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This study proposes a novel seismic protection strategy that applies and distributes extended KDamper devices (d-EKD) along the height of an existing mid-rise building structure. The performance of the d-EKD is assessed on a set of real earthquake records and is compared to a system with optimally distributed Tuned Mass Dampers (d-TMD). The proposed framework with the d-EKDs manages to outperform the d-TMDs, regardless the number of installed devices, further reducing the structure's dynamic responses by more than5%, using0 times lower total additional masses, rendering it a realistic and compelling alternative for passive seismic protection. [ABSTRACT FROM AUTHOR]

The stochastic response of multi-story buildings isolated by laminated rubber bearing (LRB), lead-rubber bearing (N-Z system), friction pendulum system (FPS), and resilient-friction base isolator (R-FBI) is investigated under the independent multi-hazard scenario of earthquake ground motion (EQGM), wind load (WL), and blast-induced ground motion (BIGM), which are considered as uncertain inputs. A polynomial regression-based Monte Carlo simulation (PRBMCS) is proposed to enable computationally efficient fragility assessment of base-isolated buildings. The suitability of the PRBMCS for stochastic assessment of the base-isolated buildings is compared with the conventional Monte Carlo simulation (MCS), response surface method (RSM) and Cloud analysis. The fragility curves obtained using the PRBMCS are in good agreement with that of the MCS relatively. The study includes: the effects of the characteristic parameters of the four base isolators on the fragility of the base-isolated buildings under the three hazards; influence of the extent of uncertainty in the excitations; and comparison of fragilities of the base-isolated and fixed-base buildings. Notably, the influences of characteristic parameters of the isolators on the fragility of the base-isolated buildings are different under the three hazards. The differences in the stochastic behaviour under the different hazards could have contradictory influences on the selection of isolation parameters. [ABSTRACT FROM AUTHOR]

This study investigates the association between financial strain and psychological distress among middle-aged and older adults, exploring how this association is mediated by sleep problems and moderated by marital status. A subsample of 12,095 adults aged 50 and older was selected from the 2018 National Health Interview Survey. Results showed that financial strain was associated with higher psychological distress, and sleep problems partially mediated this association. Marital status moderated the association between sleep problems and psychological distress, and between financial strain and psychological distress, but not between financial strain and sleep problems. These findings partially support the stress-buffering role of marriage. The study offers valuable insights into the complex relationship between financial strain, sleep problems, marital status, and psychological distress among middle-aged and older adults in the United States, highlighting the need for interventions targeting financial stressors and sleep problems, especially for unmarried individuals, to improve mental health outcomes in this population. [ABSTRACT FROM AUTHOR]

Background/objectives: Patients hospitalized with alcohol withdrawal syndrome (AWS) are typically treated with CIWA-directed benzodiazepines to prevent complications, such as seizures and delirium tremens. Gabapentin is an evidence-based alternative to benzodiazepines in the outpatient setting, but there is limited data for hospitalized patients with AWS. This study compared fixed-dose gabapentin to CIWA-directed benzodiazepines for AWS in the hospital setting. Methods: This open-label, randomized controlled trial enrolled 88 adults from February 1, 2017 to August 16, 2020 with a risk of complicated alcohol withdrawal as defined by the Prediction of Alcohol Withdrawal Severity Scale (PAWSS) ≥4. Patients were randomized within 16 h of admission to either fixed-dose gabapentin taper or continued CIWA-directed benzodiazepine administration. The primary outcome was the length of stay (LOS). Secondary outcomes included seizure, delirium tremens, ICU transfer, and patient-reported symptoms (alcohol cravings, anxiety, sleepiness). Results: LOS was shorter, but not statistically different in the gabapentin group compared to the benzodiazepine group. Because benzodiazepines were received in both gabapentin and benzodiazepine groups before randomization, the mean amount of benzodiazepines received in each group was also not statistically different, although the amount received by the gabapentin group was less than half of that received by the benzodiazepine group (4.3 vs. 10.6 mg, p = 0.146 by per protocol analysis). There were no statistical differences in secondary measures. Conclusions: Fixed-dose gabapentin taper showed similar outcomes compared to CIWA-directed benzodiazepines for the treatment of hospitalized patients with mild/moderate AWS, but the interpretation of the results is limited due to under-enrollment and the use of benzodiazepines in both groups pre-enrollment. Clinical trial registration: NCT03012815. [ABSTRACT FROM AUTHOR]

