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With advances in vehicle emission control technology, updating source profiles to meet the current requirements of source apportionment has become increasingly crucial. In this study, on-road and non-road vehicle particles were collected, and then the chemical compositions of individual particles were analyzed using single particle aerosol mass spectrometry. The data were grouped using an adaptive resonance theory neural network to identify signatures and establish a mass spectral database of mobile sources. In addition, a deep learning-based model (DeepAerosolClassifier) for classifying aerosol particles was established. The objective of this model was to accomplish source apportionment. During the training process, the model achieved an accuracy of 98.49 % for the validation set and an accuracy of 93.36 % for the testing set. Regarding the model interpretation, ideal spectra were generated using the model, verifying its accurate recognition of the characteristic patterns in the mass spectra. In a practical application, the model performed hourly source apportionment at three specific field monitoring sites. The effectiveness of the model in field measurement was validated by combining traffic flow and spatial information with the model results. Compared with other machine learning methods, our model achieved highly automated source apportionment while eliminating the need for feature selection, and it enables end-to-end operation. Thus, in the future, it can be applied in refined and online source apportionment of particulate matter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The bioactivity of tea polysaccharides (TPs) has been widely reported, but studies to date have focused on green tea. Some human health investigations have implied that black tea may possess potential antidiabetic effects, but less is known about their potential role and related antidiabetic mechanism. The present study was, therefore, conducted to investigate the chemical properties and antidiabetic activity of TPs from black tea. Monosaccharide composition revealed that Alduronic acid (77.8 mol%) considerably predominated in the fraction. TP conformation analysis indicated that three components in TPs were all typical of high-branching structures. Oral administration of TPs could effectively alleviate fasting blood glucose in type 2 diabetes mellitus (T2D) mice, with the values 23.6 ± 1.42, 19.6 ± 2.25, and 16.4 ± 2.07 mmol/L in the 200, 400, and 800 mg/kg·BW groups, respectively. Among these TPs groups, the 800 mg/kg·BW groups significantly decreased by 37.88% when compared with the T2D+water group ( p < 0.05). Further studies demonstrated that TP treatment upregulated the expression of p-Akt/p-PI3K ( p < 0.001). Additionally, TP treatment significantly promoted glucose transporter protein 2 (GLUT2) translocation in the liver ( p < 0.001). These findings suggest that TPs from black tea protect against T2D by activating PI3K/Akt/GLUT2 signaling and might serve as a novel therapeutic candidate for T2D., Competing Interests: The authors declare that they have no conflicts of interest concerning this article.

Organic nitrogen (ON) compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols, however, the mixing state, secondary formation processes, and influencing factors of ON compounds are still unclear. This paper reports on the mixing state of ON-containing particles based on measurements obtained using a high-performance single particle aerosol mass spectrometer in January 2020 in Guangzhou. The ON-containing particles accounted for 21% of the total detected single particles, and the particle count and number fraction of the ON-containing particles were two times higher at night than during the day. The prominent increase in the content of ON-containing particles with the enhancement of NO x mainly occurred at night, and accompanied by high relative humidity and nitrate, which were associated with heterogeneous reactions between organics and gaseous NO x and/or NO 3 radical. The synchronous decreases in ON-containing particles and the mass absorption coefficient of water-soluble extracts at 365 nm in the afternoon may be associated with photo-bleaching of the ON species in the particles. In addition, the positive matrix factorization analysis found five factors dominated the formation processes of ON particles, and the nitrate factor (33%) mainly contributed to the production of ON particles at night. The results of this study provide unique insights into the mixing states and secondary formation processes of the ON-containing particles., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Many Dendrobium species, which hold a high status and value in traditional Chinese medicine, grow on barks and rocks in the wild, often encountering harsh environments and facing droughts. However, the molecular mechanisms underlying the shift in the photosynthetic pathway induced by drought remain unclear. To address this issue, three Dendrobium species with different photosynthetic pathways were selected for sequencing and transcriptome data analysis after drought treatment. The findings included 134.43 GB of sequencing data, with numerous Differentially Expressed Genes (DEGs) exhibiting different response mechanisms under drought stress. Gene Ontology (GO)-KEGG-based enrichment analysis of DEGs revealed that metabolic pathways contributed to drought tolerance and alterations in photosynthetic pathways. Phosphoenolpyruvate Carboxylase (PEPC) was subjected to phylogenetic tree construction, sequence alignment, and domain analysis. Under drought stress, variations were observed in the PEPC gene structure and expression among different Dendrobium species; the upregulation of Dc&#95;gene2609 expression may be caused by dof-miR-384, which resulted in the shift from C 3 photosynthesis to CAM, thereby improving drought tolerance in Dendrobium . This study revealed the expression patterns and roles of PEPC genes in enhancing plant drought tolerance and will provide an important basis for in-depth research on Dendrobium 's adaptation mechanisms in arid environments.

