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A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame (PCF) structures with “dry” connections in terms of their low damage and rapid recovery. The framework integrates various uncertainties in the seismic hazard, fragility, capacity, demand, loss functions, and post-earthquake recovery. In this study, the PCF structures are distinguished from ordinary reinforced concrete frame (RCF) structures by characterizing multiple limit states for the PCF based on its unique damage mechanisms. Accordingly, probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit states. In the seismic resilience analysis, a step-wise recovery model is proposed to idealize the functionality recovery process, with separate considerations of the repair and non-repair events. The recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss estimation. As such, contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely circumvented. The proposed framework is demonstrated through a comparative study between two “dry” connected PCFs and one RCF designed as alternative structural systems for a prototype building. The results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the RCF. Particularly, the PCF equipped with energy dissipation devices at the “dry” connections largely reduces the expected economic loss, downtime, and resilience loss by 29%, 56%, and 60%, respectively, compared to the RCF.

In seismology and earthquake engineering, it is fundamental to identify and characterize the pulse-like features in pulse-type ground motions. To capture the pulses that dominate structural responses, this study establishes congruence and shift relationships between response spectrum surfaces. A similarity search between spectrum surfaces, supplemented with a similarity search in time series, has been applied to characterize the pulse-like features in pulse-type ground motions. The identified pulses are tested in predicting the rocking consequences of slender rectangular blocks under the original ground motions. Generally, the prediction is promising for the majority of the ground motions where the dominant pulse is correctly identified.

Insufficient sleep is a growing global health concern, linked to various adverse health outcomes. While the effects of PM2.5 on health are well-documented, the impact of PM1 exposure, particularly its interaction effects with temperature on sleep quality, remains less understood. This nationwide study included 1,100,294 records from 4,783 individuals nationwide using wearable devices to collect sleep data across China. Daily PM1 exposure levels were derived from the China High Air Pollutants (CHAP) dataset, and hourly nighttime temperatures were obtained from the ERA5-Land dataset. Associations between PM1 exposure and sleep duration were evaluated using linear mixed-effect models. An interquartile range (IQR) increase in PM1 concentration significantly altered sleep duration: total sleep increased by 1.51 min (95% CI: 0.52 to 2.50), light sleep increased by 2.87 min (95% CI: 1.97 to 3.76), and deep sleep decreased by 1.28 min (95% CI: −1.81 to −0.75). Nighttime temperatures were negatively associated with sleep duration. High nighttime temperatures amplified the adverse impact of PM1 on deep sleep reduction, while slightly mitigating its effect on light sleep. Stronger associations were observed in individuals aged 45 years and older, those with lower BMI, urban residents, and daily smokers. Although individual sleep duration changes appear modest, the cumulative impact of PM1 on sleep structure, especially in vulnerable populations, poses significant public health risks in physiological restoration. Our research emphasizes the urgency of integrating nighttime temperatures and PM1 emissions monitoring into strategies, particularly safeguarding sleep quality in vulnerable populations, including older adults, individuals with lower BMI, urban dwellers, and smokers.

Three 1/3-scale precast segmental bridge columns, manufactured with ultrahigh-performance fiber-reinforced concrete (UHPFRC) incorporating river sand and coarse aggregate, were tested under cyclic loading. Energy dissipation (ED) bars, embedded in ultrahigh-performance concrete (UHPC) grout, maintained continuous across segment joints and unbonded at the bottom joint. Self-centering prestressing force was provided by unbonded posttensioning (PT) tendons. The research parameters included PT force level and the amount of ED bars. Test results showed that all the specimens exhibited no less than 8% drift capacities, which were remarked with the first fracture of ED bars. No obvious cracking and limited UHPFRC spalling were observed. Both PT force level and the amount of ED bars have notable effects on stiffness, lateral strength, and ductility. Increased PT force may improve ductility with the total axial loading ratio less than 0.08. All PT tendons were elastic and no yield or rupturing was found, but the stress loss was significant. The equivalent unbonded length can be evaluated with 0.007dbfy for ED bars embedded in UHPC grout. The rotation of the bottom joint dominated lateral deformation and the contribution of joint sliding can be neglected. The contribution λED of ED bars to lateral strength should be no more than 25% to maintain self-centering capacity.

