Dynamic characterization of a system with degradation: A masonry wall

Characterization of the dynamic behavior of linear systems is exhaustively described with a single frequency response curve (frc). For nonlinear systems, which tend to depend on load amplitude, at least one frc for each excitation intensity is required to detect the main characteristics of the dynamic response. Nonlinear systems, more commonly dealt with in the literature, are invariant with respect to the deformation history and, thus, frcs obtained with increasing and decreasing driving frequency coincide, apart from the frequency range with coexistent solutions. This is not so for many real systems which suffer from their past, often exhibiting degradation of their mechanical properties. Here the focus is on the effects of damage on the dynamic signature of systems. The response of a masonry wall, representative of systems with a degrading restoring force, is analyzed under harmonic excitation. A refined finite element model is used to represent the typical degradation that occurs in masonry and its reliability is proved by comparing numerical results and experimental outcomes from shaking table tests. Particular attention is paid to the wall frcs, emphasizing the influence of the deformation history on the curves characteristics and their role in the dynamic characterization of a system with degradation

Development and distribution of the non-indigenous Pacific oyster (Crassostrea gigas) in the Dutch Wadden Sea

Pacific oysters (Crassostrea gigas) were first observed in the Dutch Wadden Sea near Texel in 1983. The population increased slowly in the beginning but grew exponentially from the mid-1990s onwards, although now some stabilisation seems to be occurring. They occur on a variety of substrates such as mussel beds (Mytilus edulis), shell banks, dikes and poles. After initial settlement spat may fall on older individuals and congregate to dense clumps and subsequently form reefs. Individual Pacific oysters grow 3–4 cm long in their first year and 2–3 cm in their second year. Many mussel beds (Mytilus edulis) are slowly taken over by Pacific oysters, but there are also several reports of mussel spat settling on Pacific oyster reefs. This might in the end result in combined reefs. Successful Pacific oyster spat fall seems to be related to high summer temperatures, but also after mild summers much spat can be found on old (Pacific oyster) shells. Predation is of limited importance. Mortality factors are unknown, but every now and then unexplained mass mortality occurs. The gradual spread of the Pacific oyster in the Dutch Wadden Sea is documented in the first instance based on historical and anecdotal information. At the start of the more in-depth investigation in 2002, Pacific oysters of all size classes were already present near Texel. Near Ameland the development could be followed from the first observed settlement. On dense reefs each square metre may contain more than 500 adult Pacific oysters, weighing more than 100 kg per m² fresh weigh

Lightning performance evaluation of Italian 150 kV sub-transmission lines

A significant majority of overhead transmission lines' (OHLs) outages is due to backflashovers caused by direct lightning strikes: the realistic assessment of the lightning performance is thus an important task. The paper presents the analysis of the lightning performance of an existing 150kVItalian OHL, namely, its backflashover rate (BFOR), carried out by means of anATP-EMTP-based Monte Carlo procedure. Among other features, the procedure makes use of a simplified pi-circuit for line towers' grounding system, allowing a very accurate reproduction of transient behaviours at a very low computational cost. Tower grounding design modifications, aimed at improving the OHL lightning performance, are also proposed and discussed

Some extended Pareto Type I distributions

Probability distributions are essential in data modeling. Introduction of parameter(s) into existing probability distributions is a method of extending or generalizing distributions to produce more flexible distributions and for better fit to data. The Pareto type 1 distribution (PT1) is a right skewed continuous distribution originally used in description of wealth and income but also used for modeling other right skewed data. To add flexibility, Pareto type 1 distribution was extended by introducing parameter(s) into its probability distribution to accommodate more types of data. Some functions of the extended Pareto type 1 distributions were derived using five parameter induction methods. Flexibility of extended distributions was demonstrated through comparisons of density and hazard function shapes of some of the extended distributions with those of the PT1. Further study on properties of non-existing extended Pareto Type I distributions and real-life applications are recommended

Alexithymia, impulsiveness, and psychopathology in Nonsuicidal self-injured adolescents