The structure and bioactivity of a novel polysaccharide from Dendrobium Chrysotoxum Lindl (DCP-1) were investigated. The crude polysaccharides of Dendrobium Chrysotoxum Lindl (DCP) were extracted by hot water extraction, and the protein was removed by enzymatic hydrolysis and Sevage. After purification, the chemical structure of polysaccharides was identified by infrared spectroscopy, methylation analysis and nuclear magnetic resonance spectroscopy. Then, a mouse model of acute kidney injury (AKI) was constructed using lipopolysaccharide (LPS), and pretreated with DCP. Structure characterization demonstrated that the number-average molecular weight and mass average molar mass of DCP-1 were 28.43 kDa and 15.00 kDa, respectively. DCP-1 mainly consisted of mannose (37.8 %) and glucose (55.6 %). The main linkage types of DCP-1 were contained 1,4-Linked Manp and 1,4-Linked Glcp. And DCP-1 was demonstrated to be an O-acetylglucomannan with β-ᴅ-configuration in pyranoid form. Besides, the bioactivity of DCP was further investigated. The results showed that DCP exhibited notable anti-inflammatory activity in LPS-induced AKI mice. After treated with DCP, the creatinine (CREA) and urea nitrogen (BUN) in serum were successfully down-regulated in AKI mice. DCP treatment prevented the characteristic morphological changes of LPS-induced renal tubular injury. The results showed that DCP treatment significantly reduced the concentration of oxidative damage indicators (MDA, SOD) and the expression of inflammatory indices (TNF-α, IL-6, MCP-1, COX-2). In general, the newly extracted polysaccharide DCP showed excellent nephroprotective effect, which enabled it to be an ideal natural medicine for kidney diseases therapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

To summarize the nursing experience of treating pediatric fulminant myocarditis with extracorporeal membrane oxygenation (ECMO). The intensive care unit of our hospital treated 6 children with fulminant myocarditis with ECMO from 2019 to 2022. The main nursing measures included establishing an ECMO rescue team, preparing before initiation of ECMO, management of arterial and venous catheters, enteral nutrition support, reducing the risk of infection aggravation, anticoagulation management, prevention of bleeding and thrombosis, management of ECMO pump failure, and post-ECMO care. One child's family abandoned treatment and left the hospital, while the other 5 children were transferred to the cardiovascular department after stable weaning from ECMO and continued treatment, with good condition, and eventually discharged. Pediatric fulminant myocarditis has a high mortality rate, but detailed evaluation and nursing care can improve the outcome of these patients., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Dendrobium officinale is edible and has medicinal and ornamental functions. Polysaccharides and flavonoids, including anthocyanins, are important components of D. officinale that largely determine the nutritional quality and consumer appeal. There is a need to study the molecular mechanisms regulating anthocyanin and polysaccharide biosynthesis to enhance D. officinale quality and its market value. Here, we report that high light (HL) induced the accumulation of polysaccharides, particularly mannose, as well as anthocyanin accumulation, resulting in red stems. Metabolome and transcriptome analyses revealed that most of the flavonoids showed large changes in abundance, and flavonoid and polysaccharide biosynthesis was significantly activated under HL treatment. Interestingly, DoHY5 expression was also highly induced. Biochemical analyses demonstrated that DoHY5 directly binds to the promoters of DoF3H1 (involved in anthocyanin biosynthesis), DoGMPP2, and DoPMT28 (involved in polysaccharide biosynthesis) to activate their expression, thereby promoting anthocyanin and polysaccharide accumulation in D. officinale stems. DoHY5 silencing decreased flavonoid- and polysaccharide-related gene expression and reduced anthocyanin and polysaccharide accumulation, whereas DoHY5 overexpression had the opposite effects. Notably, naturally occurring red-stemmed D. officinale plants similarly have high levels of anthocyanin and polysaccharide accumulation and biosynthesis gene expression. Our results reveal a previously undiscovered role of DoHY5 in co-regulating anthocyanin and polysaccharide biosynthesis under HL conditions, improving our understanding of the mechanisms regulating stem color and determining nutritional quality in D. officinale. Collectively, our results propose a robust and simple strategy for significantly increasing anthocyanin and polysaccharide levels and subsequently improving the nutritional quality of D. officinale., (© 2023 Society for Experimental Biology and John Wiley & Sons Ltd.)

