Assessment of the effect of seismic sequences on steel X-CBF for industrial buildings

This work concerns about the study of the effect of the seismic sequences on steel mono-storey industrial buildings equipped with X-CBFs, with the aim to evaluate a code change to adequately consider this issue. Indeed, current technical regulations (CEN, 2004; MIT, 2018) do not take into account this phenomenon, thus the structure are designed only to withstand a single main-shock, without considering the possible accumulation of damage due to the after-shocks. In this work it is instead shown how this effect has to be properly considered and evaluated. First, a mono-storey industrial building is analysed as preliminary case study. Fragility curves are built for both sequences and single main events, thus obtaining an important comparison. Then the study focuses on a single X-CBF, validated through an experimental test from literature. The calibrated system is subjected to both seismic sequences and corresponding mainshocks. Analyses are carried out also by varying brace profiles. The results show a significant influence of the seismic sequences on the increase of the ductility request of the structure. Therefore, with the aim to properly represent the effect of the sequences, it is considered necessary to require a reduction of the available behavior factor, providing a precautionary estimate. This operation wants to give a first preliminary estimate of the increase of the seismic risk only on the seismic vulnerability side of this kind of structures

Fragility curves for reinforced concrete frames characterised by different regularity

This paper presents a comparison between fragility curves developed for regular and non-regular reinforced frames. Three 3D reinforced concrete multi-story frames characterised by different regularity are analysed. These fragility curves are developed through the “Cloud Analysis“ procedure, which evaluates the structural response via Non-Linear Time History Analysis (NLTHA). Both maximum inter-story drift and maximum chord-rotation demand/capacity ratio are used as Engineering Demand Parameters, in which the chord-rotation capacity is calculated according to the Italian Code. To fully develop the fragility curves, both structure-independent and structure-dependent scalar intensity measures are selected among the most referred in practice and literature. This work shows the influence of regularity on the damage levels of the three buildings. Furthermore, it shows the uncertainties caused by the selection criteria for EDP thresholds, which are necessary for a correct representation of the Limit State

Facteurs de risque lors de la conduite d'un projet de mise en place d'un dispositif de veille anticipative dans plusieurs organismes du secteur public

Le présent article s'intéresse aux facteurs de risque susceptibles d'advenir lors de la conduite de projets de mise en place d'un dispositif de veille anticipative stratégique. Sur la base d'une recherche action/intervention au sein de plusieurs organismes du secteur public, les chercheurs ont confronté, plusieurs des facteurs déjà identifiés dans des études antérieures concernant les risques des projets de SI et de veille à ceux rencontrés lors de leur intervention. L'objectif de cette confrontation est d'une part l'identification de facteurs de risques des projets de veille identiques à ceux des projets de SI et d'autre part, l'identification de facteurs de risques spécifiques aux projets de veille. L'intérêt de l'article d'un point de vu théorique est d'avoir fait émerger quatre hypothèses de nouveaux facteurs de risque qui sont autant de pistes de recherche. Il s'agit du mode de communication en face à face, du soutien du " middle management ", du choix du moment de mise en place du projet et du choix du chef de projet. D'un point de vu managérial, cette recherche permet de construire un début de connaissances actionnables permettant de faire de recommandations fondées à un chef de projet de veille démarrant sa tâche dans un tel contexte.Projet de SI, Veille anticipative stratégique, facteur de risque, secteur public, recherche action/intervention

Survey on non-linear cyclic responses of Unreinforced Masonry buildings by means of commercial finite-element codes

