Scaling approach to tight-binding transport in realistic graphene devices:the case of transverse magnetic focusing

Ultraclean graphene sheets encapsulated between hexagonal boron nitride crystals host two-dimensional electron systems in which low-temperature transport is solely limited by the sample size. We revisit the theoretical problem of carrying out microscopic calculations of nonlocal ballistic transport in such micron-scale devices. By employing the Landauer-Büttiker scattering theory, we propose a scaling approach to tight-binding nonlocal transport in realistic graphene devices. We test our numerical method against experimental data on transverse magnetic focusing (TMF), a textbook example of nonlocal ballistic transport in the presence of a transverse magnetic field. This comparison enables a clear physical interpretation of all the observed features of the TMF signal, including its oscillating sign

The relationship between group identification and satisfaction with life in a cross-cultural community sample

A variety of studies have shown that group identification (a sense of belonging to one’s social group, coupled with a sense of commonality with the group’s members) is linked to high levels of satisfaction with life (SWL). The aim of the present study was to support and extend this literature by: i) investigating the link between group identification and SWL with a large cross-cultural community sample; ii) examining whether the relationship is moderated by nationality; and iii) considering whether SWL is enhanced by possessing multiple group identifications simultaneously. Utilizing data from Wave 1 of the Health in Groups project, 3,829 participants from both Scotland and Italy completed a questionnaire assessing their identification with their family, their local community, and a group of their choice, as well as their level of SWL. Higher identification with each group predicted higher SWL. Nationality was a marginal moderator of the relationship between family identification and SWL, with the relationship being stronger for Italian participants than for Scottish participants. There was also an additive effect of group identification, with a positive relationship between the number of groups with which participants identified and their SWL. These effects were obtained even after controlling for gender, age, employment status, nationality, and extent of contact with each group. The implications for healthcare professionals and their patients are discussed

Numerical and experimental dynamic studies on historical masonry structures

This paper presents the results of the numerical and experimental dynamic analysis carried out on two historical masonry structures, the Viaduct of Vara in the marble cave in Carrara and the bell tower of St. Niccola’s church in Pisa. The first structure is a five span arch bridge built at the end of 19th century, while the second is considered a masterpiece of the Romanesque art and was built in the Middle Ages, about 1200 AD. After numerical finite element analysis experimental dynamic tests were carried out both on the bridge and the bell tower. The studies focus on the use of wavelet transform techniques for extracting modal parameters from the time-histories registered during the tests performed. The achieved results show that wavelet analysis performs better than Fourier analysis for dynamic identification of stiff and massive structures such those examined. Finally, the comparison between numerical and experimental results allows the calibration of the numerical models

Dynamic Characterization of a Five Spans Historical Masonry Archbridge

This paper presents the studies carried out on a five spans masonry arch bridge, the Viaduct of Vara, inside the marble caves close to Carrara. The bridge was strengthened in recent time due to the failure of a pier. Two sets of dynamic tests were performed, the first before the strengthening, the second after the strengthening was carried out. A finite element model of the structure was made for preliminary studies. Dynamic tests were necessary to validate numerical results. After describing the way the tests were performed in situ and the instrumentation used for collecting the data, a comparison is made between numerical and experimental modal parameters (before and after the strengthening) of the structure. Signal processing techniques used for modal parameters extraction focus on the use of wavelet transforms, which are a very powerful tool in case the signals are non stationary and with a low signal to noise ratio

High testosterone levels of ovarian origin affect adrenal steroidogenesis?

Androgens of ovarian origin have been suggested to affect adrenal enzymatic activity. To investigate this possibility, the 17-hydroxyprogesterone (17-OH P) and cortisol (F) responses to an ACTH stimulation test (0.25 mg iv, bolus) were evaluated in 10 normal women and in 39 hyperandrogenic women with normal (14 subjects) or high (25 subjects) testosterone (T) levels. The 17-OH P release and the ratio between 17-OH P and F release in response to the ACTH stimulation test were significantly higher (P < 0.05) in hyperandrogenic women with high T levels than in normal subjects. Eight hyperandrogenic women with high T received intranasal GnRH agonist (Buserelin, 1200 μg/day) for 4 weeks, and the 17-OH P and F release in response to the ACTH stimulation was reassessed after agonist treatment. At the end of GnRH agonist administration the mean circulating lev sis of T were significantly reduced (P < 0.05). The F response to the ACTH test was not modified by pretreatment with the GnRH agonist. The 17-OH P response to the ACTH stimulation test after the GnRH agonist was unchanged in comparison w.th control tests, as well as the ratio between 17-OH P and F responses to the ACTH test. These data do not seem to confirm, as previously suggested, that high T levels of ovarian origin affect adrenal steroidogenesis. © 1991 by The Endocrine Society