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Objective: Since December 2019, a new coronavirus viral was initially detected in Wuhan, China. Population migration increases the risk of epidemic transmission. Here, the objective of study is to estimate the output risk quantitatively and evaluate the effectiveness of travel restrictions of Wuhan city. Methods: We proposed a modified susceptible-exposed-infectious-recovered (SEIR) dynamics model to predict the number of coronavirus disease 2019 (COVID-19) symptomatic and asymptomatic infections in Wuhan. And, subsequently, we estimated the export risk of COVID-19 epidemic from Wuhan to other provinces in China. Finally, we estimated the effectiveness of travel restrictions of Wuhan city quantitatively by the export risk on the assumption that the measure was postponed. Results: The export risks of COVID-19 varied from Wuhan to other provinces of China. The peak of export risk was January 21-23, 2020. With the travel restrictions of Wuhan delayed by 3, 5, and 7 d, the export risk indexes will increase by 38.50%, 55.89%, and 65.63%, respectively. Conclusions: The results indicate that the travel restrictions of Wuhan reduced the export risk and delayed the overall epidemic progression of the COVID-19 epidemic in China. The travel restrictions of Wuhan city may provide a reference for the control of the COVID-19 epidemic all over the world. [ABSTRACT FROM AUTHOR]

Plasticizer migration is responsible for premature coating failure in polyvinyl chloride (PVC) synthetic materials that continue to benefit our daily life as a reliable and cost-efficient simulant of genuine leather. In this context, the establishment of standard assays that measure the migration rate of plasticizers under varying scenarios plays a pivotal role in comparing durability of those PVC-derived leather-simulants. In this review, multiple methodologies developed over the last decade for determining plasticizer migration from PVC coating are compiled, with their operational principles, merits, and limitations being taken into consideration along with specific apparatus required for each. A concluding section discusses current challenges in this field, and highlights how nuclear magnetic resonance and computational simulation surpass conventional assays in yielding intercomparable results, and hence screening migration-resistant plasticizers in a labor- and time-saving way. Since migration resistance represents a decisive performance indicator of plasticizers, this systematic review may provide guidance to quite a few practitioners in PVC synthetic material industry, who are now engaged in validating various sustainable alternatives with performance allegedly equal to conventional but toxic di-(2-ethylhexyl) phthalate plasticizer. [ABSTRACT FROM AUTHOR]

A core shell structure, large particle self-extinction acrylic resin emulsion is prepared by semi continuous feeding method through seed emulsion polymerization-three successive nucleation growth and shell polymerization. The effects of different feeding methods on the particle size of seed latex particles and the method of continuous growth of core latex particles are investigated. Simultaneously, the influence of latex particle size, core-shell structure and crosslinking degree on the extinction of acrylic resin coating is also sided. The results show that the seed latex particles with large particle size can be obtained by semi-continuous feeding method. By controlling the concentration of emulsifier and monomer, the nucleation mechanism is oligomer nucleation, and the growth of latex particles is dominant in the reaction, so as to outgain the seed latex particles with large Particle size (about 200 nm). After three times growth, the particle size of seed latex particles can reach about 700 nm. Finally after shell-shell polymerization, the particle size of coreshell latex is increased to about 800 nm. Latex particle size has an important influence on the gloss of the coating. Large latex particle size will produce rough microstructure on the coating surface and reduce the gloss of the coating, while the soft core-hard shell structure makes it difficult for latex particles to deform and integrate during film formation, leading to improve the roughness and extinction of the coating. At the same time, the shell density is also an important factor affecting the gloss of coating. After the introduction of crosslinking agent, the density of shell structure increases and the degree of freedom of polymer chains decreases, which retards the latex particles deform and fuse. As a result, the roughness of the coating surface is further increased, and the gloss of the PVC leather coating can be adjusted to 1.2°. [ABSTRACT FROM AUTHOR]