With potential anti-tumor and antioxidant properties, the polysaccharide content of D. nobile is relatively lower than that of the other medicinal Dendrobium. To find high-content polysaccharide resources, the polysaccharide (DHPP-Ⅰs) was prepared from D. Second Love 'Tokimeki' (a D. nobile hybrid) and compared with DNPP-Ⅰs from D. nobile . DHPP-Is (Mn 31.09 kDa) and DNPP-Is (Mn 46.65 kDa) were found to be O -acetylated glucomannans (-Glc p -(1,4) and O -acetylated-D-Man p -(1,4) backbones), analogous to other Dendrobium polysaccharides. DHPP-Ⅰs had higher glucose content (31.1%) and a lower degree (0.16) of acetylation than DNPP-Ⅰs (15.8%, 0.28). Meanwhile, DHPP-Ⅰs and DNPP-Ⅰs had the same ability in the radical scavenging assay, which was milder than the control of Vc. Both DHPP-Is and DNPP-Is inhibited SPC-A-1 cell proliferation in vitro, with obvious differences in dose concentrations (0.5-2.0 mg/mL) and treatment times (24-72 h). Therefore, the antioxidant activity of DHPP-Ⅰs and DNPP-Ⅰs is not associated with distinction in anti-proliferative activity. As a glucomannan derived from non-medicinal Dendrobium , DHPP-Ⅰs has similar bioactivity to other medicinal Dendrobium, and this could serve as a starting point for studying the conformational-bioactivity relationship of Dendrobium polysaccharides.

The distribution of vanadium (V) in aerosols is commonly used to track ship exhaust emissions, yet the atmospheric abundance of V has been greatly reduced due to the implementation of a clean fuel policy. Recent research mainly discussed the chemical compositions of ship-related particles during specific events, yet few studies focus on the long-term changes of V in the atmosphere. In this study, a single-particle aerosol mass spectrometer was used to measure V-containing particles from 2020 to 2021 in Huangpu Port in Guangzhou, China. The long-term trend of the particle counts of V-containing particles declined annually, but the relative abundance of V-containing particles in the total single particles increased in summer due to the influence of ship emissions. Positive matrix factorization revealed that in June and July 2020, 35.7% of the V-containing particles were from ship emissions, followed by dust and industrial emissions. Furthermore, more than 80% of the V-containing particles were found mixing with sulfate and 60% of the V-containing particles were found mixing with nitrate, suggesting that the majority of the V-containing particles were secondary particles processed during the transport of ship emissions to urban areas. Compared with the small changes in the relative abundance of sulfate in the V-containing particles, the relative abundance of nitrate exhibited clear seasonal variations, with a high abundance in winter. This may have been due to the increased production of nitrate from high concentrations of precursors and a suitable chemical environment. For the first time, the long-term trends of V-containing particles in two years are investigated to demonstrate changes in their mixing states and sources after the clean fuel policy, and to suggest the cautious application of V as an indicator of ship emissions.

The outbreak of novel coronavirus pneumonia in Wuhan, Hubei Province, in 2019 and its rapid spread across the country caused severe public panic in China. The purpose of this study was to investigate the mental health problems of children's chaperones at the emergency clinic during the coronavirus disease 2019 (COVID-19) outbreak and to analyze the related influencing factors. A total of 260 chaperones for children in the emergency department participated in this cross-sectional study through the questionnaire constellation platform. The survey period was from February to June 2021. Information collected included demographic data and mental health scales. The Self-Assessment Scale for Anxiety, the Self-Rating Scale for Depression, and the Pittsburgh Sleep Quality Index assessed anxiety, depression, and sleep quality, respectively. Logistic regression was used to analyze influential factors associated with mental health problems. The prevalence of depression, anxiety, and sleep disorders among family members accompanying children attending the emergency room was 41.54%, 20.00%, and 93.08%, respectively, with 21.54% of family members suffering from moderate sleep disorders. Univariate analysis showed that being in Wuhan or not during the city closure (X2 = 8.61, P < .01) was strongly associated with the occurrence of depression; female (X2 = 4.87, P = .03), working or not (X2 = 6.39, P = .01) and fear of going to the hospital (X2 = 7.80, P = .01) were key factors for the occurrence of anxiety symptoms; Knowledge of transmission routes and prevention of COVID-19 (X2 = 12.56, P = .03) was a key factor for sleep disorders; logistic stepwise regression analysis showed that fear of going to the hospital was a risk factor for anxiety symptoms (odds ratio = 2.51, P < .01, 95% confidence interval = 1.30-4.85). Our findings suggest that mental health problems were prevalent among family members accompanying children attending the emergency department during the COVID-19 outbreak, with a high prevalence of sleep disturbances in particular. Relevant factors included presence or absence in Wuhan during the outbreak closure, gender, work or absence, and fear of hospital visits. There is a need to focus on the mental health distress of the chaperones for children in the emergency department, and to provide timely intervention and diversion., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

