Fatigue assessment of components subjected to random loads is a challenging task both due to the variability in amplitude and frequency of the loads and for the computational times required to perform classical time domain fatigue analysis. The frequency domain approach to fatigue life assessment offers a solution by utilizing the power spectral density of the random load, requiring minimal computational effort. However, frequency domain methods are limited to stationary Gaussian signals, while real-world loads often exhibit non-Gaussian characteristics.
View Article and Find Full Text PDFIn this study, site-specific natural background levels (NBLs) were determined for 18 elements (Al, As, Be, Cd, Co, Cu, Cr, Fe, Hg, K, Mn, Mo, Ni, Pb, Tl, U, V, and Zn) in two sediment cores collected offshore the Bagnoli-Coroglio brownfield site (Gulf of Pozzuoli, southern Italy) to accurately assess the degree of contamination and the historical trends in Heavy Metals (HMs) enrichment. This objective was pursued taking in account the high temporal and spatial variability of the geochemical properties of the area due to the local geothermal activity. Moreover, the temporal variation of Polycyclic Aromatic Hydrocarbons (PAHs) was investigated.
View Article and Find Full Text PDFThis study aims to explore the reliability of flood warning forecasts based on deep learning models, in particular Long-Short Term Memory (LSTM) architecture. We also wish to verify the applicability of flood event predictions for a river with flood events lasting only a few hours, with the aid of hydrometric control stations. This methodology allows for the creation of a system able to identify flood events with acceptable errors within several hours' notice.
View Article and Find Full Text PDFBaseline study of natural (Be, Pb, Ra, Th, Ra, K) and anthropogenic (Cs) radionuclides was carried out in two cores collected from Sabaki River estuary (Kenya, Indian Ocean). There was no exponential decrease of excess Pb down the cores, which did not allow dating and determination of heavy metal pollution history. The use of Cs as a time marker was not possible due to its low fallout rates in East Africa.
View Article and Find Full Text PDFIsotopic composition of mercury (Hg) in marine organisms and sediment cores was used to identify sources and reconstruct historical trends of contamination in the coastal-marine area of Rosignano Solvay (Italy), affected by Hg pollution from a chlor-alkali plant on the near land. Sediments show a wide range of Hg concentration and Hg isotope signatures. Particularly, coupled Hg concentration and δHg values trace inputs from different sources.
View Article and Find Full Text PDFLaboratories from 14 countries (with different levels of expertise in radionuclide measurements and Pb dating) participated in an interlaboratory comparison exercise (ILC) related to the application of Pb sediment dating technique within the framework of the IAEA Coordinated Research Project. The laboratories were provided with samples from a composite sediment core and were required to provide massic activities of several radionuclides and an age versus depth model from the obtained results, using the most suitable Pb dating model. Massic concentrations of Zn and Cu were also determined to be used for chronology validation.
View Article and Find Full Text PDFIn continental margins, canyons appear to act as natural conduits of sediments and organic matter from the shelf to deep basins, providing an efficient physical pathway for transport and accumulation of particles with their associated land-produced contaminants. However, these mechanisms have not been yet sufficiently explored by geochemical markers. The continental slope of the south Sardinia has been used as a natural laboratory for investigating mechanisms and times of transfer dynamics of contaminants from land to sea and from shelf to deep sea through an articulated system of submarine canyons.
View Article and Find Full Text PDFAlthough the thymus is a primary lymphoid organ, its function is compromised by an age-induced loss of resident epithelial cells, which results in reduced naïve T cell output. This has important implications for immune recovery in aged and elderly patients following damage from cytoablative therapies. As thymic architecture plays a crucial role in naïve T cell development, a tissue specific scaffold that provides essential supporting matrix may assist in stem cell-based thymus regeneration to recreate complex organoids.
View Article and Find Full Text PDFAlthough forkhead-box n1 (Foxn1) is a critical thymic epithelial cell regulator in thymus organogenesis, its association with epithelial differentiation and homeostasis in the postnatal and aged thymic microenvironment remains conflicting. Consequently, we have generated a Foxn1 knock-in mouse model that allows for refined investigation of the aging thymic epithelium. This reporter line differs from those previously published in that concomitant expression of enhanced green fluorescent protein enables live cell sorting of Foxn1 cell populations.
View Article and Find Full Text PDFJ Environ Radioact
December 2012
Following the Fukushima power plants accident on the 11th March 2011, the radioactivity monitoring programme at the Italian ENEA research centres was activated in order to detect the possible new input of radionuclides through atmospheric transport and precipitation. Measurements of (131)I and (134,137)Cs were carried out on atmospheric particulate, atmospheric deposition, seawater and mussels and sheep milk. In the daily samples of air particulate, (131)I was detectable between March 28 and April 12, with extremely low concentrations (<1 mBq m(-3); the detection limit for (131)I was ~0.
View Article and Find Full Text PDFDifferent pelagic areas of the Mediterranean Sea have been investigated in order to quantify physical and biological mixing processes in deep sea sediments. Herein, results of eleven sediment cores sampled at different deep areas (> 2000 m) of the Western and Eastern Mediterranean Sea are presented. ²¹⁰Pb(xs) and ¹³⁷Cs vertical profiles, together with ¹⁴C dating, are used to identify the main processes characterising the different areas and, finally, controlling mixing depths (SML) and bioturbation coefficients (D(b)).
View Article and Find Full Text PDFParagonimiasis (human infections with the lung fluke Paragonimus westermani) is an important public health problem in parts of Southeast Asia and China. Paragonamiasis has rarely been reported from North America as a zoonosis caused by Paragonimus kellicotti. Paragonimus species have complex life cycles that require 2 intermediate hosts, namely, snails and crustaceans (ie, crabs or crayfish).
View Article and Find Full Text PDFHospital-acquired infections have profound social, economic, and personal costs to patients in the intensive care unit (ICU). Numerous risk factors, such as poor nutrition and hyperglycemia, directly involve patients. Meanwhile, hand hygiene, environmental cleaning, and appropriate hospital staffing can impact ICU infection rates.
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