Strength, Elastic Properties and Fiber-Matrix Interaction Mechanism in Geopolymer Composites.

The current geopolymers have limited mechanical strength against the effect of tension, which makes them susceptible to brittle failure. However, owing to their potential as a sustainable construction material, there is growing interest in improving the poor mechanical properties of geopolymers. This study experimentally investigated crucial properties of polypropylene-fiber-reinforced fly ash-based geopolymer composites.

First report of a KELnull phenotype in Peru and a lesson of invisible genetic disparity.

Blood banks in developing countries have limited capability to typify common blood groups creating disparities in the access to blood units for patients with rare blood genotypes. We report the case of a Peruvian woman with metastatic breast cancer with KELnull phenotype (K), a rare blood group characterized by the lack of expression of all Kell antigens on the red blood cells (RBCs). The molecular studies identified that the patient's RBCs were homozygous for the nonsense c.

Cutting edge: IL-21 derived from human follicular helper T cells acts as a survival factor for secondary lymphoid organ, but not for bone marrow, plasma cells.

IL-21 induces the differentiation of activated B lymphocytes into plasma cells (PC), but its direct effect on PC remains uncertain. This study analyzes the role of IL-21 on human in vivo-generated PC. IL-21R was clearly expressed on PC from the human tonsil, the lymph node, and the spleen (secondary lymphoid organs [SLO]) but barely on terminally mature bone marrow PC.

[Induction of protective antiamebic immunity in hamsters with heterologous antigens].

Two hundred and twenty-five Syrian golden hamsters were used. Twenty five of them served as the control group. All other hamsters were intradermal immunized, once a week for four weeks, with a mixture of amebic proteins, mixed with complete Freund adjuvant, obtained from 5 x 10(5) homogenized dead amebic trophozoites from five different strains.