 50 Å La 0.9 Sr 0.1 MnO 3 thin film with t = 0.96 grown on a ͑100͒ SrTiO 3 substrate has a metal-insulator transition above room temperature, which represents a doubling of T MI compared with its value in the bulk material. We show that this spectacular increase of T MI is a result of the epitaxially compressive strain-induced reduction of the Jahn-Teller distortion.

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Allergic diseases are major diseases involving approximately 22% of world population. In recent years, accumulated evidence suggests that apart from IgE, allergens may provoke immediate allergic reactions via other pathways such as IgG, toll like receptor (TLR) dependent ones. In addition, large numbers of low molecular weight molecules (LMWM) such as sphingosine-1-phosphate and iodinated contrast agents have been observed to cause allergy. Therefore, the current definition of allergy, a group of IgE mediated diseases appears difficult to cover all allergic reactions. Since even IgE dependent allergic reactions are carried out through activation of mast cells and basophils, and all allergens mentioned above can activate these cells, we hypothesize that allergic reactions are mast cell and basophil mediated inflammatory process as it is the activated mast cells and basophils that initiate the pathological process of the immediate allergic reactions, whereas IgE only serves as one of the activators of these cells.

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