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l riscaldamento globale riguarda tutta la comunità mondiale, quest’anno tutti gli Stati si sono riuniti a Glasgow (COP26) per affrontare il problema che è molto grave per tutti e soprattutto per le nuove generazioni. Spesso è utilizzato il termine geologico Antropocene per indicare l’impatto dell’azione umana sulla Terra. È necessario capire come si può inquadrare questa sfida per il genere umano dal punto di vista etico; se il termine Antropocene sia una modalità di comunicazione ad effetto o sia scientificamente fondato; come si sia giunti a doversi porre questa domanda; quali scenari si pongono davanti alla specie umana.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of loose glass tesserae from the Northwest Quarter of Gerasa/Jerash has enhanced our understanding of the dynamics regulating the production and circulation of glass tesserae in second- to eighth-centuries ce Jordan and the diachronic development of mosaics at the site. The identification of Levantine and Egyptian compositions (Roman-Mn, Levantine I, HIMT, Foy 2.1) proves the continuous production of mosaics from the second to the seventh centuries. The Levantine I tesserae were made by the recycling and colouring of glass cullet. The gilded tesserae, in contrast, were all of an Egyptian base glass, likely illustrating the import of finished tesserae.

Background: Although prevalent in prokaryotes, horizontal gene transfer (HGT) is rarer in multicellular eukaryotes. Bdelloid rotifers are microscopic animals that contain a higher proportion of horizontally transferred, non-metazoan genes in their genomes than typical of animals. It has been hypothesized that bdelloids incorporate foreign DNA when they repair their chromosomes following double-strand breaks caused by desiccation. HGT might thereby contribute to species divergence and adaptation, as in prokaryotes. If so, we expect that species should differ in their complement of foreign genes, rather than sharing the same set of foreign genes inherited from a common ancestor. Furthermore, there should be more foreign genes in species that desiccate more frequently. We tested these hypotheses by surveying HGT in four congeneric species of bdelloids from different habitats: two from permanent aquatic habitats and two from temporary aquatic habitats that desiccate regularly.\ud \ud Results: Transcriptomes of all four species contain many genes with a closer match to non-metazoan genes than to metazoan genes. Whole genome sequencing of one species confirmed the presence of these foreign genes in the genome. Nearly half of foreign genes are shared between all four species and an outgroup from another family, but many hundreds are unique to particular species, which indicates that HGT is ongoing. Using a dated phylogeny, we estimate an average of 12.8 gains versus 2.0 losses of foreign genes per million years. Consistent with the desiccation hypothesis, the level of HGT is higher in the species that experience regular desiccation events than those that do not. However, HGT still contributed hundreds of foreign genes to the species from permanently aquatic habitats. Foreign genes were mainly enzymes with various annotated functions that include catabolism of complex polysaccharides and stress responses. We found evidence of differential loss of ancestral foreign genes previously associated with desiccation protection in the two non-desiccating species.\ud \ud Conclusions: Nearly half of foreign genes were acquired before the divergence of bdelloid families over 60 Mya. Nonetheless, HGT is ongoing in bdelloids and has contributed to putative functional differences among species. Variation among our study species is consistent with the hypothesis that desiccating habitats promote HGT.\ud

In antiquity, beach sand was one of the main raw materials for glass-making and for the production of other vitreous materials, like Egyptian blue and faience. During the 1st century AD, glass and pigments manufacturing industry was active along the Gulf of Naples, Italy, where we sampled four littoral sands. Samples were analyzed with different techniques: chemical analysis was performed by means of X-Ray Fluorescence (XRF) and mineralogical analyses with X-Ray Powder Diffraction (XRPD) and Raman Spectroscopy. The complete sintering to melting thermal behaviour of the four sands was studied by heating microscopy or hot-stage microscope (HSM) equipped with an high resolution camera capable to collect sample profile during heating. The effect of the grain size on the sintering curves, which were automatically elaborated by specimen profile transformation, was also investigated. Finally, some deductions about the granulometry effect and the presence of alkaline and alkaline-earth oxides on sintering and melting behaviour were drawn. All the four sands were found suitable for highly sintered manufacts rather than glasses, to reach complete amorphous materials the addition of fluxes was necessary.

Resource-based view research plays a prominent role in strategic management studies. In this paper we investigate the relativistic interpretation of the "scarcity" concept, the appropriability of complementary resources, the measurability of the contribution that a specific resource brings to the overall value of the firm. The theoretical issues have been made context specific trying to show (a) how a not-scarce complementary resource like movie theatres can help build value for the distributor, mainly through the creation of reputation for the subsequent TV broadcasting; (b) that this resource can be appropriated from different companies; (c) that companies can develop different kinds of interfirm relationships in order to control complementary resources; (d) that reliable and valid parameters can be provided to measure the value of resources and the related degree of control from the distributors. Supporting empirical evidence is provided and implications for managing complementary resources are discussed. © 1998 Kluwer Academic Publishers.