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A new method was proposed for point-of-care testing (POCT) of immunosuppressants in blood using thin-layer paper spray ionization and a miniature mass spectrometer. The aluminum thin-layer plate was used as paper spray substrate, and cut into an equilateral triangle. Aliquots of 10 μL blood sample were loaded on the aluminum thin-layer plate, and then 20 μL methanol was dropped as elution/spray solvent. The tip of the triangular plate was placed 1.0 cm in front of the discontinuous atmospheric pressure interface (DAPI) of the miniature mass spectrometer. When the spray voltage was applied, the sample was eluted from the triangular plate and formed paper spray ionization at the tip. Coupled with the miniature mass spectrometer, five immunosuppressants were detected under negative ion mode. The precursor ions ［M-H］- of tacrolimus, sirolimus, everolimus, ciclosporin A, and mycophenolic acid are m/z 802.6, 912.6, 957.1, 1 200.8, 319.1, and product ions are m/z 560.2 and 604.3, m/z 590.3 and 321.2, m/z 590.3 and 365.2, m/z 1 088.8, m/z 287.4 and 275.1, respectively. Based on the observed signal-to-noise ratio (S/N) of the most intense tandem mass spectrometry (MS/MS) fragment peaks and using the S/N=3 and 10 as the criteria, the limits of detection (LODs) and quantitation (LOQs) are estimated to be 0.5-5 mg/L and 1-10 mg/L, respectively. The internal standard method was used for quantitative analysis, and indapamide was used as the internal standard compound. Sufficient linearity for each analyte is obtained with the correlation coefficients (r) greater than 0.99. The proposed method displays good recoveries in the range of 91.0%-114.3% with the relative standard deviations (RSDs) less than 8.4%. Moreover, the developed method was used for the analysis of blood samples, which spiked with tacrolimus, sirolimus, everolimus, cyclosporine A and mycophenolic acid at the concentration of 100 mg/L. The analytical results demonstrated the consistency between the proposed method and the traditional liquid chromatography-mass spectrometry (LC-MS) method. The entire analysis procedure can be completed within 1 min. The proposed method is simple, fast, accurate, efficient, and suitable for POCT of immunosuppressants in blood.

BackgroundIn recent years, the rising number of e-cigarette users among adolescents and the surging cases of lung injury related to e-cigarette use have attracted the attention of researchers in various fields.ObjectiveTo identify the research hotspots and trends of e-cigarette or vaping product use associated lung injury (EVALI) worldwide from 2013 to 2022 by bibliometric and visual analysis. MethodsWeb of Science Core Collection was selected to obtain literature related to EVALI from 2013 to 2022 across the world, statistics were calculated by country/region, institution, author, journal, cited literature, keyword, etc. CiteSpace 6.2.R1 was used for visual analysis to draw diagrams of publication trend, author cooperation network, co-citation clustering time distribution, and keyword cluster. ResultsA total of 888 EVALI-related papers published between 2013 and 2022 were retrieved. The number of publications was gradually increased, with a significant increase in 2020 and a decrease from 2021, but the number of citations was increased year by year. The most active country was the United States (631 articles). European and American countries cooperated closely and the centrality was prominent. Among the publishing institutions, the University of California system topped the list with 103 articles. Rahman I (27 articles) published the most articles and had a high degree of centrality; Goniewicz M L was the most cited author; and the network analysis diagram showed relatively weak collaboration between authors. The American Journal of Respiratory and Critical Care Medicine was the journal with the highest number of publications (94 articles). The top 5 cited articles were all cited more than 300 times. The leading high-frequency keywords of EVALI-related studies were nicotine (149 times), exposure (118 times), and oxidative stress (80 times). The cluster of key nodes in the co-citation network and the clustering time distribution diagram indicated youth e-cigarette addiction received widespread attention from society. From the top 25 keywords with the strongest bursts, the focus of research on the pathogenesis of EVALI gradually shifted from the oxidative stress damage associated with e-cigarette vapor to the oxidative effect of flavoring chemicals in the process of lung injury. The current research interests in this field were mainly the mechanisms of various chemicals in e-cigarettes and the heating elements that led to damage to the lungs. ConclusionEVALI is receiving continuous attention from researchers in government, medical institutions, and other organizations. A variety of e-cigarette ingredients such as flavoring chemicals may lead to varying degrees of cytotoxicity, inflammation, and lung damage. However, the pathophysiology of EVALI remains unclear. In the future, more Chinese scholars should be encouraged to participate in this field.

