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991.
Beladenta Amalia Marcela Fu Olena Tigova Montse Ballbè Yolanda Castellano Sean Semple Luke Clancy Constantine Vardavas Maria J. López Nuria Cortés Raúl Pérez-Ortuño José A. Pascual Esteve Fernández 《Indoor air》2021,31(5):1601-1613
Secondhand electronic cigarette (e-cigarette) aerosol (SHA) might impair indoor air quality and expose bystanders. This study aims to investigate exposure to SHA in controlled conditions of enclosed settings simulating real-world scenario. An experiment was performed in a car and in a room, in which SHA was generated during a 30-minute ad libitum use of an e-cigarette. The experiment was replicated on five consecutive days in each setting. We measured PM2.5, airborne nicotine concentrations, and biomarkers of exposure to SHA, such as nicotine metabolites, tobacco-specific nitrosamines, propylene glycol, and glycerol in bystanders’ saliva samples before, during, and after the exposure period. Self-reported health symptoms related to exposure to SHA were also recorded. The results showed that the highest median PM2.5 concentration was recorded during the exposure period, being 21 µg/m3 in the room setting and 16 µg/m3 in the car setting—about twofold increase compared to the baseline. Most concentrations of the airborne nicotine and all biomarkers were below the limit of quantification in both settings. Bystanders in both settings experienced some short-term irritation symptoms, expressed as dry throat, nose, eyes, and phlegm. In conclusion, short-term use of an e-cigarette in confined spaces increased indoor PM2.5 level and caused some irritation symptoms in bystanders. 相似文献
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993.
SA-SP-PEI were synthesized via acylation reaction between carboxyl-modified soybean protein (SA-SP) and branched polyethylenimine (PEI) with molecular weight of 600, 1200, and 1800?Da, and designed as SA-SP-PEI600, SA-SP-PEI1200, and SA-SP-PEI1800, respectively. SA-SP-PEI could effectively condense plasmid DNA into nanoscale polyplexes and protect them from enzymatic digestion. MTT assay revealed that SA-SP-PEI exhibited reduced cytotoxicity on 293?T and SH-SY5Y cells. SA-SP-PEI1800/DNA complexes hold highest transfection efficiency on 293?T and SH-SY5Y cells with or without 10% serum, which was owing to its better serum stable and improved biocompatibility. Such polycationic soybean proteins have great potentials as gene carriers by further optimization. 相似文献
994.
A Multilevel Recognition Model of Water Inrush Sources: A Case Study of the Zhaogezhuang Mining Area
Lin Gang Jiang Dong Dong Donglin Fu Jingying Li Xiang 《Mine Water and the Environment》2021,40(3):773-782
Mine Water and the Environment - Discriminating water inrush sources efficiently and accurately is necessary to control water in coal mines. We combined the improved genetic algorithm (IGA) and... 相似文献
995.
The networks-on-chip (NoC) communication has an increasingly larger impact on the system power consumption and performance. Emerging technologies, like surface wave, are believed to have lower transmission latency and power consumption over the conventional wireless NoC. Therefore, this paper studies how to optimize the network performance and power consumption by giving the packet-switching fabric and traffic pattern of each application. Compared with the conventional method of wire-linked, which adds wireless transceivers by using the genetic algorithm (GA), the proposed maximal declining sorting algorithm (MDSA) can effectively reduce time consumption by as much as 20.4% to 35.6%. We also evaluate the power consumption and configuration time to prove the effective of the proposed algorithm. 相似文献
996.
997.
998.
Liu Xiang Tong Dongbing Chen Qiaoyu Zhou Wuneng Liao Kaili 《Neural Processing Letters》2021,53(5):3757-3781
Neural Processing Letters - Input saturation is one of the common phenomena in many practical systems, and it is main obstacles that limits the systems performance. In this paper, the adaptive... 相似文献
999.
Ziyang Jia Heng Yang Yudong Zhang Wenping Ding Yuan Shuang Yang Fu Qianran Xie Tongjun Dong Yan Wu Xuedong Wang 《International Journal of Food Science & Technology》2022,57(4):2310-2320
The effects of different isomalt concentrations on the quality of wheat flour dough and spicy wheat gluten sticks (SWGS) were evaluated at the physical, structural and molecular levels. The results showed that the radial expansion rate (RER) and oil absorption rate (OAR) of SWGS increased first and then decreased with increased isomalt supplementation, which reached the maximum at 3 wt%. The pasting properties of wheat starch also changed, and the peak viscosity, breakdown and setback were decreased with the addition of isomalt. Dynamic rheological properties results showed that the storage modulus (G') and loss modulus (G'') increased with the addition of isomalt, which may be attributed to the reinforcement of gluten network structure by hydrogen bonding of isomalt. Scanning electron microscopy (SEM) images illustrated that the SWGS surface becomes smooth and the broken gluten structure was reduced after the addition of different isomalt levels compared with the control group. Overall, the wheat flour dough quality analysis showed that the addition of isomalt could generate a close binding with wheat starch and protein and further strengthen the internal structure of gluten through isomalt hydrogen bonds. 相似文献
1000.
In this paper, we demonstrated the processing of Li7La3Zr0.5Nb0.5Ta0.5Hf0.5O12 (LLZNTH) high-entropy Li–garnet with promising properties for lithium batteries. We first synthesized the LLZNTH Li–garnet powders which have a single cubic garnet phase (space group: ; No. 230) without any secondary phases as well as uniform elements distributions. The prepared powders were further densified to a relative density of ∼94% with well-crystallized grains and good contact with the neighboring grains. Minimal grain growth can be observed in the sintering time range from 8 to 20 h, which is likely due to the sluggish effects of high-entropy compounds. The sample also maintains the cubic garnet phase along with uniform elements distribution after sintering. Electrochemical characterizations indicate that the densified sample has an adequate ionic conductivity of 4.67 × 10−4 S cm−1 at room temperature, a low activation energy of 0.25 eV, and a low electronic conductivity in the order of 10−8 S cm−1. The significance of designing high-entropy electrolyte is further discussed. 相似文献