Uses of real-world data to evaluate vaccine safety and effectiveness are often challenged by unmeasured confounding. The study aimed to review the application of methods to address unmeasured confounding in observational vaccine safety and effectiveness research. We conducted a systematic review (PROSPERO: CRD42024519882), and searched PubMed, Web of Science, Embase, and Scopus for epidemiological studies investigating influenza and COVID-19 vaccines as exposures, and respiratory and cardiovascular diseases as outcomes, published between January 1, 2017, and December 31, 2023. Data on study design and statistical analyses were extracted from eligible articles. A total of 913 studies were included, of which 42 (4.6%, 42/913) accounted for unmeasured confounding through statistical correction (31.0%, 13/42) or confounding detection or quantification (78.6%, 33/42). Negative control was employed in 24 (57.1%, 24/42) studies—2 (8.3%, 2/24) for confounding correction and 22 (91.7%, 22/24) for confounding detection or quantification—followed by E-value (31.0%, 13/42), prior event rate ratio (11.9%, 5/42), regression discontinuity design (7.1%, 3/42), instrumental variable (4.8%, 2/42), and difference-in-differences (2.4%, 1/42). A total of 871 (95.4%, 871/913) studies did not address unmeasured confounding, but 38.9% (355/913) reported it as study limitation. Unmeasured confounding in real-world vaccine safety and effectiveness studies remains underexplored. Current research primarily employed confounding detection or quantification, notably negative control and E-value, which did not yield adjusted effect estimates. While some studies used correction methods like instrumental variable, regression discontinuity design, and negative control, challenges arise from the stringent assumptions. Future efforts should prioritize developing valid methodologies to mitigate unmeasured confounding. [Display omitted] •Unmeasured confounding in vaccine safety and effectiveness studies remains seldom addressed.•Negative control is the most frequently employed method for unmeasured confounding.•Current studies primarily address unmeasured confounding by confounding detection or quantification, for example, negative control and E-value.•Identified methods for confounding correction include negative control, PERR, IV, RDD, and DiD.•The review stresses the need to develop valid methodologies for unmeasured confounding.

BACKGROUND: Occupational heat-related illness (OHI) is a health threat to workers that can be fatal in severe cases. Effective and feasible measures are urgently needed to prevent OHI. OBJECTIVES: We evaluated the effectiveness of a multifaceted intervention, TEMP, in reducing the OHI risk among outdoor workers in the power grid industry. METHODS: A cluster randomized controlled trial was conducted with power grid outdoor workers in Southern China from 4 July 2022 to 28 August 2022. Work groups were randomly allocated (1:1) to the intervention or control groups. The multifaceted intervention TEMP comprised mobile application (app)-based education training (T), personal protective equipment [PPE (E)], OHI risk monitoring (M), and educational posters (P). Four follow-ups were conducted every 2 wk after the trial began. The primary outcome was the OHI incidence, and the secondary outcome was PPE usage. The app usage was considered as the compliance of intervention in the intervention group. The primary analysis used was intention-to-treat analysis. Multilevel analyses using random effects logistic regression models were performed to compare the odds of OHI between the two groups, adjusted for individual-level (education and work position) and work-related (including water intake when feeling thirsty, cooling measures, and poor sleep before work) covariates. RESULTS: Of 528 participants, 422 (79.92%) were males, and the mean [+ or -] SD age was 36:36 [+ or -] 8:18 y. The primary outcome, OHI incidence, was 1.80% in the intervention group and 4.82% in the control group at the end of the whole follow-up. OHI mainly occurred between 1100 and 1500 hours, with nausea, significantly increased heart rate, and oliguria being the top three reported OHI symptoms. Compared with the control group, the adjusted odds ratios between the intervention group and control group were 0.73 [95% confidence interval (CI): 0.30, 1.76] in the first follow-up wave, with 0.38 (95% CI: 0.15, 0.97), 0.29 (95% CI: 0.08, 1.05), and 0.39 (95% CI: 0.13, 1.19) in the following three follow-up waves, respectively. The intervention also significantly improved PPE usage in the intervention group. DISCUSSIONS: This multifaceted intervention reduced the OHI risk among outdoor workers in the power grid industry. However, further research is needed to design a more flexible intervention strategy and evaluate its effectiveness in a larger population.

Occupational heat-related illness (OHI) is a health threat to workers that can be fatal in severe cases. Effective and feasible measures are urgently needed to prevent OHI. We evaluated the effectiveness of a multifaceted intervention, TEMP, in reducing the OHI risk among outdoor workers in the power grid industry. A cluster randomized controlled trial was conducted with power grid outdoor workers in Southern China from 4 July 2022 to 28 August 2022. Work groups were randomly allocated (1:1) to the intervention or control groups. The multifaceted intervention TEMP comprised mobile application (app)-based education training (T), personal protective equipment [PPE (E)], OHI risk monitoring (M), and educational posters (P). Four follow-ups were conducted every 2 wk after the trial began. The primary outcome was the OHI incidence, and the secondary outcome was PPE usage. The app usage was considered as the compliance of intervention in the intervention group. The primary analysis used was intention-to-treat analysis. Multilevel analyses using random effects logistic regression models were performed to compare the odds of OHI between the two groups, adjusted for individual-level (education and work position) and work-related (including water intake when feeling thirsty, cooling measures, and poor sleep before work) covariates. Of 528 participants, 422 (79.92%) were males, and the age was y. The primary outcome, OHI incidence, was 1.80% in the intervention group and 4.82% in the control group at the end of the whole follow-up. OHI mainly occurred between 1100 and 1500 hours, with nausea, significantly increased heart rate, and oliguria being the top three reported OHI symptoms. Compared with the control group, the adjusted odds ratios between the intervention group and control group were 0.73 [95% confidence interval (CI): 0.30, 1.76] in the first follow-up wave, with 0.38 (95% CI: 0.15, 0.97), 0.29 (95% CI: 0.08, 1.05), and 0.39 (95% CI: 0.13, 1.19) in the following three follow-up waves, respectively. The intervention also significantly improved PPE usage in the intervention group. This multifaceted intervention reduced the OHI risk among outdoor workers in the power grid industry. However, further research is needed to design a more flexible intervention strategy and evaluate its effectiveness in a larger population. https://doi.org/10.1289/EHP14172.