This work presents a comparison about the nonlinear cyclic response of unreinforced masonry structures obtained by using commercial calculation codes and on the base of the type of modeling approaches currently available. In particular, several elastoplastic modeling methodologies are considered, representative of a good part of the state of the art for this type of construction: mechanical-based concentrated plasticity macro-element (Tremuri), macro-element with diffuse fiber-based plasticity for flexure and concentrated springs for shear (SeismoStruct) and macro-element with phenomenological-based concentrated plasticity (NextFEM Designer). The purpose of the present research is to evaluate the ability of the different codes to represent the proper hysteretic response of masonry structures. To this aim, several experimental tests from literature are analyzed and compared; two different masonry panels, characterized by different resistant mechanisms, and an entire perforated wall have been studied through nonlinear cyclic static analyses. The reported comparison, mainly focused on the numerical cyclic behaviour exhibited by each computer program, is conducted on the basis of the path of the cycles obtained and on the amount of dissipated energy

Multi-scenario Physics-Based Seismic Hazard Assessment of Cultural Heritage Sites

For relevant engineering purposes a viable alternative to standard estimates of seismic hazard is represented by the use of physics-based ground shaking scenarios. The scenarios are characterized in terms of magnitude, distance and faulting style, taking into account the complexity of the kinematic source rupturing process. In fact, ground-shaking scenarios modelled before the occurrence of an earthquake can be of extreme value in any seismic risk study, in particular in sites with priceless cultural heritage. In those places the effect of low occurrence rate—high consequences events can lead to invaluable losses, therefore an accurate evaluation of the expected ground motions is desirable. To this purpose, a web application, with a friendly graphic user interface, has been developed for multi-scenario physics-based seismic zoning and microzoning (considering site effects). Computational examples at different space and detail scales are presented, focussing on historical sites, such as the Dahshur pyramids, the Madrasa of the Princess Tatar al-Higaziya, Saint Catherine's Monastery in Egypt. For all the cases, the acceleration time histories, generated with the knowledge of the physical properties of the earthquake source and of the medium travelled by the seismic waves, can be used by engineers as seismic input for the vulnerability assessment

Evaluation of the colorimetric tetrazolium assay for the cytotoxicity testing a commercial vanilla flavouring

The tetrazolium colorimetric assay (MTT-assay) has been used to evaluate the cytotoxicity of a vanilla flavouring found on the market. It was characterised by the use of 1,2-propylene glycol and glycerol as diluents and by the presence of vanillin, heliotropine and the corresponding 1,2-propylene and glycerol acetals. The method developed by Mosmann (J. Immunol. Methods 65, 55\u201363-1983) was used with some modifications. The same assay was applied to the diluent 1,2-propylene glycol in order to verify its possible influence on the toxic effect. This technique proved useful for preliminary screening useful to evidence doubts relating to the safety of flavouring preparations

GC/MS-MID Determination of Safrole in Soft Drinks

Safrole [1,3-benzodioxole, 5-(2-propenyl)-] is a limited substance according to the CE Directives N. 88/388 and 91/71 concerning \u201cflavourings for use in foodstuffs and to source materials for their production\u201d. At today the GC analytical methods proposed for the quantitative determination of safrole are critical as far as concerning reproducibility, recovery values and detection limits. This note describes an improved analytical method to quantify safrole in \u201csoft\u201d drinks. Average recoveries of safrole from samples spiked at levels from 30.0 to 80.0 microg/L ranged from 80 to 93% with good reproducibility (RSD=2.7 at 30.0 microg/Ll). Limits of detection (LOD) and quantification (LOQ) were 10.0 microg/L and 30.0 microg/L respectively. The proposed method is also suitable for routine analysis

Mobilized Peripheral Blood Stem Cells Versus Unstimulated Bone Marrow As a Graft Source for T-Cell-Replete Haploidentical Donor Transplantation Using Post-Transplant Cyclophosphamide.