CD1E, one of the most important glycolipid antigens on T cell membranes, is required for glycolipid antigen presentation on the cell surface. Cell-based recombinant expression systems have many limitations for synthesizing transmembrane proteins such as CD1E, including low protein yields and miss folding. To overcome these challenges, here we successfully synthesized high-quality soluble CD1E using an E.coli cell-free protein synthesis system (CFPS) with the aid of detergent. Following purification by Ni 2+ affinity chromatography, we were able to obtain CD1E with ≥90% purity. Furthermore, we used the string website to predict the protein interaction network of CD1E and identified a potential binding partner━B2M. Similarly, we synthesized soluble B2M in the E.coli CFPS. Finally, we verified the interaction between CD1E and B2M by using Surface Plasmon Resonance (SPR). Taken together, the methods described here provide an alternative way to obtain active transmembrane protein and may facilitate future structural and functional studies on CD1E., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Ground-level ozone (O 3 ) pollution has received widespread attention because its rising trend and adverse ecological impacts. However, the extremely strong photochemical reactions of its precursor volatile organic compounds (VOCs) increase the difficulty of reducing VOCs emissions to alleviate O 3 . Here, we carried out a one-year comprehensive observation in two representative cities, Tianjin (TJ, Northern China) and Guangzhou (GZ, Southern China). By revealing the concentration characteristics of three different types of VOCs, i.e., initial VOCs without photochemical reaction (In-VOCs), consumed VOCs (C-VOCs), and measured VOCs after the reaction (M-VOCs), we elucidated the important role of C-VOCs in the formation of O 3 . Although the overall trends were similar in both cities, the average concentration level of VOCs in GZ was 8.2 ppbv higher than that in TJ, and the photochemical loss of VOCs was greater by 2.2 ppbv. In addition, various drivers affecting O 3 generation from C-VOCs were specifically explored, and it was found that most alkenes of TJ were key substances for rapid O 3 formation compared to aromatics of GZ. Meanwhile, favorable meteorological conditions such as high temperature (T > 31 °C in TJ, and T > 33 °C in GZ), low relative humidity (56% in TJ and 45% in GZ), and stable atmospheric environment (proper pressure and gentle wind speed) also contribute to the generation of O 3 . More importantly, we combined chemical kinetics and receptor model to quantify the three-type VOCs source contributions and assess the potential impact of C-VOCs sources on O 3 production, thus proposing environmental abatement technologies corresponding to the three types of VOCs. The differences in the comparison results of the three-type VOCs highlight the need to reduce O 3 pollution from C-VOCs sources, which provides insights for future clean air policies development., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: To assess the association of c.109G>A (p.V37I) variant of the GJB2 gene and its types with the risk of deafness., Methods: PubMed, Embase, Cochrane Library, CNKI, Wanfang, and VIP database were searched for cases with GJB2 gene c.109G>A (p.V37I) variant and its compounds with variants of other sites from case-control studies, cohort studies and cross-sectional studies. The search time was from the establishment of database to April 2021. Two researchers have independently screened the literature according to the inclusion and exclusion criteria, extracted the data, and evaluated the included studies according to the criteria. Stata 12.0 software was used for the meta-analysis and publication bias analysis, and a sensitivity analysis was also carried out when necessary., Results: A total of 22 articles (17 in English and 5 in Chinese) were included. There were 7455 cases in the deafness group and 10 464 cases in the control group. The results of meta-analysis showed the c.109G>A (p.V37I) variant to be strongly associated with the risk of deafness (OR: 3.56, 95%CI: 2.31-5.47, P < 0.001). Analysis based on the mutational type also suggested c.109G>A (p.V37I) homozygosity (OR: 11.36, 95%CI: 5.93-21.74, P < 0.001) and compound loss of heterozygosity mutations (OR: 9.27, 95%CI: 3.97-21.64, P < 0.001) to be strongly associated with the risk of deafness. By contrast, heterozygous c.109G>A (p.V37I) variant (OR: 1.20, 95%CI: 0.72-2.00, P = 0.478) and compound heterozygous missense mutation (OR: 1.54, 95%CI: 0.98-2.44, P = 0.063) are not strongly associated with the risk., Conclusion: The homozygous c.109G>A (p.V37I) variants of the GJB2 gene and its compound deletional mutation with another GJB2 allele can significantly increase the risk of deafness. Heterozygous c.109G>A (p.V37I) variant of the GJB2 gene or its compound with a missense mutation of another GJB2 allele do not increase the risk.