Background: Crush injury/crush syndrome (CI/CS) is the second most common cause of death during earthquakes. Most studies of CI/CS have mainly focused on kidney injury after decompression. Few studies have focused on myocardial injury caused by crush injury and its potential mechanisms. Methods: We first verified cardiomyocyte injury during compression in rats with a crush injury. The survival rate, electrocardiographic results, histological results, catecholamine changes and cardiac β1-AR expression were evaluated. Next, we explored the effects of pretreatment with a selective β1-blocker (bisoprolol) with or without fluid resuscitation on rats with a crush injury. In addition to evaluating the survival rates, biochemical and histological analyses and echocardiographic measurements were also performed. Results: Reduced heart rates, elevated ST segments, and tall-peaked T waves were observed in the rats with a crush injury. The changes in the myocardial enzymes and pathological results demonstrated that myocardial damage occurred during compression in rats with a crush injury. The levels of the catecholamine norepinephrine in both the serum and myocardial tissue were elevated during compression. Pretreatment with a selective β1-blocker combined with fluid resuscitation significantly improved the survival rates of the rats with lethal crush injury. The myocardial enzymes and pathological results showed that the combined therapy decreased myocardial damage. The echocardiography measurements showed that the rats that received the combined therapy exhibited decreased left ventricular mass (LVM), left ventricular volume at end-systole (LVVs) and left ventricular internal diameter (LVID) compared with the rats with a crush injury. Conclusions: Our findings demonstrated the presence of myocardial injury in the early stage of compression in rats with a crush injury. Pretreatment with a β1-blocker (bisoprolol) with fluid resuscitation significantly reduced mortality, decreased myocardial tissue damage, and improved ventricular remodelling in rats with a lethal crush injury. [ABSTRACT FROM AUTHOR]

In this article, the development course and current research status of physiological information monitoring equipment are briefly reviewed and analyzed. The research progress of cardiopulmonary resuscitation (CPR) equipment at home and abroad, as well as the advantages and disadvantages of existing CPR equipment, are the main points of discussion. This article discusses the design feasibility and technical points of the portable integrated basic life support machine, based on existing equipment and technology, and summarizes possible interesting future research directions. [ABSTRACT FROM AUTHOR]

Background: Investigations on the potential effects of ambient fine particulate matter (PM2.5) on large for gestational age (LGA) are limited. Furthermore, no study has explored weekly-specific susceptible exposure windows for small for gestational age (SGA) and LGA. This study evaluated the associations of exposure to ambient PM2.5 over the preconception and entire-pregnancy periods with risks of SGA and LGA, as well as explored critical weekly-specific exposure windows.Methods: 10 916 singleton pregnant women with 24-42 completed gestational weeks from the Project Environmental and LifEstyle FActors iN metabolic health throughout life-course Trajectories between 2014 and 2016 were included in this study. Distributed lag models (DLMs) incorporated in Cox proportional-hazards models were applied to explore the associations of maternal exposure to weekly ambient PM2.5 throughout 12 weeks before pregnancy and pregnancy periods with risks of SGA and LGA after controlling for potential confounders.Results: For a 10-μg/m3 increase in maternal exposure to PM2.5, positive associations with SGA were observed during the 1st to 9th preconceptional weeks and the 1st to 2nd gestational weeks (P<0.05), with the strongest association in the 5th preconceptional week [hazard ratio (HR), 1.06; 95% confidential interval (CI), 1.03-1.09]. For LGA, positive associations were observed during the 1st to 12th preconceptional weeks and the 1st to 5th gestational weeks (P<0.05), with the strongest association in the 7th preconceptional week (HR, 1.10; 95% CI, 1.08-1.12).Conclusions: Exposure to high-level ambient PM2.5 is associated with increased risks of both SGA and LGA, and the most susceptible exposure windows are the preconception and early-pregnancy periods. [ABSTRACT FROM AUTHOR]

Counterfeit leather products infringe the intellectual property rights of the business, cause enormous economic loss, and negatively influence the business enthusiasm for innovation. However, traditional anti-counterfeiting materials for leather products suffer from complicated fabrication procedures, photobleaching, and high volatile organic compound (VOC) emissions. Here, a sustainable and invisible anti-counterfeiting ink composed of waterborne polyurethane and water-dispersible lanthanide-doped upconversion nanoparticles (UCNPs) featuring ease of preparation, high photostability, non-toxicity, low VOC emissions, and strong adhesion strength for leather products is designed and synthesized. After decorating on the surface of leather products, the obtained patterns are invisible under normal light conditions. Upon irradiation at 808 nm, the invisible patterns can be observed by naked eyes due to the visible light emitted by 808 nm excited UCNPs. Our approach described here opens a new pathway to realize the long-term, stable anti-counterfeiting function of leather products. [ABSTRACT FROM AUTHOR]

Since December 2019, several new infectious diseases, mainly lung diseases caused by novel coronavirus infections, have been discovered in Wuhan, Hubei Province. With the spread of the epidemic, cases in other regions of China and abroad have been confirmed. This sudden outbreak of a new type of infectious disease has seriously threatened people's health and safety, and China has adopted strong prevention and control measures in response. To provide a reference for international health emergency management workers, this article summarizes, from an academic perspective, the main prevention and control measures taken in China. [ABSTRACT FROM AUTHOR]