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The collapse and damage of large number of buildings during the November 26, 2019 (Mw 6,4) Albania earthquake caused 51 fatalities and injuries to at least 910 people. Most of collapsed or heavily damaged buildings were RC frame buildings. Although RC frame system is considered as very ductile seismic force-resisting system, its behaviour during earthquake highly depends on: (1) regularity in plan and elevation, and (2) global and local ductility. Based on the authors' visit to the earthquake-affected area on behalf of the Serbian Association of Earthquake Engineering and observations of collapsed and damaged buildings, it was concluded that among main reasons for underperformance of these flexible systems were inadequate analysis of interaction between infill walls and RC frames and reinforcement detailing of RC members.

Scientists from different disciplines at ETH Zurich are developing a dynamic, harmonised, and user-centred earthquake risk framework for Switzerland, relying on a continuously evolving earthquake catalogue generated by the Swiss Seismological Service (SED) using the national seismic networks. This framework uses all available information to assess seismic risk at various stages and facilitates widespread dissemination and communication of the resulting information. Earthquake risk products and services include operational earthquake (loss) forecasting (OE(L)F), earthquake early warning (EEW), ShakeMaps, rapid impact assessment (RIA), structural health monitoring (SHM), and recovery and rebuilding efforts (RRE). Standardisation of products and workflows across various applications is essential for achieving broad adoption, universal recognition, and maximum synergies. In the Swiss dynamic earthquake risk framework, the harmonisation of products into seamless solutions that access the same databases, workflows, and software is a crucial component. A user-centred approach utilising quantitative and qualitative social science tools like online surveys and focus groups is a significant innovation featured in all products and services. Here we report on the key considerations and developments of the framework and its components. This paper may serve as a reference guide for other countries wishing to establish similar services for seismic risk reduction. [ABSTRACT FROM AUTHOR]

Introduction: Stroke in young people has a major socioeconomic impact, since up to 30% of young patients may die or have permanent sequelae with expected longer survival than older patients. Aim: The aim is to investigate the efficacy and safety of intravenous thrombolysis in the young adults with acute ischemic stroke (AIS) comparing to elderly patients. Material and Methods: A total of 403 patients suffering from AIS treated with intravenous thrombolysis, were divided by age into two groups: patients aged 18 to 45 (n = 59) and patients older than 45 years (n = 344). The functional outcome, assessed by modified Rankin scale (mRS), was used as a measure of therapy efficacy, and the presence of symptomatic intracerebral hemorrhage (sICH) and mortality as a measure of thrombolysis safety. The follow-up period was 3 months after stroke onset. Results: There were no difference between two groups of patients in excellent functional outcome (mRS ≤ 1) (p = 0.149) and good functional outcome (mRS ≤ 2) (p = 0.156), while the rate of death was significantly lower in the group of younger patients (18-45 years 5.2% vs. > 45 years 17.0% , p = 0.019). Also, there was no statistically significant difference in the presence and type of sICH between these 2 groups of patients. Conclusion: There is no significant difference in good and excellent functional outcome, as well as the incidence of sICH in young adult patients with AIS treated with intravenous thrombolysis, compared to the older patients. The fatal outcome is lower in the group of younger AIS patients.

The paper presents nonlinear analysis of square CFT columns using distributed plasticity fiber elements. Behaviour of CFT columns is nonlinear and it is necessary to include different nonlinear effects into the numerical model in order to simulate their behaviour properly. Model proposed in this work considers: nonlinear behaviour of concrete and steel using nonlinear stress-strain models, confinement effect and geometrical nonlinearities. Tests exposed to static loading with different slenderness, different D/t ratio (where D is the total dimension of a cross section and t is the thickness of steel tube) and different loading conditions are analyzed. Stress-strain models that best approximate the behaviour of CFT columns are determined from a detailed parametric study. The proposed numerical model is validated by comparing numerical with experimental results available in the literature.

Disaster resilient civil infrastructure systems are essential for disaster resilient communities. Measuring the resilience of these systems is the first step towards their improvement. This, however, is not easy: civil infrastructure systems are highly complex, operate in different ways, and are affected differently in different disasters. Adding to the complexity are the dynamic interdependencies among components of such systems, that change as the community is recovering. The Re-CoDeS framework for quantifying disaster resilience measures the lack of resilience of a system (e.g., a community) as the amount of the system's unmet demand for a considered resource or service over the resilience assessment interval. This paper presents a novel demand/supply-based method to consider dynamic component interdependencies by extending the Re-CoDeS framework: whenever the demand of a component is not met by the currently available supply capacity of the system, that component ceases to operate and its supply capacity decreases. The proposed iRe-CoDeS framework is demonstrated on a virtual community served by three interdependent civil infrastructure systems producing five types of resources and services. Step-by-step instructions for defining a community model within the iRe-CoDeS framework are presented to facilitate the use of the proposed framework. [ABSTRACT FROM AUTHOR]