The formation processes of particulate amines are closely related to their emission sources and secondary reactions, which can be revealed through the investigation of their real-time mixing states in individual particles. The mixing states of methylamine (MA)-, trimethylamine (TMA)-, and diethylamine (DEA)-containing particles were studied using a high-performance single particle aerosol mass spectrometer (HP-SPAMS) in Guangzhou, China, in January 2020. The sharp increase in TMA particles was found to be closely associated with the increase in the ambient relative humidity (RH), while the MA- and DEA-containing particles were not similarly influenced by the changes in the RH. The prominent enrichment of secondary oxygenated organics in DEA particles during the daytime was consistent with the active period of photochemistry, implying that the sharp decrease in DEA particles in the afternoon was likely due to photo-oxidation of the DEA. The number fraction (N f ) of DEA particles, the N f of the nitrate in the DEA particles, and the abundance of nitrate increased as the NO x content all increased during the nighttime, suggesting that the formation of DEA·HNO 3 salt was the dominant pathway of particulate DEA production. These results are consistent with our previous measurements in Nanjing, confirming the general and distinct mixing states of TMA and DEA particles. Positive matrix factorization analysis revealed that the total fraction of the more oxidized organics factor and the less oxidized organics factor were much higher in the DEA particles (26.9 %) than in the TMA particles (9 %), confirming the significant enrichment of oxygenated species in the DEA particles. The different mixing states of the amines revealed the unique response of each type of amine to the same atmospheric environment, and the prominent mixing states of the DEA with secondary oxygenated species suggest the potential role of DEA in tracing the evolution of organic aerosols., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Imidazoles (IMs) are potential contributors to brown carbon; they may notably contribute to climate radiative forcing. However, only a few studies have assessed the mixing state, seasonal and spatial distributions of IMs, and influencing factors for IM formation in urban aerosols. In this study, two single-particle aerosol mass spectrometers were employed to investigate the IM-containing particles in the urban areas of Beijing and Guangzhou, China. IM-containing particles were identified in the size range (d va ) of 0.2-2.0 μm, accounting for 0.7-21.7 % of all the detected particles. The number fractions of IM-containing particles in both cities were the lowest in winter and the highest in spring, probably owing to the difference in the abundance of precursors and the particle acidity. Majority of (60-80 % by number) the IM-containing particles were mixed with organic carbon (OC), with the lowest fractions found in summer. Although the number fractions of IM-containing particles in Beijing were generally higher (~1.5-3 times) than those in Guangzhou, the mixing states of the IM-containing particles at these two sites were only slightly different. Potassium-rich (K-rich) and potassium-sodium (KNa) particles were rarely found in Guangzhou; they accounted for ~15 % of the IM-containing particles in Beijing. Additionally, our results indicate that particles with higher acidity are favorable for IM formation. These findings help improving our knowledge of the mixing state, seasonal variation, and spatial distribution of IMs in urban aerosols, and the insights in influencing factors into IM formation provide valuable information for future studies of the atmospheric chemical processes associated with IMs., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)