Based on the selective quenching effect of the flavonoid rutin on the fluorescence of carbon dots prepared by asparagine pyrolysis, a method for rapid detection of rutin content in the flower buds of Sophora japonica by using chitosan-based carbon dot paper chip was developed. A filter paper was immersed in the casting solution of carbon dots and chitosan. After drying, a carbon dot chitosan film was formed on the surface of the filter paper, so that the chitosan-based carbon dot paper chip was obtained. After samples were dripped on the chip, chromogenic reaction occurred uniformly within a limited region, and pictures were taken under an ultraviolet (UV) lamp at 365 nm for analysis of the red (R), green (G), and blue (B) values of the colored spots in order to optimize the preparation conditions and detection conditions. The results showed that the optimal conditions were as follows: chitosan concentration of 20 mg/mL, carbon spot concentration of 1.0 mg/mL, 50% ethanol as sample solvent, and reaction time of 20 min. Under these conditions, the difference (ΔG) in G-value between sample and solvent spots had a linear relationship with rutin concentration (C) in the range of 4 to 120 mg/mL. Using this method, the average contents of rutin in the flower buds of S. japonica from three batches were determined to be 23.85%, 22.83% and 20.30%, the average relative standard deviations (RSDs) were 6.1%, 5.6% and 6.7%, and the recoveries were 91.27% to 107.5%, which were close to the results of high performance liquid chromatography (HPLC). The proposed method is simple and rapid, and can be used for rapid on-site determination of rutin content in the flower buds of S. japonica.

Results of academic research require publication and need to be reviewed by peers before they can contribute to the existing body of knowledge. Among the various means of publishing research findings, researchers may, according to past academic practices, first present their research results in conferences, seminars or symposiums, and then submit their results to journals for publication. Hence, the issue of “extended publication”, where conference papers are revised and submitted to journals, has gained attention in the library and information science community. This study collected public documents on the Internet and applied document analysis to examine the ethical considerations regarding such extension practice. First, this research reviewed the basic principles of research integrity and responsible behavior. Secondly, this research listed several types of violation related to research paper writing and submission, and studied the guidelines established by both domestic and foreign academic organizations, publishers, and journals. The findings of the research were used to provide specific recommendations on the best practices for extending conference papers to journal articles.

“Lab on paper” is a paper-based microanalytical system with unique advantages such as high sensitivity, low cost, portability, and mass production, which breaks through the limitations of traditional detection technologies and shows great potential in the field of rapid on-site food detection. In this paper, the typical “labs on paper”, including chromatographic paper, chemical test chip, lateral flow assay (LFA), microfluidic paper-based analytical devices (μPADs), and synthetic biological paper, are systematically reviewed. Special emphasis is put on the application of “lab on paper” in the field of food detection. Finally, the advantages, challenges, and future prospects of paper-based analytic methods are discussed, which may provide theoretical support for better application of “lab on paper” in the field of food detection.

BackgroundBy analyzing the publication of scientific and technological papers of the provincial centers for disease control and prevention (CDCs) in China, we can understand their scientific research strength, dominant disciplines, research hotspots, and talent development, which is conducive for further optimizing the scientific research construction of the disease control system.ObjectiveTo conduct a bibliometric analysis and draw a visual map of the Chinese Science Citation Database (CSCD) sourced papers published by 31 provincial CDCs in China from 2011 to 2020, to understand the scientific research status of China's provincial CDC system in the past ten years.MethodsIn April 2021, China National Knowledge Infrastructure was used to retrieve CSCD sourced papers published by 31 provincial CDCs (excluding Taiwan Province, Hong Kong and Macau Special Administrative Regions) in China as the primary unit from 2011 to 2020, and finally 5231 CSCD papers were included. Bibliometric analysis indicators include number of CSCD papers published and financial support rate, proportion of CSCD papers to total Chinese papers, distribution of CSCD papers published in high-volume journals, and number of papers for a specific CDC that their first authors affiliated with. Citespace 5.8.R1 software was used to draw author's cooperation network map, keyword co-occurrence map, keyword clustering information table, and keyword emergence map.ResultsThe number of CSCD papers published every year showed a stationary trend, and the total funding rate was 61%, showing an year-by-year upward trend (increased from 49.3% in 2011 to 68.7% in 2020). Jiangsu Province, Fujian Province, and Beijing CDCs ranked the top three in the total number of CSCD papers contributed by a specific CDC. The Chinese Journal of Epidemiology, Chinese Journal of Public Health, Chinese Journal of Zoonoses, Chinese Journal of Preventive Medicine, and Chinese Journal of Endemic Diseases were the top five high-volume journals. The top three authors of CSCD papers (counted as co-authors) were Xu Bianli of Henan Provincial Center for Disease Control and Prevention (110 papers), Yan Yansheng of Fujian Provincial Center for Disease Control and Prevention (72 papers), and Wang Quanyi of Beijing Center for Disease Prevention and Control (71 papers), and they studied the epidemiology of parasitic diseases and infectious diseases, the prevention and treatment of natural epidemic diseases and AIDS, and the epidemiology of infectious diseases, respectively. The keyword co-occurrence map showed that AIDS, zoonotic diseases, hand-foot-mouth disease, etc. (frequency ≥90) were the key research directions of provincial CDCs in the past ten years. The keyword clustering categories were closely related, although there were subtle differences, the topics focused on virus and chronic disease research. The keyword emergence results suggested that the frontiers of research had gradually shifted from infectious diseases such as enterovirus, hantavirus, and Zika virus to food-borne diseases and chronic non-communicable diseases such as tumors and senile diseases over time.ConclusionThe number of papers issued by the provincial CDCs in China in the past ten years has shown an overall steady and rising trend. The leading themes of researchers and institutions are infectious diseases, parasitic diseases, etc., while food-borne diseases and elderly diseases are the hot frontiers.

