62 research outputs found
High strain rate effects in masonry structures under waterborne debris impacts
Masonry buildings are vulnerable to extreme hydrodynamic events such as floods or tsunamis. Post-disaster surveys have shown that waterborne debris impacts can significantly damage masonry walls during these events. To simulate these actions, the current design or research practice is to compute the force–time diagram of the impact and then use it for dynamic analyses. Standing on the current knowledge, debris impacts are highly impulsive, but it is not clear if such loads are fast enough to activate the high strain rate effects in masonry, i.e. the strain rate dependency of material properties. The present study aims to answer this question, for the first time, following nonlinear Finite Element (FE) simulations. Simulations are conducted on a masonry wall, following a micro-modelling strategy, subjected to water flow and waterborne debris impact under different scenarios. It is found that the strain rates exceed the critical threshold after which strain rate effects are considerable. Such a finding, initially obtained using the minimum design demand for log-type debris imposed by ASCE/SEI 7-22, is further extended to a range of impact force–time diagrams different in impact duration and peak force (corresponding to different debris properties or flow velocity). It is also shown that the impact location (i.e. midspan or close to the boundary) affects the strain rate magnitude because of the changes in the impact stiffness and the activated failure mechanisms. Furthermore, it is found that the dynamic tensile post-elastic behaviour of the materials is the most influencing parameter in the structural response. These results open a new area in the field of assessment and design of masonry structures to waterborne debris and guide the development of future experiments, numerical simulations or design relations
Opportunità di selezione naturale in una comunità alpina dell’Antico Delfinato
Surname analysis in the study of the identities of two communities in the Susa Valley (Turin) in the 18th and 19th centuries
Ft-Ir spectroscopy and microspectroscopy of ancient egyptian embalmed heads from the Museum of Anthropology and Ethnography of the University of Turin
Fourier Transform Infrared (FT-IR) spectroscopy and microspectroscopy were used to gain insight into the state
of preservation of the skin of two Egyptian dynastic embalmed heads (VI-XI Dynasty) and one Predynastic
mummy. The mummies came from the necropoles of Asiut and Gebelein (Upper Egypt), and are curated at the
Museum of Anthropology and Ethnography of the University of Turin. The state of preservation was inferred
from the biochemical composition of the skin, in particular from the secondary structure of the proteins. The
secondary structure of the skin protein was investigated by studying the position and shape of the Amide I
band, analyzed by means of self-deconvolution techniques. The increase in the b-sheet relative amount in the
protein conformation of the mummified tissues with respect to the modern skin, was correlated with aging
processes of collagen and keratins, the most abundant proteins in the skin. The steps of the degradation processes
are hypothesized and described, and the differences in the recorded state of degradation were ascribed
to the diverse mummification procedures undergone by the studied human remains. Other non-skin-derived
features in the IR micro spectra of the embalmed specimens were detected and identified either as embalming
materials or microbial attack traces
Serum steroid profiling by isotopic dilution-liquid chromatography-mass spectrometry: comparison with current immunoassays and reference intervals in healthy adults.
BACKGROUND:
The simultaneous, rapid and reliable measurement of a wide steroid panel is a powerful tool to unravel physiological and pathological hormone status. Clinical laboratories are currently dominated by high-throughput immunoassays, but these methods lack specificity due to cross-reactivity and matrix interferences. We developed and validated an isotopic dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) method for the simultaneous measurement of cortisol, corticosterone, 11deoxycortisol, androstenedione, deoxycorticosterone (DOC), testosterone, 17OHprogesterone, dehydroepiandrosterone (DHEA) and progesterone in serum, and compared it to routine immunoassays employed in our laboratory. We also established adult reference intervals in 416 healthy subjects.
METHODS:
0.9 ml of serum were spiked with labelled internal standards (IS) and extracted on C18 cartridges. Eluate was injected into a two-dimensional LC-system, purified in a perfusion column and separated on a C8 column during a 21 min gradient run. Analytes were revealed by atmospheric pressure chemical ionization (APCI) followed by multiple reaction monitoring (MRM) analysis.
RESULTS:
Of the four immunoassays compared with the ID-LC-MS/MS method, only the results of ElecsysE170 for cortisol, testosterone in males and progesterone>1 ng/ml were in agreement with ID-LC-MS/MS. ElecsysE170 for testosterone in females and progesterone<1 ng/ml, Immulite2000 for androstenedione, DSL-9000 for DHEA and 17OHP Bridge for 17OHprogesterone, respectively, showed poor agreement. Reference intervals and steroid age and fertility related fluctuations were established.
CONCLUSION:
Our ID-LC-MS/MS method proved to be reliable and sensitive in revealing steroid circulating concentrations in adults and in highlighting the limits of routine immunoassays at low concentrations
Biodemographic Structure of an Ancient Population: the Cholera Epidemic of 1837 in Alia (Palermo, Sicily)
Emigrazione temporanea recente e di lungo corso a Giaglione (TO): 1858 e 1861
Migration is a reversible phenomenon that has interested to greater or lesser extent all human communities . Immigration allows not only to enrich the genetic pool of a population but also to import new behavioral patterns that may prove essential in the development and survival of the community. Emigration, despite impoverishing the genetic patrimony at first, may later establish a
future enrichment for the population of origin, provided that emigration has the character of temporality: the individual migrants have the opportunity to form and grow in an environment different from the native one, importing new experiences in the community of origin , possibly
accompanied by a allochthonous partner and thus contributing to the expansion of input genetic flow.
The temporary migration is studied here through the population censuses of Giaglione (TO) in the years of transition from the state of Savoy (1858 ) to the Kingdom of Italy (1861). The family-based documentation is very detailed for both surveys and the censuses also included the "temporarily absents", together with information on their home and work
Sex ratio and individual variability analysis within mountain communities of the western Alps
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