Analytical framework for probabilistic assessment of dynamical system under base- and mass- excitations with equal input energy is presented with reference to multi-hazard engineering. Closed-form solutions for equivalent undamped and damped dynamical systems under harmonic sinusoidal base- and mass- excitations are obtained. Uncertainties are considered in the excitation frequency and peak amplitude for sinusoidal base excitations, whereas for the mass excitations, the input forcing functions have variations in excitation frequency, mean speed, and fluctuating wind speeds. Dynamic response quantities (acceleration and displacement) are obtained under the suite of stochastic base and mass excitation forces. Structural failure under the independent excitations is determined as joint probability density functions and fragility surfaces. Under equal input energy from such separate dynamic excitations, dissimilar vulnerability is exhibited by the structure when exposed to two independent time-dependent excitations, base-induced earthquake and mass-induced wind forces. Moreover, the uncertainty in the input excitation parameters has significant influence on the probability of failure in the design life of structure under the non-simultaneous excitations. [ABSTRACT FROM AUTHOR]

The present study aims at constructing an assembly of fragility curves which is a tool for probabilistic investigation of seismic responses for a six storey reinforced concrete base-isolated building, excited by near field (NF) and far field (FF) real ground motions, situated in plain terrain. For the sake of comparison, a similar fixed base building has been chosen. The base isolator adopted is a lead rubber bearing and the design parameters are in accordance to UBC-97. Fragility curves are derived using incremental dynamic analysis method. From the probabilistic demand model, maximum inter-storey drift ratio, maximum base shear and maximum top floor acceleration are computed as the damage parameters whose probability of exceedance (Pf) under predefined damage states for different intensities of earthquakes are recorded. The threshold values of intensity measure are estimated by performing linear regression. Fragility function results illustrated that fixed base buildings have a very high probability of failure in case of both NF and FF earthquakes, which is however, reduced by base isolator. Though the vulnerability of the base-isolated building was quite high for NF earthquakes, Pf for FF earthquakes was nearly negligible. [ABSTRACT FROM AUTHOR]

The paper proposes a new approach for optimal design structures equipped with tuned mass dampers (TMDs) with large mass ratios. The approach is based on minimizing the frequency response function (FRF) of displacement response of the structure as well as the acceleration of the TMD that leads to almost equal modal damping ratios in the first and second mode of vibration. Furthermore, two regression equations are proposed to predict the optimum TMD properties. It is concluded that choosing the optimum TMD parameters as suggested in this study provides up to 94% reduction in the maximum FRF of structural displacement. [ABSTRACT FROM AUTHOR]

Closed form expressions for optimum Tuned Mass Damper (TMD) parameters are obtained by equating Eigen values of two modes and there is no need of any trial and error approach as used in earlier studies. For certain values of damping of main system and mass ratio, two sets of optimum parameters exist. For some other range of damping and mass ratio, modes become fully damped. In this range, optimum TMDs do not exist, and this happens for TMDs with large mass. The optimum TMD is shown to be quite robust and gives lesser TMD displacement as compared to optimum TMDs of earlier studies. [ABSTRACT FROM AUTHOR]

Tall buildings are especially prone to damage caused by winds and earthquakes. In practice, only a single hazard is assumed to dominate the design and is adopted for structural verifications. This is also the case when supplemental damping devices such as tuned mass dampers (TMDs) are adopted. Nevertheless, previous research has shown that from a life-cycle cost (LCC) perspective the dominant hazard concept is misleading, and a multi-hazard approach is necessary. This article proposes a methodology for multi-objective optimization-based design of multiple TMDs (MTMDs) attached to tall buildings subjected to both winds and earthquakes. The LCC related to damage on non-structural components is taken as one of the objective functions to join consistently these hazards. The MTMDs initial cost is selected as the second objective function. The results of these multi-objective optimization problems are Pareto fronts of optimized solutions that may be of interest to stakeholders, including non-technical decision makers. A genetic algorithm is adopted as solution strategy. A realistic case study is presented, and the optimization results are compared with classic literature solutions. [ABSTRACT FROM AUTHOR]