An efficient surface enhanced Raman scattering(SERS)substrate was prepared by screen printing silver ink on drawing paper, white card paper and coordinate paper. The results showed that silver film/drawing paper represented the best SERS activity, followed by silver film/white card paper and silver film/coordinate paper. The minimum detection limits for crystal violet were 10-8, 10-7 and 10-7 mol·L-1, respectively. In addition, ten different positions were randomly selected on the same silver film/drawing paper surface, and the relative standard deviation values of the peak intensitiesat 913, 1 179 and 1 620 cm-1 were 13.2%, 12.5% and 10.6%, respectively, which indicated outstanding uniformity.

This study used bibliometrics to analyze the characteristics of funded papers in the social sciences in Taiwan from 2015 to 2019, including the number of funded papers, funded paper ratio, document types, fields, type of publishing organizations, journal impact, and paper citation impact. The results indicate that the number of funded papers and the funded paper ratio of SSCI papers from Taiwan have both increased. In addition to articles and reviews, conference papers are a major type of funded paper for local SSCI papers. In terms of fields, the nontraditional social sciences, such as environmental sciences, psychiatry, and public/environmental & occupational health, have a particularly high funded paper ratio. However, the number of funded papers and funded paper ratio is the highest in the field of education & educational research. The fields of economics, management, and business have a large number of funded papers but a low funded paper ratio. Universities are the main funded institutions, but hospitals have the highest funded paper ratio. Funded papers tend to have higher paper citation impacts. Therefore, funding positively affects the productivity and impact of SSCI papers from Taiwan. (Article content in Chinese with English extended abstract)