With structural diversity of water-soluble polysaccharides, their precise quantitative analysis by phenol‑sulfuric acid method becomes more difficult and challenging. In this study, the quantification analysis of dextran and glucose in phenol sulfuric acid method was compared in this paper. When the concentration is below 90 μg/mL, the quantification of glucose is close to theoretical value, however, glucose derivatives have significantly different absorption. Later, quantitative factors of water-soluble polysaccharide in RID measurement were investigated. The optimum temperature was 40 °C and linear range was 0.3125-10.0 mg/mL in RID for dextrans (1.0-500 kDa) and glucose derivatives. Method validation studies of the RID method were further performed and compared to conventional phenol sulfuric acid method, which demonstrated that RID measurement is more reliable and satisfactory method. The intervention of water-soluble impurity in RID response should be well control below 6% (w/w). By comparison, the RID measurement could well alleviate drawbacks in phenol‑sulfuric acid method., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To investigate photochemical ozone (O 3 ) formation and provide localized control strategies, an intensive sampling of O 3 and its precursors (i.e. volatile organic compounds (VOCs) and nitrogen oxides (NO x = NO + NO 2 )) were conducted at an urban site in Leshan, Sichuan province during 4-13 August 2019. The mixing ratios of O 3 , total VOCs (TVOCs) and NO x were 40.0 ± 5.3, 22.5 ± 2.6 and 14.6 ± 3.8 ppbv, respectively (±95% confidence intervals). O 3 and its precursors existed a well negative correlation, indicating intensive local O 3 formation. To further explore the O 3 -precursors relationship and observation-oriented O 3 control strategies, a photochemical box model coupled with master chemical mechanism (PBM-MCM) was adapted. The relative incremental reactivity (RIR) calculated by model results showed that Leshan was in the VOCs-limited and O 3 production was most sensitive to alkenes. Moreover, O 3 isopleth diagram was drawn using the PBM-MCM simulation results and seven reduction scenarios were evaluated in Leshan. The reduction ratio of VOCs/NO x on 3:1 was proposed to be the best solution, which can be achieved effective reduction on local O 3 formation. At last, since VOCs were the key precursors of O 3 in Leshan, VOC sources and their potential contributions to O 3 formation were investigated by using the positive matrix factorization (PMF) model. Seven sources were identified, and traffic related emissions (including vehicle exhaust and gasoline evaporation, 29.9%) and fixed combustion (27.7%) had the large contribution to ambient VOCs. Among anthropogenic sources, fixed combustion and solvent usage in painting were the large contributors to O 3 formation, accounting for 30.9% and 18.3%, respectively, which should have high priorities on source reduction. This study provides scientific advices for future O 3 pollution control strategies in Leshan, which can be extended to other cities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Through hot water extraction, protein removal and chromatographic purification, DWPP-Is was found to be the major polysaccharide present in the stem of D. wardianum. The Mn and Mw of DWPP-Is were 29.0 kDa and 98.6 kDa, respectively. Furthermore, mannose and glucose were found to be the most abundant monosaccharides in DWPP-Is. Their backbones consist of (1 → 4)-β-d-Glcp and O-acetylated (1 → 4)-β-d-Manp, which are similar to the structures of other anti-tumour Dendrobium polysaccharides. The inhibition rate of DWPP-Is treatment on SPC-A-1 cells (2 mg/mL, 72 h) reached 56.0%. Intragastric administration of DWPP-Is on A549 tumour-bearing KM mice (10 mg/mL, 0.2 mL) exhibited similar inhibition ratios to that of erlotinib hydrochloride (2 mg/mL). Moreover, the highest inhibition was observed in P-CK treatment combined with DWPP-Is, reaching an inhibition rate of 23.4%. These results suggest that DWPP-Is has the potential to be a functional agent for lung cancer prevention., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: To observe the secondary prevention efficacy of subcutaneous immunotherapy in children with allergic rhinitis（AR） and cough variant asthma（CVA） and to analyze its effect on the levels of serum sIgG4, IL-27 and IL-33. Method: The clinical data of 112 children aged 5-12 years with AR and CVA were retrospectively analyzed and divided into control group（52 cases） and SCIT group（60 cases）. The patients were followed up for 3 years. The control group was received symptomatic treatment only, and the SCIT group was received SCIT on the basis of the control group. The numbers of cases of the two groups of children who produced new allergens and developed CA were analyze during the 3-year treatment. Changes in serum sIgG4, IL-27, IL-33 levels, TNSS, DCSS, NCSS, TRMS, TCMS, VAS score, and FEV1% before and after treatment were analyzed. Result: During the treatment, 4 patients（6.67%） in the SCIT group produced the new allergen, and 20 patients（38.46%） in the control group（χ²=16.73, P <0.05）. There were only 3 cases（5.00%） in the SCIT group, which developed into CA, while 15 cases（28.85%） in the control group. The difference between the groups was statistically significant（χ²=11.74, P <0.05）. Compared with baseline, serum levels of sIgG4 and IL-27 in both groups were significantly increased after 3 years of treatment（ P <0.05）, while serum levels of IL-33 were significantly decreased（ P <0.05）. After 3 years of treatment, serum levels of sIgG4 and IL-27 in the SCIT group were significantly higher than those in the control group, and serum levels of IL-33 were significantly lower than those in the control group（ P <0.05）. Compared with baseline, TNSS, DCSS, NCSS, TRMS, TCMS, VAS, and FEV1% in both groups were significantly improved at 1, 2, and 3 years of treatment（ P <0.05）. There was no significant difference in TNSS, DCSS, NCSS, TRMS, TCMS, VAS and FEV1% between the two groups at baseline（ P >0.05）, while after 1, 2 and 3 years of treatment the above indicators in the SCIT group were significantly better than those in the control group（ P <0.05）. Conclusion: SCIT treatment can prevent AR with CVA patients from producing new allergens and developing into CA, and improve serum sIgG4 and IL-27 and IL-33 levels., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

