Ageing of polysulfone membranes in contact with bleach solution: Role of radical oxidation and of some dissolved metal ions

In water production plants using membrane processes, contact with chemicals such as chlorine plays an important role in membrane ageing. This experimental study was aimed at gaining a better understanding of the effect of hypochlorite cleaning solutions on the properties of a polysulfone ultrafiltration membrane. Accelerated ageing of the membrane was simulated by soaking it in chlorine solutions and the mechanical properties of the membrane were monitored versus soaking time. An oxidation mechanism is validated which involves the catalytic effect of dissolved metal ions and the inhibitor effect of an antioxidant when these are present in soaking solutions

Distintos aspectos del tributo entre los Yauyos de Chaclla (siglos XV-XVIII)

Fil: Gentile Lafaille, Margarita E.. Museo de La Plata. Universidad Nacional de La Plata; Argentin

Los Yauyos de Chaclla: pueblos y ayllus (siglo XVIII)

Fil: Gentile Lafaille, Margarita E.. Museo de La Plata. Universidad Nacional de La Plata; Argentin

Los espacios jurídicos de las identidades étnicas en el área andina argentina: las tres repúblicas en el siglo XVI

Fil: Gentile Lafaille, Margarita E.. Museo de La Plata. Universidad Nacional de La Plata; Argentin

Uso ceremonial de cabezas humanas en Nasca : una pieza del Museo de Arte de Lima

Fil: Gentile Lafaille, Margarita E.. Museo de La Plata. Universidad Nacional de La Plata; Argentin

Swift development of protective effector functions in naive CD8(+) T cells against malaria liver stages.

We generated T cell receptor transgenic mice specific for the liver stages of the rodent malaria parasite Plasmodium yoelii and studied the early events in the development of in vivo effector functions in antigen-specific CD8(+) T cells. Differently to activated/memory cells, naive CD8(+) T cells are not capable of exerting antiparasitic activity unless previously primed by parasite immunization. While naive cells need to differentiate before achieving effector status, the time required for this process is very short. Indeed, interferon (IFN)-gamma and perforin mRNA are detectable 24 h after immunization and IFN-gamma secretion and cytotoxic activity are detected ex vivo 24 and 48 h after immunization, respectively. In contrast, the proliferation of CD8(+) T cells begins after 24 h and an increase in the total number of antigen-specific cells is detected only after 48 h. Remarkably, a strong CD8(+) T cell-mediated inhibition of parasite development is observed in mice challenged with viable parasites only 24 h after immunization with attenuated parasites. These results indicate that differentiation of naive CD8(+) T cells does not begin only after extensive cell division, rather this process precedes or occurs simultaneously with proliferation

Notas sobre algunas mujeres del Collasuyu (siglos XV al XVIII)

Fil: Gentile Lafaille, Margarita E.. Museo de La Plata. Universidad Nacional de La Plata; Argentin

Maternal-Fetal Immune Tolerance, Block by Block

How difficult is to go from egg to implanted embryo? The evolution of placentation in eutherian mammals created enormous challenges, in particular to the maternal immune system, as the fetus expresses paternal antigens that are capable of triggering immune rejection. Samstein et al. reveal a role for inducible regulatory T cells in the enforcement of maternal-fetal immune tolerance

Los mates pirograbados de la cuenca del Río Doncellas

Fil: Alfaro, Lidia. Fil: Gentile Lafaille, Margarita E.. Academia Nacional de la Historia; Per