BackgroundThe COVID-19 pandemic hints at the importance of modernizing disease control system. To understand the scientific research strength of our country's disease control system in recent years is conducive to formulating more targeted policies or measures to promote the modernization of the disease control system.ObjectiveTo understand the scientific research strength and research hotspots of China's provincial-level centers for disease control and prevention (CDCs) from 2011 to 2020, and provide evidence for the development of scientific research work, discipline construction, and talent team construction in CDCs in the future.MethodsThe Science Citation Index Expanded (SCIE) and Social Science Citation Index (SSCI) of the Web of Science Core Collection were used to retrieve SCI-indexed English papers published by 31 provincial CDCs (excluding Taiwan Province, Hong Kong and Macau Special Administrative Regions) in our country from 2011 to 2020, and to screen literature with provincial CDCs as the first affiliation for bibliometric analysis and visual analysis. Bibliometric analysis included the SCI-indexed publications of different provincial CDCs (as co-affiliation and the first affiliation), the number of SCI-indexed papers published by provincial CDCs (as the first affiliation) and funding rates by years, the high-frequency authors of SCI-indexed papers published by provincial CDCs (as the first affiliation) and their distribution, and the characteristics of the journals. Visual analysis software Citespace 5.8.R1 was used to draw keyword co-occurrence maps, cluster information tables, and emergence maps to provide information on research hotspots and their evolution.ResultsFrom 2011 to 2020, the number of SCI-indexed papers from 31 provincial CDCs was 8420 (including co-affiliation), of which 2060 papers listed provincial CDCs as the first affiliation. The provincial CDCs of Zhejiang, Jiangsu, Shanghai, Beijing, Shandong, and Guangdong were the leading six institutes in terms of the total number of SCI-indexed papers contributed as co-affiliation or the first affiliation. There was a large gap in the total number of SCI-indexed papers among the provincial CDCs. The highest total number of SCI-indexed papers contributed by provincial CDCs as the first affiliation was Zhejiang CDC (448 papers), while the lowest number was Xinjiang CDC (only 1 paper). From 2011 to 2020, the total number of SCI-indexed papers contributed by the 31 provincial CDCs as the first affiliation showed an overall increasing trend. Except for 2011, which was 63.1%, the funding rates in other years exceeded 70%. In terms of high-frequency authors, 13 first authors published ≥10 SCI-indexed papers: Zhang Yingxiu from Shandong CDC had the highest number of SCI-indexed papers (47), followed by Hu Yu from Zhejiang CDC. Zhejiang, Jiangsu, Beijing, Guangdong, Shanghai, and Shandong still ranked the top six of ≥4 first authored-SCI papers. In terms of journal characteristics, the top 20 journals with the highest number of SCI papers published a total of 862 papers, accounting for 41.8% (862/2060), and PLOS ONE ranked the first (188 papers). The research hotspots were mainly concentrated in the fields of infection, child health, and epidemiology. The main keywords of the first three cluster categories were related to the research fields of adolescent overweight and obesity, HIV, and vaccine immunity. The results of keyword emergence showed that research hotspots shifted from overweight, obesity, and body mass index to antibodies, vaccines/vaccination, and cohorts.ConclusionThe past ten years have witnessed increasing numbers of SCI-indexed papers published by provincial CDCs in our country and a stubbornly high funding rate. However, the gap among the provincial CDCs is still large seeing that economically developed eastern provincial CDCs published more SCI-indexed papers. Research hotspots have gradually shifted from overweight, obesity, and body mass index to antibodies, vaccines/vaccination, and cohorts.

Naturally-occurring precipitate of traditional Chinese medicine (TCM) is generally considered to be a common phenomenon. The formation of naturally-occurring precipitate originates from the interactions among different chemical components during the decoction process. Previous literature has reported the existence of naturally-occurring precipitate in Sini decoction. In this study, seven pairs of acid-base non-covalent complexes in Sini decoction were characterized using cold spray ionization-mass spectrometry (CSI-MS). The CSI device was built in house, where a stream of nitrogen gas was cooled by liquid nitrogen and used as the sheath gas, providing low-temperature ionization conditions for the MS analysis of the acid-base non-covalent complexes. The gas pipeline was equipped with a valve to regulate the nitrogen flow rate. Data acquisition was carried out using a quadrupole/Orbitrap high-resolution mass spectrometer operated in both full-scan MS and collision-induced dissociation MS/MS modes. Experimental results showed that the seven pairs of acid-base non-covalent complexes were unequivocally observed in positive and negative ionization modes. Mass spectrometric responses for each acid-base non-covalent complex varied with different chemical structures, binding abilities and ionization efficiencies. A representative pair of acid-base non-covalent complex (enoxolone/benzoylmesaconine) was selected to investigate the influence of the acid-base concentration ratio (3∶1, 2∶1, 3∶2, 1∶1, 2∶3, 1∶2, 1∶3) on the binding stoichiometry. The enoxolone/benzoylmesaconine complexes with the binding ratios of 1∶1, 1∶2, 2∶1 were observed, among which the mass spectrometric peak of the 1∶1 binding ratio was the most intensive. The non-covalent interactions of the representative enoxolone/benzoylmesaconine complex were analyzed using isothermal titration calorimetry (ITC) and computational chemistry. The thermodynamic parameters were obtained in the ITC experiment. In comparison with entropy change, the contribution of enthalpy change to Gibbs free energy was more significant, indicating that Van der Waals force and hydrogen bonding might be the main driving force in the formation of acid-base non-covalent complexes. This result was further confirmed by the docking model and simulation results of computational chemistry. Multiple hydrogen bonds derived from the interactions between specific atoms locating in the acid and base compounds promoted the self-assembly process. Moreover, Van der Waals attraction or repulsion force was generated between the C and H atoms at different positions, which in conjunction with hydrogen bonding interaction drove the formation of the acid-base non-covalent complexes. This study provides theoretical foundation and technical instruction for exploring the formation mechanism of naturally-occurring precipitate in Sini decoction.