In this work, we analyzed freshly emitted particles from ship exhaust in the Guangzhou port region before and after the implementation of a clean fuel policy. We used a single particle aerosol mass spectrometer (SPAMS) to measure the changes in the chemical compositions of single particles and evaluate the role of V as a tracer for ship emissions. Particles from high sulfur fuel (S F ) oil (HS) combustion ships consisted of 54.8% elemental carbon-vanadium-sulfate (EC-V-S) and 25.0% vanadium-sulfate (V-S) particles, while particles from low S F oil (LS) combustion ships were composed of 38.7% organic carbon-sulfate (OC-S) and 28.6% elemental and organic carbon (ECOC) particles. The sulfate-containing particles exhibited a moderate decrease from 95% in HS emissions to 78% in LS emissions, which still suggests the dominant role of sulfate in LS emissions after the implementation of a clean fuel policy. The V-containing particles showed a sharp decrease from 67% in HS emissions to 14% in LS emissions along with the decrease in the relative peak area (RPA) of V, suggesting a remarkable reduction in V in ship exhaust. The count of V-containing particles in urban Guangzhou in June 2017 was generally ten times lower than that in June 2016, which was in accordance with the sharp decrease in V-containing particles in LS emissions rather than in HS emissions. Despite the decrease in V in source-oriented ship emitted particles, the ubiquitous distribution of V in particles from lower S F combustion ships suggests V is still effective as a tracer of ship emissions in port regions after the implementation of the clean fuel policy. Furthermore, the particles from LS emissions were investigated in comparison to those from gasoline vehicles (GV), diesel vehicles (DV) and coal combustion (CC) sources to better resolve ship-related particles in port regions., Competing Interests: Declaration of competing interest No conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The risk factors for multi-drug resistant infection (MDRI) in the pediatric intensive care unit (PICU) remain unclear. It's necessary to evaluate the epidemiological characteristics and risk factors for MDRI in PICU, to provide insights into the prophylaxis of MDRI clinically., Methods: Clinical data of 79 PICU children with MDRI were identified, and 80 children in PICU without MDRI in the same period were selected as control group. The related children's characteristics, clinical care, microbiologic data, treatments provided, and outcomes of the patients with were reviewed and collected. Univariate and multivariate logistic regression analyses were performed to identify the potential risks of MDRI in PICU., Results: Of the diagnosed 79 cases of MDRI, there were28 cases of CR-AB, 24 cases of MRSA, 22 cases of PDR-PA,3 cases of VRE and 2 cases of CRE respectively. Univariate analyses indicated that the length of PICU stay, the duration of mechanical ventilation > 5 days, parenteral nutrition, coma, urinary catheter indwelling, invasive operation, 2 or more antibiotics use were associated with MDRIs (all p < 0.05); The logistic multiple regression analyses indicated that coma, parenteral nutrition, 2 or more antibiotics use and the duration of mechanical ventilation > 5 days were independent risk factors associated with MDRI (all p < 0.05)., Conclusions: This present study has identified several potentially modifiable risk factors for MDRI in PICU, it's conducive to take appropriate measures targeting risk factors of MDRI for health care providers to reduce MDRI.

Raloxifene (RXF) is a hormone-like medication used for treating postmenopausal osteoporosis and estrogen-dependent breast cancer, yet associated with bad low bioavailability due to poor solubility. This study was intended to develop cyclodextrin/chitosan nanoparticles (ccNPs) for oral delivery of RXF in order to enhance the oral bioavailability. RXF-loaded ccNPs (RXF-ccNPs) were prepared by cyclodextrin inclusion followed by complexation with chitosan. RXF-ccNPs were fully characterized by particle size, morphology and in vitro drug release. The oral delivery efficacy and transepithelial transport potential were evaluated by pharmacokinetics, in situ single-pass intestinal perfusion, cellular uptake and ex vivo imaging. The resulting RXF-ccNPs were around 165 nm in particle size with a narrow distribution. The oral bioavailability of RXF was enhanced by 2.6 folds through ccNPs compared to RXF suspensions in rats. It was shown that RXF-ccNPs could improve the intestinal permeability of RXF, increase the cellular uptake of RXF and facilitate its transport across the absorptive epithelia. The results indicate that our developed ccNPs based on sulfobutylether-&beta;-cyclodextrin and oligochitosan are a promising vehicle to orally deliver poorly water-soluble drugs over and above RXF.

Background: Nursing-sensitive indicators are considered effective tools for improving the quality of care in hospitals. However, these have not been used in paediatric intensive care units (PICUs) in China., Aim: To develop nursing-sensitive indicators for PICUs and to assess the quality of nursing in PICUs in China based on the nursing-sensitive indicators., Design: Multi-centre, cross-sectional study., Methods: Structure, process and outcome indicators were developed and measured from 1 January to 31 March 2014 in seven PICUs in China., Results: The structure indicators showed that one nurse cared for an average of 2·8 patients in a PICU, and 44% of nurses had a bachelor's degree. The process indicators revealed that hand-washing compliance varied across PICUs, whereas pain management and physical restraint have not been adequately addressed in China. The outcome indicators revealed that the incidence rates of ventilator-associated pneumonia and central-line-associated blood stream infections were 2·96 and 0·7, respectively, per 1000 device days. Patients were intubated for a total of 4392 mechanical ventilator days, and 32 patients (7·29‰) had an unplanned extubation. Nurses were moderately satisfied in their jobs (3·1 ± 0·3), and parents reported that nurses provide high quality of care., Conclusions: This study developed and used nursing-sensitive indicators to assess the quality of nursing in PICUs in China, which provided a reference for national and international comparisons of nursing quality in PICUs. Nursing staffing levels and education should be improved. Pain management and physical restraints should be regulated in China's PICUs. Nurse managers need to explore staff attitudes towards implementation of family-centred care. The development of a national database of nursing quality indicators can contribute to quality and safety improvement., Relevance to Clinical Practice: This study developed a set of nursing-sensitive indicators, and these indicators were used to assess and improve the quality of nursing in PICUs., (© 2016 British Association of Critical Care Nurses.)

