Research hotspots and development trends in volume management of peritoneal dialysis patients: a bibliometrics and visual analysis up to 2022

OBJECTIVES

Among different renal replacement therapies (RRTs), peritoneal dialysis (PD) is a family based treatment method with multiple advantages, which allowing patients to maintain autonomy, avoiding frequent hospital visits, and preventing the spread of the disease virus. To visually analyze the literatures related to volume management of PD patients through bibliometric methods, to explore research hotspots and development trends in this field.

METHODS

The relevant literatures of PD patient volume management in the Web of Science core collection database were retrieved with the terms of peritoneal dialysis, volume management, capacity management, fluid status, and volume overload. The retrieval time was from the establishment of the database to October 2022. CiteSpace 6.1.R3 software was used to visually analyze Country, Institution, Author, Keyword, and draw keyword clusters and keyword emergence maps.

RESULTS

A total of 788 articles were included in the analysis, and the annual number of papers was on the rise, with the American, China, and Brirain in the top three, and Peking University and University College London in the top. Keywords cluster analysis showed 11 clusters. In the keyword emergence analysis, the keywords with higher emergence intensity rank are continuous cyclic peritoneal dialysis, ambulatory peritoneal dialysis, and icodextrin. The current research hotspots and trends are in the evaluation of peritoneal dialysis patients' volume status, the selection and adjustment of dialysis prescriptions, and adverse health outcomes.

CONCLUSION

The research on peritoneal dialysis volume management in China started late, but it has developed rapidly, and has a firm grasp of current research hotspots. However, there is less cooperation with other countries, so international exchanges and cooperation should be strengthened. At present, the volume assessment methods and dialysis modes are still the research hotspots, paying more attention to the adverse health outcomes of patients.

The 'whole landscape' of research on systemic sclerosis over the past 73 years

OBJECTIVE

This study aimed to analyse existing research on systemic sclerosis (SSc) conducted over the past 73 years to develop an essential reference for a comprehensive and objective understanding of this field of inquiry.

METHODS

Using the Web of Science Core Collection, PubMed, and Scopus databases as data sources for the bibliometric analysis, we searched for published literature related to SSc over the past 73 years. The Bibliometrix package was used to analyse key bibliometric indicators, such as annual publication volume, countries, journals, author contributions, and research hotspots.

RESULTS

From 1970 to 2022, the number of SSc articles steadily increased, reaching its peak in 2020-2022, with approximately 1200 papers published in each of these three years. Matucci-Cerinic et al.'s team published the most articles (425). The United States (11,282), Italy (7027), and France (5226) were the most predominant contexts. The most influential scholars in the field were Denton, Leroy, Steen, and Khanna, with H-indices of 86, 84, and 83, respectively. Arthritis and Rheumatism was the most influential journal in this field (H-index 142). High-frequency keywords in the SSc field included fibrosis (738), inflammation (242), vasculopathy (145), fibroblasts (120), and autoantibodies (118) with respect to pathogenesis, and interstitial lung disease (ILD, 708), pulmonary arterial hypertension (PAH, 696), and Raynaud's phenomenon (326) with regards to clinical manifestations.

CONCLUSION

In the past three years, SSc research has entered a period of rapid development, mainly driven by research institutions in Europe and the United States. The most influential journal has been Arthritis and Rheumatism, and autoimmune aspects, vasculopathy, fibrogenesis, PAH, and ILD remain the focus of current research and indicate trends in future research.

Bibliometric analysis of biochar-based organic fertilizers in the past 15 years: Focus on ammonia volatilization and greenhouse gas emissions during composting

Biochar-based organic fertilizer is a new type of ecological fertilizer formulated with organic fertilizers using biochar as the primary conditioning agent, which has received wide attention and application in recent years. This study conducted a comprehensive bibliometric analysis of the main hot spots and research trends in the field of biochar-based organic fertilizer research by collecting indicators (publication year, number, prominent authors, and research institutions) in the Web of Science database. The results showed that the research in biochar-based organic fertilizer has been in a rapid development stage since 2015, with exponential growth in publications number; the main institution with the highest publications number was Northwest Agriculture & Forestry University; the researchers with the highest number of publications was Mukesh Kumar Awasthi; the most publications country is China by Dec 30, 2022. The hot spots of biochar-based organic fertilizer research have been nitrogen utilization, greenhouse gas emission, composting product quality and soil fertility. Biochar reduces ammonia volatilization and greenhouse gas emissions from compost mainly through adsorption. The results showed that adding 10% biochar was an effective measure to achieve co-emission reduction of ammonia and greenhouse gases in composting process. In addition, biochar modification or combination with other additives should be the focus of future research to mitigate ammonia and greenhouse gas emissions from composting processes.

