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•The cycles and regeneration of Co(III)/Co(II) and Fe(III)/Fe(II) control reaction kinetics.•The sulfate radical play a crucial role in degrading TC.•The possible degradation ...mechanism of tetracycline is proposed by DFT calculations.•Toxicity of incomplete degradation intermediates is significantly weakened.
High-effective catalyst for activating peroxymonosulfate (PMS) to degrade pollutant in wastewater and minimize its toxicity is crucial. Herein, CoFe2O4/montmorillonite composites (CF/MO) were synthesized and used as high-effective PMS catalysts for the degradation of tetracycline (TC). The CoFe2O4 nanoparticles were firmly loaded on the surface of MO with FeOAl bonds, preventing the leaching of metal ions and bringing superior reusability and stability. It was optimized that the 20%-CF/MO showed superior catalytic activity to activate PMS for TC degradation, and SO4− was the dominant active species for TC complete degradation within 30 min and achieved high kinetic rate of 0.178 min−1. The ultrahigh catalytic performance toward TC degradation was ascribed to the cycles and regeneration of Co(III)/Co(II) and Fe(III)/Fe(II) synthergetic surface redox couples in the catalysts. The TC degradation pathway and reaction mechanism in the 20%-CF/MO/PMS system were also proposed based on DFT calculation. The ecotoxicity of degradation products was assessed using proteomics, and the toxicity of TC was found to decrease significantly as the reaction progressed.
Bianba is a Chinese fermented food with a long history, whereas the microorganisms involved in its fermentation remain poorly understood. Currently, a strain of Lactiplantibacillus plantarum was ...isolated from Bianba and named L3. Genomic analysis emphasized the functional annotation of protein-coding genes in L3 specifically for carbohydrate utilization. Risk sequences (antibiotic resistance and virulence genes) were detected, and L3 was deemed safe based on the outcomes of tests for antibiotic resistance, hemolysis, and gelatinase production. The L3 strain shows promise as an ideal culture for initiating yogurt fermentation due to its robust acid production and high tolerances to acid, bile salts, and gastric acids. Compared with the commercial starter fermented yogurt, the yogurt produced by L3 (L3Y) had a lower pH value, viscosity, and hardness, higher acidity, syneresis, and gumminess. Notably, the L3 cells in L3Y remained viable at levels greater than 10 log CFU/g even after being stored at 4 °C for 21 d without a significant decrease, and L3Y showed higher concentrations of important volatile flavor compounds, such as acetoin and diacetyl. Our results showed L3 carried safety characteristics and good potential to be applied in yogurt, which would be of interest to the dairy industry.
•An unrecorded L. plantarum strain L3 was isolated from Chinese traditional fermented food.•L3 was proved to be safe from the genomic and phenotypical perspectives.•L3 carries good potential to be applied in dairy products.•Viable L3 cells in yogurt changed insignificantly after stored at 4 °C for 21 d.•L3 produced relatively higher concentrations of acetoin and diacetyl in yogurt.
Safety assurance is of paramount importance in the air transportation system. In this paper, we analyze the historical passenger airline accidents that happened from 1982 to 2006 as reported in the ...National Transportation Safety Board (NTSB) aviation accident database. A four-step procedure is formulated to construct a Bayesian network to capture the causal relationships embedded in the sequences of these accidents. First of all, with respect to each accident, a graphical representation is developed to facilitate the visualization of the escalation of initiating events into aviation accidents in the system. Next, we develop a Bayesian network representation of all the accidents by aggregating the accident-wise graphical representations together, where the causal and dependent relationships among a wide variety of contributory factors and outcomes in terms of aircraft damage and personnel injury are captured. In the Bayesian network, the prior probabilities are estimated based on the accident occurrence times and the aircraft departure data from the Bureau of Transportation Statistics (BTS). To estimate the conditional probabilities in the Bayesian network, we develop a monotonically increasing function, whose parameters are calibrated using the probability information on single events in the available data. Finally, we develop a computer program to automate the generation of the Bayesian network in compliance with the XML format used in the commercial GeNIe modeler. The constructed Bayesian network is then fed into GeNIe modeler for accident analysis. The mapping of the NTSB data to a Bayesian network facilitates both forward propagation and backward inference in probabilistic analysis, thereby supporting accident investigations and risk analysis. Several accident cases are used to demonstrate the developed approach.
