The Gap Between Linear Elasticity and the Variational Limit of Finite Elasticity in Pure Traction Problems

A limit elastic energy for the pure traction problem is derived from re-scaled nonlinear energies of a hyperelastic material body subject to an equilibrated force field. We prove that the strains of minimizing sequences associated to re-scaled nonlinear energies weakly converge, up to subsequences, to the strains of minimizers of a limit energy, provided an additional compatibility condition is fulfilled by the force field. The limit energy is different from the classical energy of linear elasticity; nevertheless, the compatibility condition entails the coincidence of related minima and minimizers. A strong violation of this condition provides a limit energy which is unbounded from below, while a mild violation may produce unboundedness of strains and a limit energy which has infinitely many extra minimizers which are not minimizers of standard linear elastic energy. A consequence of this analysis is that a rigorous validation of linear elasticity fails for compressive force fields that infringe up on such a compatibility condition

Where does brain neural activation in aesthetic responses to visual art occur? Meta-analytic evidence from neuroimaging studies

Here we aimed at finding the neural correlates of the general aspect of visual aesthetic experience (VAE) and those more strictly correlated with the content of the artworks. We applied a general activation likelihood estimation (ALE) meta-analysis to 47 fMRI experiments described in 14 published studies. We also performed four separate ALE analyses in order to identify the neural substrates of reactions to specific categories of artworks, namely portraits, representation of real-world-visual-scenes, abstract paintings, and body sculptures. The general ALE revealed that VAE relies on a bilateral network of areas, and the individual ALE analyses revealed different maximal activation for the artworks' categories as function of their content. Specifically, different content-dependent areas of the ventral visual stream are involved in VAE, but a few additional brain areas are involved as well. Thus, aesthetic-related neural responses to art recruit widely distributed networks in both hemispheres including content-dependent brain areas of the ventral visual stream. Together, the results suggest that aesthetic responses are not independent of sensory, perceptual, and cognitive processe

Characterization of a disease-associated mutation affecting a putative splicing regulatory element in intron 6b of the cystic fibrosis transmembrane conductance regulator (CFTR) gene

Cystic fibrosis (CF) is a common recessive disorder caused by >1600 mutations in the CF transmembrane conductance regulator (CFTR) gene. About 13% of CFTR mutations are classified as “splicing mutations,” but for almost 40% of these, their role in affecting the pre-mRNA splicing of the gene is not yet defined. In this work, we describe a new splicing mutation detected in three unrelated Italian CF patients. By DNA analyses and mRNA studies, we identified the c.1002–1110_1113delTAAG mutation localized in intron 6b of the CFTR gene. At the mRNA level, this mutation creates an aberrant inclusion of a sequence of 101 nucleotides between exons 6b and 7. This sequence corresponds to a portion of intron 6b and resembles a cryptic exon because it is characterized by an upstream ag and a downstream gt sequence, which are most probably recognized as 5′- and 3′-splice sites by the spliceosome. Through functional analysis of this splicing defect, we show that this mutation abolishes the interaction of the splicing regulatory protein heterogeneous nuclear ribonucleoprotein A2/B1 with an intronic splicing regulatory element and creates a new recognition motif for the SRp75 splicing factor, causing activation of the cryptic exon. Our results show that the c.1002–1110_1113delTAAG mutation creates a new intronic splicing regulatory element in intron 6b of the CFTR gene exclusively recognized by SRp75

Occurrence of heavy metals (Hg, Cd, and Pb) and polychlorinated biphenyls in salted anchovies.

The most popular brands of salted anchovies (Engraulis encrasicolus) from the Mediterranean Sea and Atlantic Ocean were purchased from several Italian supermarkets and grocery stores. Heavy metal (Hg, Cd, and Pb) and polychlorinated biphenyl (PCB) levels were determined and assessed by comparing the concentrations in these samples with the maximum permissible limits set by the European Union (Reg EC 629/2008 and Reg EC 1881/2006 [Off. J. Eur. Union L 173:3-9 and 364:5-24, respectively]). The Hg and Cd levels were higher than those of Pb in all samples examined. For Hg and Pb, the concentrations recorded in this study were below the authorized limits, while an appreciable percentage of samples from both locations (Mediterranean Sea, 35%, and Atlantic Ocean, 25%) showed Cd levels exceeding the threshold recommended for human consumption. Concerning PCBs, the results of principal component analysis showed that samples from the two different marine areas appeared to be discriminate, with Mediterranean anchovies more contaminated than the others, in spite of their lower lipid content. However, anchovy samples from both locations had dioxinlike-PCB levels (Mediterranean Sea, 0.011 pg World Health Organization toxic equivalency [WHO-TEQ] g(-1), wet weight, and Atlantic Ocean, 0.007 pg WHO-TEQ g(-1), wet weight) that were below the WHO-TEQ maximum concentration set by European regulation. The results of this study will help in generating data needed for the assessment of heavy metal and PCB intake from this food

Multidimensional news quality: A comparison of crowdsourcing and nichesourcing

In the age of fake news and of filter bubbles, assessing the quality of information is a compelling issue: it is important for users to understand the quality of the information they consume online. We report on our experiment aimed at understanding if workers from the crowd can be a suitable alternative to

Unconventional ratiometric-enhanced optical sensing of oxygen by mixed-phase TiO2

We show that mixed-phase titanium dioxide (TiO2) can be effectively employed as an unconventional, inorganic, dual-emitting and ratiometric optical sensor of O2. Simultaneous availability of rutile and anatase TiO2 PL and their peculiar anti-correlated PL responses to O2 allow using their ratio as measurement parameter associated to O2 concentration, leading to an experimental responsivity being by construction larger than the one obtainable for single-phase PL detection. A proof of this concept in given, showing a two-fold enhancement of the optical responsivity provided by the ratiometric approach. Besides the peculiar ratiometric-enhanced responsivity, other characteristics of mixed phase TiO2 can be envisaged as favorable for O2 optical probing, namely: a) low production costs, b) absence of heterogeneous components, c) self-supporting properties. These characteristics encourage experimenting its use for applications requiring high indicator quantities at competitive price, possibly also tackling the need to develop supporting matrixes that carry the luminescent probes and avoiding issues related to the use of different components for ratiometric sensing.Comment: 12 pages, 5 figure

Fair Innings? The Utilitarian and Prioritarian Value of Risk Reduction over a Whole Lifetime

The social value of risk reduction (SVRR) is the marginal social value of reducing an individual’s fatality risk, as measured by some social welfare function (SWF). This Article investigates SVRR, using a lifetime utility model in which individuals are differentiated by age, lifetime income profile, and lifetime risk profile. We consider both the utilitarian SWF and a “prioritarian” SWF, which applies a strictly increasing and strictly concave transformation to individual utility. We show that the prioritarian SVRR provides a rigorous basis in economic theory for the “fair innings” concept, proposed in the public health literature: as between an older individual and a similarly situated younger individual (one with the same income and risk profile), a risk reduction for the younger individual is accorded greater social weight even if the gains to expected lifetime utility are equal. The comparative statics of prioritarian and utilitarian SVRRs with respect to age, and to (past, present, and future) income and baseline survival probability, are significantly different from the conventional value per statistical life (VSL). Our empirical simulation based upon the U.S. population survival curve and income distribution shows that prioritarian SVRRs with a moderate degree of concavity in the transformation function conform to widely held views regarding lifesaving policies: the young should take priority but income should make no difference