Purpose T-cell-replete HLA-haploidentical donor hematopoietic transplantation using post-transplant cyclophosphamide was originally described using bone marrow (BM). With increasing use of mobilized peripheral blood (PB), we compared transplant outcomes after PB and BM transplants. Patients and Methods A total of 681 patients with hematologic malignancy who underwent transplantation in the United States between 2009 and 2014 received BM (n = 481) or PB (n = 190) grafts. Cox regression models were built to examine differences in transplant outcomes by graft type, adjusting for patient, disease, and transplant characteristics. Results Hematopoietic recovery was similar after transplantation of BM and PB (28-day neutrophil recovery, 88% v 93%, P = .07; 100-day platelet recovery, 88% v 85%, P = .33). Risks of grade 2 to 4 acute (hazard ratio [HR], 0.45; P \u3c .001) and chronic (HR, 0.35; P \u3c .001) graft-versus-host disease were lower with transplantation of BM compared with PB. There were no significant differences in overall survival by graft type (HR, 0.99; P = .98), with rates of 54% and 57% at 2 years after transplantation of BM and PB, respectively. There were no differences in nonrelapse mortality risks (HR, 0.92; P = .74) but relapse risks were higher after transplantation of BM (HR, 1.49; P = .009). Additional exploration confirmed that the higher relapse risks after transplantation of BM were limited to patients with leukemia (HR, 1.73; P = .002) and not lymphoma (HR, 0.87; P = .64). Conclusion PB and BM grafts are suitable for haploidentical transplantation with the post-transplant cyclophosphamide approach but with differing patterns of treatment failure. Although, to our knowledge, this is the most comprehensive comparison, these findings must be validated in a randomized prospective comparison with adequate follow-up

Is Corporate Social Responsibility an Agency Problem? Evidence from CEO Turnovers

We empirically examine two competing claims: first, if a firm’s Corporate Social Responsibility (CSR) activity is driven by its CEO’s private rent extraction (i.e. an agency problem), firms with higher CSR ratings are poorly governed and their managers are less likely to be dismissed for poor financial performance. In contrast, if CSR reflects owners’ preferences, CEOs of firms with higher CSR ratings are more likely to be removed in light of poor financial performance. We find that CEO turnover-financial performance sensitivity increases in firm CSR scores during the last years of both the outgoing CEO as well as his predecessor. Further, firm CSR ratings do not change following CEO turnover suggesting that CSR ratings are a firm characteristic. Our findings are consistent with the view that CSR is driven by shareholder preferences

Engineering yield and rate of reductive biotransformation in Escherichia coli by partial cyclization of the pentose phosphate pathway and PTS-independent glucose transport

Optimization of yields and productivities in reductive whole-cell biotransformations is an important issue for the industrial application of such processes. In a recent study with Escherichia coli, we analyzed the reduction of the prochiral β-ketoester methyl acetoacetate by an R-specific alcohol dehydrogenase (ADH) to the chiral hydroxy ester (R)-methyl 3-hydroxybutyrate (MHB) using glucose as substrate for the generation of NADPH. Deletion of the phosphofructokinase gene pfkA almost doubled the yield to 4.8 mol MHB per mole of glucose, and it was assumed that this effect was due to a partial cyclization of the pentose phosphate pathway (PPP). Here, this partial cyclization was confirmed by 13C metabolic flux analysis, which revealed a negative net flux from glucose 6-phosphate to fructose 6-phosphate catalyzed by phosphoglucose isomerase. For further process optimization, the genes encoding the glucose facilitator (glf) and glucokinase (glk) of Zymomonas mobilis were overexpressed in recombinant E. coli strains carrying ADH and deletions of either pgi (phosphoglucose isomerase), or pfkA, or pfkA plus pfkB. In all cases, the glucose uptake rate was increased (30–47%), and for strains Δpgi and ΔpfkA also, the specific MHB production rate was increased by 15% and 20%, respectively. The yield of the latter two strains slightly dropped by 11% and 6%, but was still 73% and 132% higher compared to the reference strain with intact pgi and pfkA genes and expressing glf and glk. Thus, metabolic engineering strategies are presented for improving yield and rate of reductive redox biocatalysis by partial cyclization of the PPP and by increasing glucose uptake, respectively