•A Bayesian network is developed to model event sequences in NTSB accident database.•We develop an end-to-end approach to automate the construction of Bayesian network.•Two case studies are conducted to show the performance of the Bayesian network.
•CAV data enabled adaptive signal control strategies to enhance safety environment.•Innovated mechanism and data models to evaluate CAV data potentials for safety.•SSAM integrated into the developed ...data fusion models to support safety evaluation.•The proof-of-concept study suggests positive benefits from operation and safety.
Given the connected and autonomous vehicle (CAV) generated trajectories as a “floating sensor” data source to obtain high resolution CAV-generated mobility data at intersections, to ensure maximum safety effect while maintaining efficient operations at the same time is actually a complex task in traffic management. Literature indicates that methods for evaluating the CAV-generated data potentials focusing on safety benefits are still immature. The primary reason lies in lack of underlying mechanism and data models to make the data intelligent to enhance safety environment through adaptive traffic signal control. On top of the developed intelligent CAV-generated mobility data fusion model framework in support of adaptive traffic signal control, parameters and models included in Surrogate Safety Assessment Model (SSAM) are integrated to indicate the risk of near crashes and then evaluate the safety environment. A proof-of-concept study is conducted in Uptown Cincinnati, Ohio to test the developed data fusion models in terms of safety enhancement, along with operational benefits. In the tests, the CAV-generated data supported developed adaptive signal plan is compared with the basic signal plans (i.e., pretimed signal plan, actuated signal plan) that supported by traditional detection systems. The results indicate that the adaptive signal plan has a great potential to decrease at most 91% of total collision risk (measured in probability), 71% of crossing collision risk, 90% of rear end collisions risk and 100% of lane-changing collisions risk, compared with basic signal plans. Meanwhile, it increases up to 6.8% of throughput, and decreases up to 91.49% of average delay, 96.23% of queue length and 75.00% of number of stops. The benefits of operation efficiency include reduced average delay and reduced number of stops; but no improvement in reducing collisions severity that is reflected by high maximum speed and relative speed of two vehicles involved in a potential collision.
Probiotics are live microorganisms which, when administered in adequate amounts, confer a health benefit on the host. Among the different microbial types, lactobacilli have been explored most ...extensively as potential therapeutics in human health. Lactobacilli belong to the human normal microbiota of the gastro-intestinal and urogenital tracts and have been traditionally used as starter cultures in the preparation of fermented foods. They are considered extremely safe as compared to pharmacological agents since there have been very rare reports of any adverse effects. However, the safety of probiotics is of paramount importance as new strains are continuously evolving and being commercialized. The introduction of a new probiotic strain demands that it is at least as safe as its conventional counterparts. The newly emerging strains of probiotic lactobacilli with specific health claims may not necessarily have a documented history of safe use, hence, their safety is a matter of great concern from public health perspective. Moreover, it is now well recognized that the specific health claims associated with probiotics are highly strain specific, therefore, their safety needs to be assessed very comprehensively at strain level on case to case basis. Hence, an attempt have been made in this review to focus, at the preclinical level, on the various in vitro and in vivo tests using appropriate animal models, for assessing the safety and toxicity of probiotic organisms with a special emphasis on lactobacilli.
Sensitivity analysis answers questions about the influence of parameters on the simulation results and plays a significant role in the development of environmental models by helping to understand the ...relations within the model and test its adequacy. Comparison of various sensitivity analysis approaches is often also quite useful because different methods employ different measures for ranking model parameters and their unconformities and disagreements provide additional information on model behavior.
The visual representation of numerical results is crucial for their correct interpretation, and at first sight, the visualizations for the sensitivity analysis should be quite universal because in most cases an outcome of sensitivity analysis is the same: a set of indices measuring the significance of model inputs for the selected output. Surprisingly, it is not so straightforward.
This paper compares visualization types suitable for the graphical representation of the sensitivity indices and demonstrates their benefits and caveats in different cases.