Introduction: Nonsuicidal self-injury (NSSI) is a multifaceted phenomenon and a major health issue among adolescents. A better understanding of self-injury comorbidities is crucial to improve our ability to assess, treat, and prevent NSSI. Purpose: This study aimed at analyzing some of the psychobehavioral correlates of NSSI: psychological problems, alexithymia, impulsiveness, and sociorelational aspects. Patients and methods: This was a case-control study. The clinical sample (n=33) included adolescents attending our unit for NSSI and other issues; the controls (n=79) were high-school students. Data were collected using six questionnaires: Youth Self-Report, Barratt\u2019s Impulsiveness Scale, Toronto Alexithymia Scale, Children\u2019s Depression Inventory, Symptom Checklist-90-R, and Child Behavior Checklist. Results: Cases scored significantly higher in all questionnaires. Habitual self-injurers scored higher on impulsiveness and alexithymia. The gesture\u2019s repetition seems relevant to the global clinical picture: habitual self-injurers appear more likely to seek help from the sociosanitary services. We found a difference between the self-injurers\u2019 and their parents\u2019 awareness of the disorder. Conclusion: Habitual self-injurers show signs of having difficulty with assessing the consequences of their actions (nonplanning impulsiveness) and the inability to manage their feelings. Given the significantly higher scores found for cases than for controls on all the psychopathological scales, NSSI can be seen as a cross-category psychiatric disorder, supporting the Diagnostic and Statistical Manual of Mental Disorders decision to include it as a pathological entity in its own right

A multi-methodological study of the (K,Ca)-variety of the zeolite merlinoite

A multi-methodological study of the (K,Ca)-variety of the zeolite merlinoite from Fosso Attici, Sacrofano, Italy was carried out on the basis of electron microprobe analysis in wavelength dispersive mode, singlecrystal X-ray diffraction (at 100 K), Raman and infrared spectroscopy. The chemical formula of the merlinoite from Fosso Attici is (Na0.37K5.69)\u3a3=6.06(Mg0.01Ca1.93Ba0.40)\u3a3=2.34(Fe3+0.02Al10.55Si21.38)\u3a3=31.9O64\u38719.6H2O, compatible with the ideal chemical formula K6Ca2[Al10Si22O64]\u38720H2O. Anisotropic structure refinements confirmed the symmetry and the framework model previously reported (space group Immm, a = 14.066(5),b = 14.111(5), c = 9.943(3) \uc5 at 100 K). Refinement converged with four cationic sites and sixH2Osites; refined bond distances of the framework tetrahedra suggest a highly disordered Si/ Al-distribution. The Raman spectrum of merlinoite (collected between 100 and 4000 cm 121) is dominated by a doublet of bands between 496\u2013422 cm 121, assigned to tetrahedral T\u2013O\u2013T symmetric bending modes. T\u2013O\u2013T antisymmetric stretching is also observed; stretching and bending modes of the H2O molecules are only clearly visiblewhen using a blue laser. The single-crystal near-infrared spectrum shows a very weak band at 6823 cm 121, assigned to the first overtone of the O\u2013H stretching mode, and a band at 5209 cm 121, due to the combination of H2O stretching and bendingmodes.Avery broad and convoluted absorption, extending from 3700 to 3000 cm 121 occurs in the H2O stretching region, while the \u3bd2 bending mode of H2O is found at 1649 cm 121. The powder midinfrared spectrum of merlinoite between 400\u20131300 cm 121 is dominated by tetrahedral T\u2013O\u2013T symmetric and antisymmetric stretches. Raman and Fourier-transform infrared spectroscopy spectra of merlinoite and phillipsite provide a quick identification tool for these zeolites, which are often confused due to their close similarity

An acetylation-mono-ubiquitination switch on lysine 120 of H2B.

Post-translational modifications (PTMs) of histones are crucial for transcriptional control, defining positive and negative chromatin territories. A switch of opposing functional significance between acetylation and methylation occurs on many residues. Lysine 120 of H2B is modified by two PTMs: ubiquitination, which is required for further trans-tail H3 methylations and elongation, and acetylation, whose role is less clear. ChIP-Seq with MNase I-treated chromatin indicates that H2BK120ac is present on nucleosomes immediately surrounding the TSS of transcribed or poised units, but not in core promoters. In kinetic ChIP analysis of ER-stress inducible genes, H2BK120ac precedes activation and H2B-ub deposition. Using in vitro acetylation assays, pharmacologic inhibition and RNAi, we established that KAT3 is responsible for H2BK120ac. Interestingly, the global levels of H2B-ub decreased in KAT3-inactivated cells. However, RNF20 recruitment was not impaired by KAT3-inactivation. Our data point at acetylation of Lysine 120 of H2B as an early mark of poised or active state and establish a temporal sequence between acetylation and mono-ubiquitination of this H2B residue