a b s t r a c tDifferent sufficient conditions for stochastic comparisons between random vectors have been described in the literature. In particular, conditions for the comparison of random vectors having the same copula, i.e., the same dependence structure, may be found in Müller and Scarsini (2001). Here we provide conditions for the comparison, in the usual stochastic order sense and in other weaker stochastic orders, of two time transformed exponential bivariate lifetimes having different copulas. Some examples of applications are provided too.

The optimization of conditions to promote the stemness of pluripotent cells in vitro is instrumental for their use in advanced therapies. We show here that exposure of human iPSCs and human ESCs to low concentrations of the chemical NO donor DETA/NO leads to stabilization of hypoxia-inducible factors (HIF-1α and HIF-2α) under normoxia, with this effect being dependent on diminished Pro 402 hydroxylation and decreased degradation by the proteasome. Moreover, the master genes of pluripotency, NANOG and OCT-4, were upregulated. NO also induces a shift in the metabolic profile of PSCs, with an increased expression of hypoxia response genes in glycolysis. Furthermore, a reduction in the mitochondrial membrane potential with lower oxygen consumption and increased expression of mitochondrial fusion regulators, such as DRP1, was observed. The results reported here indicate that NO mimics hypoxia response in human PSCs and enhances their stemness properties when cultured under normoxic conditions.

Negative aging and stochastic comparisons of residual lifetimes in multivariate frailty models / MULERO J; PELLEREY F.; RODRIGUEZ-GRIGNOLO R. AbstractConsider two random vectors X 1 and X 2 whose distributions are defined according to the multivariate frailty approach, and let X k,t = [X k − t|X k > t], k = 1, 2, be the corresponding vectors of residual lifetimes at t = (t 1 , . . . , t n ), t i ∈ R, i = 1, . . . , n. Conditions for multivariate stochastic comparisons of random vectors described by the frailty approach have been recently presented in Misra, Gupta and Gupta (2009), "Stochastic comparisons of multivariate frailty models", Journal of Statistical Planning and Inference, 139, 2084-2090. Here we prosecute their study, providing sufficient conditions for the stochastic comparison X 1,t ≤ st X 2,t , where t is an arbitrary vector in R n . Sufficient conditions for the stochastic comparisons X i,t ≤ st X i,t+v , where t is as above and v is a vector with non-negative components, are presented too.

The dissemination of research in cultural heritage preservation to the public is a task that needs new models and expressions, to capture the attention of the public and the assessment of results. With this purpose, a new educational experience in Parque de las Ciencias (Science Park of Granada, Spain) was developed. The science window titled Hidden Face of Cultural Heritage (ScW-CH) was an exhibition to show the risks (hazards + vulnerability) associated to different artworks and materials of our cultural heritage (CH). ScW-CH was led by the researchers themselves, in collaboration with museum specialists, in order to develop a new model that makes their research accessible to all demographics. An innovative methodology based into simulating a showcase, was designed to study hazards and vulnerability in CH. Therefore, the montage contained materials, equipment, information sheets, and guides to accompany visitors as storytellers. The aim of the exhibition, was for the visitors to understand the risks posed to our monuments and artworks from a scientific point of view, and to raise awareness about the care that we should give to our CH. The ScW-CH was held for 6 months and visited by 8226 visitors. During the exhibition, a survey about the opinion of visitors was carried out to study the impact of the designed new model and assess the results of the experience. The collected data was analysed by the Statistical Package for the Social Sciences (version 22.0). Visitors usually presented a medium-high initial interest about visiting this exhibition, and a medium-low level of knowledge of this subject. Thanks to ScW-CH, 92% of visitors showed a very high learning level after the experience. The ratio of interest and learning in the ScW-CH in relationship with the level of study showed that secondary school pupils had the highest degree of interest and learning.

No abstract