Long-Lived Non-Equilibrium Interstitial-Solid-Solutions in Binary Mixtures

We perform particle resolved experimental studies on the heterogeneous crystallisation process of two compo- nent mixtures of hard spheres. The components have a size ratio of 0.39. We compared these with molecular dynamics simulations of homogenous nucleation. We find for both experiments and simulations that the final assemblies are interstitial solid solutions, where the large particles form crystalline close-packed lattices, whereas the small particles occupy random interstitial sites. This interstitial solution resembles that found at equilibrium when the size ratios are 0.3 [Filion et al., Phys. Rev. Lett. 107, 168302 (2011)] and 0.4 [Filion, PhD Thesis, Utrecht University (2011)]. However, unlike these previous studies, for our system sim- ulations showed that the small particles are trapped in the octahedral holes of the ordered structure formed by the large particles, leading to long-lived non-equilibrium structures in the time scales studied and not the equilibrium interstitial solutions found earlier. Interestingly, the percentage of small particles in the crystal formed by the large ones rapidly reaches a maximum of around 14% for most of the packing fractions tested, unlike previous predictions where the occupancy of the interstitial sites increases with the system concentration. Finally, no further hopping of the small particles was observed

Language as purposeful: functional varieties of texts

This volume, "Language as Purposeful: Functional Varieties of Texts", is the third of the first three e-books of a new series entitled, "Functional Grammar Studies for Non-Native Speakers of English", which is contained within the superordinate: "Quaderni del Centro di Studi Linguistico-Culturali (CeSLiC)", a research center in the Department of Modern Foreign Languages of the University of Bologna. The series proposes a metalinguistic description of English grammar in a functional, socio-semiotic perspective and is proving to be an effective teaching/learning resource for improving English literacy in the L2 pedagogic setting. The principal ‘consumers’ of the series are the students of the English Language Studies Program (ELSP) in Bologna’s Faculty of Foreign Languages and Literature, for whom it provides the basic course-book in each of their three years of the first-level degree course. This third volume applies the descriptive model taught in the first two years to the analysis of diverse text-types, and thus at the same time seeks to empower students through an increasing awareness of the typical functions of the English language in a variety of concrete situational and cultural contexts

Exposure to polychlorinated biphenyls and hexachlorobenzene, semen quality and testicular cancer risk

PURPOSE: We carried out a case-control study to investigate the possible role of occupational and environmental exposure to endocrine disruptors in the onset of testicular cancer (TC). METHODS: We evaluated 125 TC patients and 103 controls. Seminal fluid examination and organochlorine analysis were performed in all subjects. Cases and controls were also interviewed using a structured questionnaire to collect demographic information, residence, andrological medical history and dietary information. RESULTS: We found that a higher level of reproductive tract birth defects was associated with a higher risk of TC. With regard to diet, cases reported a higher consumption of milk and dairy products than controls. Overall, there was a statistically significant increase in TC risk in cases with detectable values of total polychlorinated organic compounds against controls (14.4 vs. 1.0 %; p < 0.001). TC patients with detectable levels of organochlorines had lower mean semen parameters than those with undetectable levels, although this difference was not statistically significant. CONCLUSION: The International Agency for Research on Cancer recently included dioxin-like polychlorinated biphenyls (PCBs) in Group 1 of known human carcinogens. Our study confirmed and identified various risk factors for testicular cancer: cryptorchidism, consumption of milk and dairy products, parents' occupation and serum concentration of hexachlorobenzene and PCBs and, for the first time, we showed the correlation between semen quality and the serum concentration of these pollutants