The effectiveness of the multi-mode control of seismically excited building installed with distributed multiple tuned mass dampers (d-MTMDs) is investigated by comparing dynamic response with the other controllers, such as passive friction dampers, semi-active dampers, single tuned mass damper (STMD), and multiple tuned mass dampers (MTMDs-all.top), both installed at the top of the building, and arbitrarily distributed MTMDs (ad-MTMDs). It is concluded that the d-MTMDs exhibit improved performance as compared with the STMD, MTMDs-all.top, and ad-MTMDs. The d-MTMDs are also convenient to install owing to the reduced space requirements, being placed at various floors. [ABSTRACT FROM AUTHOR]

Publications reporting techniques and applications of thin layer chromatography (planar chromatography) for the separation, detection, qualitative and quantitative determination, and preparative isolation of pesticides and their metabolites are reviewed for the period from November 1, 2016 to November 1, 2018. Analyses are described for a variety of samples types and pesticide classes. In addition to references on residue analysis, studies such as pesticide chromatographic retention, identification and characterization of natural pesticides (biopesticides), metabolism, bioactivity, degradation, soil mobility, and lipophilicity are covered. A summary and thoughts on future prospects are provided. [ABSTRACT FROM AUTHOR]

It is well known that the use of passive energy dissipation devices such as friction dampers reduces the dynamic response of structures subjected to earthquakes. However, the parameters of each damper as well as the best position of these devices in the structure remain difficult to determine. Although articles on optimum design of tuned mass dampers and viscous dampers have been published, there is a lack of studies on the optimization of friction dampers. In previous contributions, the authors proposed a method for optimum design of this kind of damper. The proposed method is very useful; however, the computational time required is high. Thus, in this article, a new methodology for the simultaneous optimization of placement and forces of friction dampers is proposed. As this new method is developed in the frequency domain, the computational time is considerably reduced. For this purpose, the search group algorithm, recently developed by the authors, is employed, which is able to deal with optimization problems involving mixed discrete and continuous variables. For illustrative purposes, a six-storey shear building is analysed. Forces and positions of friction dampers are the design variables, while the objective function is to minimize the root mean square displacement at the top of the building. The results showed the excellent performance of the proposed method, reducing the root mean square displacement by more than 82%, with only three friction dampers and in a relatively short computational time. [ABSTRACT FROM AUTHOR]

Spices are the dried parts of aromatic plants, excepting the leaves, usually used for flavoring, seasoning and imparting aroma in foods. They contain many classes of valuable compounds, which can also exert different biological activities, such as antioxidant and antimicrobial activity. Since spices contain important bioconstituents, they are often adulterated in economical purposes, not only by the botanical and geographical origin, but also by adding or subtracting of different substances which affect in a negative manner their quality. The aim of this paper is to overview the TLC methods used in the analysis of spices, in order to evaluate their composition and biological activities, and also to detect the adulteration. [ABSTRACT FROM AUTHOR]

MultiferroicxBi3.25La0.75Ti3O12-(1-x)CoFe2O4composite thin films withx= 0.5, 0.6, and 0.7 were deposited on Pt/Ti/SiO2/Si(100) substrates by a chemical solution deposition process. The well-defined ferroelectric loops are observed. ThePrvalues are 8.89, 11.97, and 13.78 μC/cm2under the condition of about 350 kV/cm electric field for the composite films withx= 0.5, 0.6, and 0.7 respectively. The composite films exhibit typical magnetic hysteresis loops, as well as remnant magnetizations. Magnetoelectric effect which is dependent onHbiasis observed. The composite films exhibit both good ferroelectric and magnetic properties at room temperature, as well as a magnetoelectric effect. [ABSTRACT FROM AUTHOR]

In the present work, using a hybrid sol-gel route, we have synthesized CoFe2O4/Pb0.85La0.15TiO3 (CFO/PLT15) composite thin films on platinized silicon substrates. The synthesized films are characterized in terms of phase formation behavior, microstructure, magnetic and electrical properties. At room temperature, these composite films exhibit both polarization as well as magnetization hysteresis loops. As compared to pure PLT thin films, the PLT-CFO composite films exhibit lower saturation (∼35 μC/cm2) and remnant polarizations (∼10 μC/cm2) with reduced coercive fields. [ABSTRACT FROM AUTHOR]