Scientists at ETH Zurich from different disciplines are developing a dynamic, harmonised and user-centred earthquake risk framework for Switzerland, relying on a continuously evolving earthquake catalogue generated by the SED using the national seismic networks. This framework uses all available information to assess seismic risk at various stages and facilitates widespread dissemination and communication of the resulting information. Earthquake risk products and services include Operational Earthquake (Loss) Forecasting (OE[L]F), Earthquake Early Warning (EEW), ShakeMaps, Rapid Impact Assessment (RIA), Structural Health Monitoring (SHM), as well as Recovery and Rebuilding Efforts (RRE). Standardisation of products and workflows across various applications is essential for achieving broad adoption, universal recognition, and maximum synergies. In the Swiss dynamic earthquake risk framework, the harmonisation of products into seamless solutions that access the same databases, workflows, and software is a crucial component to ensure standardisation. A user-centred approach utilising quantitative and qualitative social science tools like online surveys and focus groups is a significant innovation featured in all products and services. Here we report on the key considerations and developments of the framework and its components. [ABSTRACT FROM AUTHOR]

The kinetics and mechanism of isothermal crystal growth of K2TiGe3O9 from a glass of the same stoichiometric composition were studied. The crystal growth rate U = 1 x 10-11-1.27 x 10-10 m s-1 was experimentally determined in the temperature interval of t = 540-600°C. In the range of high undercooling, Δt=435-375°C, spherical crystals growing at (374 ± 19) kJ mol-1 was observed.

Experience from previous earthquakes shows that electrical substations are the most vulnerable components within the power transmission system. Thus, their disaster resilience is essential for providing electric power to communities in earthquake‐prone regions. In this study, a quantitative framework was proposed to assess the seismic resilience of electrical substations. The functionality of a substation was quantified using its maximum allowable transmission capacity that integrates the substation topology, redundancy level, line capacity, and power balance. The network model of the substation was developed to investigate how component damage affects substation's functionality. Substation's recovery was simulated as a time‐stepping process, in which at each time step the substation's ability to provide transmission capacity was conditioned on the functionality state of its components, whose recovery depends on the availability of repair crews and spare parts. The uncertainty of the resilience assessment was quantified by considering the uncertainty in the component‐level vulnerability and recoverability. The impacts of components' robustness, repair resource constraints, and post‐earthquake recovery scheduling on substation resilience were investigated by modifying components' seismic fragility curves, available recovery resources, and repair priorities. A case study was conducted on a real‐world 220/110 kV step‐down substation, and a parametric analysis was carried out to investigate the effect of various seismic resilience improvement strategies to demonstrate the applicability of the proposed framework in seismic disaster risk reduction and management. [ABSTRACT FROM AUTHOR]

Non-metallic mineral fillers strongly influence the characteristics and quality of paper. "Visočica" limestone and "Virpazar" dolomite were used to prepare paper samples in this study. The characteristics of such paper samples produced on a laboratory paper machine are presented. The used fillers and paper pulp were also characterized. The following paper characteristics were investigated: gramature, thickness, softness, air permeability, resistance to tearing and stretching, paper ash and retention. The experiments were performed in order to compare the influence of the physico-chemical and structural qualities of the examined carbonate type fillers on the paper properties. The results of the investigation indicated the technological reasons for using these non-metallic mineral raw materials as fillers in the paper industry regarding the mechanical paper characteristics, as well as other properties.

The results of an investigation of the chemical and thermal characteristics of glass-ceramic enamels, derived from the Li2O-Na2O-Al2O3-TiO2-SiO2 system obtained by employing the methods of mathematical experiment planning, are presented in this paper. Adequate mathematical models, showing the dependence of the chemical and thermal stability on the chemical composition of enamel systems, after different thermal treatment procedures, were obtained. Based on the testing carried out, it was concluded that in the obtained glass-ceramic enamels the chemical resistance is decreased, but at the same time, the thermal stability is increased, relative to reference coatings.

The results of research on the conditions for obtaining model glass-ceramic enamels, derived from the basic Li2O-Na2O-Al2O3-TiO2-SiO2 system, by varying the initial composition and thermal treatment conditions, are presented in this paper. Segregation of the crystal phases in the glassy-matrix was carried out during subsequent thermal treatment. The formation of different crystal phases was evidenced through the results of differential-thermal analysis and X-ray powder diffraction analysis.

In this paper the effect of the addition of Li2O on the crystallization behavior of PbO-B2O3-ZnO glass was investigated by the differential thermal analysis (DTA) and X-ray powder diffraction (XRPD) methods. The crystallization ability, as well as the crystalline phases which develop during devitrification of the glass were examined. The results of DTA and XRPD analysis showed that the addition of Li2O varies the sequence of the crystallization as well as the phase composition of the crystalline phase. The glasses with Li2O crystallize at a lower temperature (360°C) with 4Li2O.4ZnO.3B2O3 as the major crystalline phase. The base PbO-B2O3-ZnO glass crystallizes at 480°C with PbO.2ZnO.B2O2 as the major crystalline phase.