This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

Objective: To analyze the incidence and treatment of Clostridium difficile infection (CDI) in pediatric patients with antibiotic-associated diarrhea (AAD)., Method: Clinical data of totally 577 pediatric patients with AAD seen from January 2012 to January 2014 were collected; those children were divided according to age into 4 groups, 0.25 -1 year, >1 -4 years, >4 -12 years and >12 -18 years old groups, and 220 healthy children were enrolled as controls. CDI was tested by C. Diff Quik Chek Complete (QCC) and BD GeneOhm™ C. Diff Assay (BD-PCR) in all children, and the CDI incidence of four groups was added up. All pediatric patients with AAD were divided into mild, general and severe type according to different symptoms of diarrhea, and grading treatment, the general type and severe type of CDI children were treated with metronidazole and (or) vancomycin, afterwards, the results of grading treatment were analyzed., Result: The number of pediatric patients with AAD were 178, 177, 132 and 90 in 0. 25 - 1 year, > 1 -4 years, > 4 - 12 years and > 12 - 18 years old group, respectively. The positive rate of CDI (22. 0% (39/177)) in > 1 -4 years old AAD patients was very significantly higher compared to the controls (4% (4/91), P < 0. 001), the rate of CDI (21. 2% (28/132)) in > 4 - 12 years old AAD pediatric patients was significantly higher compared to the controls (4% (2/53), P = 0. 004), the rates of CDI in 0. 25 - 1 year and > 12 - 18years old AAD groups were not significantly different from that of the controls (P >0. 05). There were 285 mild type AAD children (no CDI children), 176 general type AAD children (including 47 CDI children), and 116 severe type AAD children (including 81 CDI children). After grading and symptomatic treatment, there were 16 recurrent diarrhea in 128 CDI patients (severe type AAD), and the rest recovered. Two cases were transferred for referral treatment, 2 cases died, and the rest 12 recurrent diarrhea children fully recovered after administration of metronidazole, vancomycin, probiotics and symptomatic treatment., Conclusion: The > 1 -12 years old AAD children had higher CDI rate than healthy children; administration of metronidazole and (or) vancomycin was effective for CD infection.

Fractional derivative has a history as long as that of classical calculus, but it is much less popular than it should be. What is the physical meaning of fractional derivative? This is still an open problem. In modeling various memory phenomena, we observe that a memory process usually consists of two stages. One is short with permanent retention, and the other is governed by a simple model of fractional derivative. With the numerical least square method, we show that the fractional model perfectly fits the test data of memory phenomena in different disciplines, not only in mechanics, but also in biology and psychology. Based on this model, we find that a physical meaning of the fractional order is an index of memory.

A facile and green method was developed to synthesize the graphene-carbon nanotubes (Gr-CNTs) nanocomposite with a sandwich lamination structure. Pt nanoparticles were loaded on the as-synthesized Gr-CNTs nanocomposite to prepare an electrochemical sensor for determining bisphenol A (BPA) in thermal printing paper. The electrochemical behavior of BPA on the Pt/Gr-CNTs nanocomposite was investigated by cyclic voltammetry (CV) and chronocoulometry (CC). The direct determination of BPA was accomplished by using differential pulse voltammetry (DPV) under optimized conditions. The oxidation peak current was proportional to the BPA concentration in the range from 6.0 × 10(-8) to 1.0 × 10(-5) M and 1.0 × 10(-5) to 8.0 × 10(-5) M with a correlation coefficient of 0.987 and 0.998, respectively. The detection limit was 4.2 × 10(-8) M (S/N = 3). The fabricated electrode showed good reproducibility, stability and selectivity. The proposed method was successfully applied to determine BPA in thermal printing papers samples and the results were satisfactory.

Poly(l-arginine)/graphene composite film modified electrode was successfully prepared via a facile one-step electrochemical method and used for simultaneous determination of uric acid (UA), xanthine (XA) and hypoxanthine (HX). The electrochemical behaviors of UA, XA and HX at the modified electrode were studied by cyclic voltammetry and differential pulse voltammetry (DPV), and showed that the modified electrode exhibited excellent electrocatalytic activity toward the oxidation of the three compounds. The calibration curves for UA, XA and HX were obtained over the range of 0.10-10.0, 0.10-10.0 and 0.20-20.0 μM by DPV, respectively and the detection limits for UA, XA and HX were 0.05, 0.05 and 0.10 μM (S/N=3), respectively. With good selectivity and high sensitivity, the modified electrode has been applied to simultaneous determination of UA, XA and HX in human urine with satisfactory result., (Copyright © 2012 Elsevier B.V. All rights reserved.)