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•The paper compares visualization types suitable for the graphical representation of the sensitivity indices.•The visualization choice while dealing with more than one set of sensitivity indices depends on the message to be communicated.•While bar charts are universal during the analysis, stacked bars and heatmap are a better fit for conveying final results.
Environmental exposure to nanoplastics is inevitable as the application of nanoplastics in our daily life is more and more extensively. So, the adverse effects of nanoplastics on human health are ...also gaining greater concerns. However, the subsequent toxicological response to nanoplastics, especially on cardiovascular damage was still largely unknown. In this regard, the evaluation of cardiovascular effects of nanoplastics was performed in zebrafish embryos. The results indicated that the no observed adverse effect level (NOAEL) of nanoplastics is 50 μg/mL. The pericardial toxicity and hemodynamic changes were assessed by Albino (melanin allele) mutant zebrafish line. Severe pericardial edema was observed in zebrafish embryos after exposure to nanoplastics. At the concentration higher than NOAEL, nanoplastics significantly decreased the cardiac output (CO) and blood flow velocity. The fluorescence images manifested that the nanoplastics could inhibit the subintestinal angiogenesis of transgenic zebrafish embryos line Tg (fli-1: EGFP), which might disturb the cardiovascular formation and development. The resulting vascular endothelial dysfunction and hypercoagulable state of circulating blood further accelerated thrombosis. Reactive oxidative stress (ROS) and systemic inflammation were also found in Wild AB and Tg (mpo: GFP) zebrafish embryos, respectively. We also found many neutrophils recruiting in the tail vein where the zebrafish embryo thrombosis occurred. Our data suggested that nanoplastics could trigger the cardiovascular toxicity in zebrafish embryos, which could provide an essential clue for the safety assessment of nanoplastics.
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•Nanoplastics cause pericardial edema and cardiac toxicity in zebrafish embryos.•The endothelial damage and hemodynamics changes were caused by nanoplastics.•Oxidative stress and systemic inflammation were critical in nanoplastics-induced embryotoxicity.
During the last decade, therapeutic oligonucleotide drugs (OND) have witnessed a tremendous development in chemistry and mechanistic understanding that have translated into successful clinical ...applications. Depending on the specific OND mechanism, chemistry, and design, the DMPK and toxicity properties can vary significantly between different OND classes and delivery approaches, the latter including lipid formulations or conjugation approaches to enhance productive OND uptake. At the same time, with the only difference between compounds being the nucleobase sequence, ONDs with same mechanism of action, chemistry, and design show relatively consistent behavior, allowing certain extrapolations between compounds within an OND class. This chapter provides a summary of the most common toxicities, the improved mechanistic understanding and the safety assessment activities performed for therapeutic oligonucleotides during the drug discovery and development process. Several of the considerations described for therapeutic applications should also be of value for the scientists mainly using oligonucleotides as research tools to explore various biological processes.
Microorganisms involved in food fermentation not only improve the aroma and taste of the food, but also enhance its preservation. Thus, they are added as starter cultures to boost the final product ...quality of commercial fermented foods. Although these microorganisms originate from fermented foods and have a long history of consumption, the European Union recently applied the concept of Qualified presumption of Safety (QPS), which is a safety evaluation system for microorganisms used in food or feed in Europe. The QPS system is a species-level safety system and shares results with the European Novel Food System, a strain-level safety evaluation system. In the United States, microorganisms added to fermented foods are considered as food additives or Generally Recognized as Safe substance. In Korea, food microbe lists are presented at the species level. Moreover, the nation has established a strain-oriented evaluation system that applies temporary safety evaluation methods for food raw materials as well as new raw materials. However, when it comes to microorganisms isolated from traditional fermented foods and other fermented food products, there is no definition of the term “species,” and there is a lack of an evaluation system at the species level. Therefore, such an evaluation system for microbial species used in Korean fermented foods is necessary.
Determining adversity of effects in toxicology studies continues to pose a dilemma to practicing toxicologists and pathologists. How this determination is made may follow either a focused or broad ...approach to assessing the study data. The choice of which approach is best is dependent on a variety of factors. Therefore, we present a philosophical perspective on the determination of adversity across toxicology studies that may be applied in inhalation studies and those conducted by other routes of exposure.
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