Insufficient sleep is a growing global health concern, linked to various adverse health outcomes. While the effects of PM 2.5 on health are well-documented, the impact of PM 1 exposure, particularly its interaction effects with temperature on sleep quality, remains less understood. This nationwide study included 1,100,294 records from 4,783 individuals nationwide using wearable devices to collect sleep data across China. Daily PM 1 exposure levels were derived from the China High Air Pollutants (CHAP) dataset, and hourly nighttime temperatures were obtained from the ERA5-Land dataset. Associations between PM 1 exposure and sleep duration were evaluated using linear mixed-effect models. An interquartile range (IQR) increase in PM 1 concentration significantly altered sleep duration: total sleep increased by 1.51 min (95% CI: 0.52 to 2.50), light sleep increased by 2.87 min (95% CI: 1.97 to 3.76), and deep sleep decreased by 1.28 min (95% CI: −1.81 to −0.75). Nighttime temperatures were negatively associated with sleep duration. High nighttime temperatures amplified the adverse impact of PM 1 on deep sleep reduction, while slightly mitigating its effect on light sleep. Stronger associations were observed in individuals aged 45 years and older, those with lower BMI, urban residents, and daily smokers. Although individual sleep duration changes appear modest, the cumulative impact of PM 1 on sleep structure, especially in vulnerable populations, poses significant public health risks in physiological restoration. Our research emphasizes the urgency of integrating nighttime temperatures and PM 1 emissions monitoring into strategies, particularly safeguarding sleep quality in vulnerable populations, including older adults, individuals with lower BMI, urban dwellers, and smokers.

In order to systematically assess the complex soil-structure interaction (SSI) effects on the seismic responses of shear wall structures, this dissertation deals with several critical and inter-related topics under the framework of performance-based earthquake engineering. Firstly, the study develops improved pulse representations for earthquake ground motions that govern the peak structural responses. Based on rigorous dimensional analysis, the dimensionless H-response spectra are derived for both linear and bilinear SDOF systems. They are shown to be congruent with the corresponding (dimensional) response spectrum in bi-logarithmic plotting. This leads to a novel approach to identify pulse parameters that match simultaneously the kinematic characteristics and the response spectrum of the original ground motion. The improved pulse representations can potentially be used as the intensity measures of earthquake ground motions. Secondly, the SSI effects of lumped soil-foundation-structure interacting (SFSI) systems are investigated through the dimensional analysis with pulse motions as input. The dimensionless terms that govern the interactive behavior of SFSI systems are derived. The SSI effects are related explicitly and directly to the characteristics of input ground motions and the properties of SFSI systems. The conditions under which the SSI effects amplify or reduce the structural responses are also identified. Subsequently, dynamic responses of strip foundations bonded on linear or nonlinear soil half-space are investigated using the finite element method. The dynamic foundation responses are found to depend on the amplitude and frequency of input motion, foundation geometry, and soil properties. The energy dissipation through radiation damping for nonlinear soil case is reduced and can be quantified with two alternative factors related to the yielding of soil medium. Finally, the SSI effects are evaluated for a realistic shear wall structure using the probabilistic seismic demand analysis where the nonlinear hysteretic behavior of shear walls and foundations are accurately modeled. Either the inelastic spectral displacement or the pulse representation is adopted as the intensity measure of input ground motions. The damage probability of the shear wall generally decreases when the SSI effects are considered for this case study.

The efficiencies of perovskite solar cells (PSCs) are now reaching such consistently high levels that scalable manufacturing at low cost is becoming critical. However, this remains challenging due to the expensive hole-transporting materials usually employed, and difficulties associated with the scalable deposition of other functional layers. By simplifying the device architecture, hole-transport-layer-free PSCs with improved photovoltaic performance are fabricated via a scalable doctor-blading process. Molecular doping of halide perovskite films improved the conductivity of the films and their electronic contact with the conductive substrate, resulting in a reduced series resistance. It facilitates the extraction of photoexcited holes from perovskite directly to the conductive substrate. The bladed hole-transport-layer-free PSCs showed a stabilized power conversion efficiency above 20.0%. This work represents a significant step towards the scalable, cost-effective manufacturing of PSCs with both high performance and simple fabrication processes. The existing hole-transporting materials cause problems in the cost and scalability of the perovskite solar cells. Here Wu et al. fabricate high efficiency cells by molecularly doping the perovskite layer without using hole-transporting layers, thus simplify the device architecture and processing steps.