ABSTRACT
The main bottlenecks limiting the practical application of primary explosives are the contradiction between safety and detonation performance, as well as the inherent brittleness of powder charge. Traditional methods to improve sensitivity performance such as adding carbon nanomaterials or embedding metal-organic framework (MOF) structure methods are mostly powders, which are inherently brittle and unsafe. Here, we report three types of typical azide aerogels that can be directly prepared and obtained in this paper by combining electrospinning with aerogel. Their electrostatic sensitivity and flame sensitivity were significantly improved and could be detonated successfully at an initiation voltage of 25 V, demonstrating good ignition performance. This enhancement is primarily due to the porous carbon skeleton structure evolved from a three-dimensional nanofiber aerogel, which has good thermal and electrical conductivity characteristics and can also uniformly load azide particles, contributing to improved explosive system sensitivity. The most important aspect of this method is that it can directly prepare molded explosives, which can be matched with the micro-electrical-mechanical system (MEMS) process, and it offers a new idea for the preparation of high-security molded explosives.
ABSTRACT
Background: Acute myocardial infarction (AMI) with pulmonary edema shows a worse prognosis. Lung ultrasound (LUS) is a new tool for evaluating subclinical pulmonary congestion. It has been proved to predict prognosis in heart failure; however, whether it can be used as a short-term prognostic marker in AMI and provide incremental value to Killip classification is unknown. Methods: We performed echocardiography and LUS by the 8-zone method in patients enrolled in Guangdong Provincial People's Hospital undergoing percutaneous coronary intervention for AMI from March to July 2021. The lung water detected by LUS was defined as B-lines, and the sum of the B-line number from 8 chest zones was calculated. Besides, the classification into LUS according to the pulmonary edema severity was as follows: normal (B-line numbers <5), mild (B-line numbers ≥5 and <15), moderate (B-line numbers ≥15 and <30), and severe (B-line numbers ≥30). The NT-proBNP analysis was performed on the same day. All patients were followed up for 30 days after discharge. The adverse events were defined as all-cause death, worsening heart failure in hospitalization, or re-hospitalization for heart failure during the follow-up. Results: Sixty three patients were enrolled consecutively and followed up for 30 days. The number of B-lines at admission (median 7[3-15]) was correlated with NT-proBNP (r = 0.37, p = 0.003) and negatively correlated with ejection fraction (r = -0.43; p < 0.001) separately. In the multivariate analysis, B-line number was an independent predictor of short-term outcomes in AMI patients (in-hospital, adjusted OR 1.13 [95% CI: 1.04-1.23], P = 0.006; 30-day follow-up, adjusted OR 1.09 [95% CI: 1.01-1.18], P = 0.020). For in-hospital results, the area under the receiver operating characteristic curves (AUCs) were 0.639 (P = 0.093), 0.837 (P < 0.001), and 0.847 (P < 0.001) for Killip, LUS and their combination, respectively. For the diagnosis of 30-day adverse events, the AUCs were 0.665 for the Killip classification (P = 0.061), 0.728 for LUS (P = 0.010), and 0.778 for their combination (P = 0.002). Conclusion: B-lines by lung ultrasound can be an independent predictor of worsening heart failure in AMI during hospitalization and short-term follow-up and provides significant incremental prognostic value to Killip classification.
ABSTRACT
Environmental pollution due to primitive e-waste dismantling activities has been intensively investigated over the last decade in the south-eastern coastal region of China. In the present study, we investigated the distribution and composition of polycyclic aromatic hydrocarbons (PAHs) in soils and plants around e-waste recycling sites in Longtang, Guangdong province, South China. The results indicated that PAH concentrations in rhizosphere soil and non-rhizosphere soil were in the range of 133 to 626 ng/g and 60 to 816 ng/g, respectively, while PAH levels in plant tissue were 96 to 388 ng/g in shoots and 143 to 605 ng/g in roots. PAHs were enriched in rhizosphere soils in comparison with non-rhizosphere soils. The concentrations of PAHs in plant tissues varied greatly among plant cultivars, indicating that the uptake of PAHs by plants is species-dependent. Different profiles of PAHs in the soil and the corresponding plant tissue implied that PAH uptake and translocation by plants were selective.The total daily intakes of PAHs and carcinogenic PAHs through vegetables at the e-waste recycling site were estimated to be 99 and 22 ng/kg/day, respectively, suggesting that potential health risks associated with the consumption of contaminated vegetables should not be ignored.