Heading towards carbon neutrality: how do marine carbon sinks serve as important handle for promoting marine ecological civilization construction?

As an efficient long-term carbon sink, marine carbon sinks and the associated carbon sink effects, technology, accounting and trading market construction warrant investigation across various disciplines. However, information on the interrelationships and their development over time with respect to the research conducted in China is limited, affecting the ability to drive research directions and optimize continued advancement in this field. Therefore, in this study, we aimed to understand the current situation of marine carbon sink research in China to promote a deeper level of scientific development based on the research literature related to marine blue carbon sinks in the core databases of the China National Knowledge Internet (CNKI) and Web of Science (WOS). We used bibliometric tools in the Citespace software to quantitatively compare and analyse the main characteristics of marine blue carbon sink research including publication volume, time, journals, authors and institutions. We also explored the popular research topics, frontier areas, and theme evolution trends through keyword clustering and emergent and co-occurring knowledge maps. The key recommended research directions for ocean carbon sinks are: (1) to promote the unified carbon sink market research of land and sea integration through multidisciplinary and cross-disciplinary research; (2) to achieve new breakthroughs in ocean carbon sinks with the support of coastal wetlands and seawater offshore aquaculture environments; (3) to explore the protection provided by ocean carbon sinks with a comprehensive eco-compensation mechanism; (4) to improve the application of marine carbon sinks by taking the theory and technological innovation research related to marine carbon sinks as the guide. Ultimately, our work helps characterise the current situation of marine carbon sink research, promote the research in this field to a deeper level of development and provide reference for subsequent scholars to carry out related research.

Research trends and frontier hotspots of TRPV1 based on bibliometric and visualization analyses

Background

Transient receptor potential vanilloid type1 (TRPV1) is a non-selective cation channel with multiple activation mechanisms, which has received increasing attention since it was first cloned in 1997.

Methods

We used bibliometric and visualization analyses to evaluate the theme trends and knowledge structure of TRPV1 research-papers on TRPV1 from 2002 to 2022 obtained from the Web of Science Core Collection. VOSviewer and CiteSpace were used to analyze authors, institutions, countries, co-cited references, and keywords.

Results

A total of 7413 papers were included. The main research area of TRPV1 was neuroscience; the most published country was the United States, and the University of California, San Francisco, had the highest centrality. Two major collaborative sub-networks were formed between the authors. The distribution of keywords shows that TRPV1 was initially studied extensively, and the recent studies focused on TRPV1 structure and diseases. "Oxidative stress," "TRPV1 structure," "cancer," and "model" have been the research hotspots in recent years.

Conclusions

This research provides valuable information for the study of TRPV1. Disease research was focused on pain, cancer, and neurodegenerative diseases. Both agonists and antagonists of TRPV1 are gradually being used in clinical practice, and acupuncture was effective in treating TRPV1-mediated inflammatory pain. TRPV1 is involved in classical endogenous cannabis system signaling, and new signaling pathways continue to be revealed.

Bibliometric analysis and research trends of artificial intelligence in lung cancer

Background

Due to the rapid advancement of technology, artificial intelligence (AI) has become extensively used for the diagnosis and prognosis of various diseases, such as lung cancer. Research in the field of literature has demonstrated that artificial intelligence (AI) can be valuable in the timely detection of lung cancer and the formulation of an effective treatment plan. This study aims to conduct a bibliometric analysis to examine and illustrate the specific areas of focus, research frontiers, evolutionary processes, and trends in existing research on artificial intelligence in the context of lung cancer.

Methods

Publications on AI in lung cancer were selected from the SCIE and ESCI indexes on September 19, 2023. The examination of nations, academic publications, organizations, writers, citations, and terms in this domain was visually analyzed with InCites and VOSviewer.

Results

In this study, a total of 4275 publications were selected and analyzed. Artificial intelligence-related lung cancer publications have increased significantly in the last 5 years. China and the USA have contributed the most to the literature in this field (1418 publications with 13.92 citation impacts and 1117 publications with 37.34 citation impacts, respectively). The institution with the highest contribution was "Chinese Academy of Sciences," with 118 publications and 29.09 citation impacts. Among the research categories, "Radiology, Nuclear Medicine & Imaging", "Oncology", and "Engineering, Biomedical" were in first place.

Conclusion

The USA and China have always been leaders in this field and will continue to be for some time. Research in countries such as the Netherlands is increasing. However, research collaboration has to be strengthened in developing countries.

A bibliometric and knowledge-map analysis of bispecific antibodies in cancer immunotherapy from 2000 to 2023

Background

Bispecific antibody (BsAb)-based cancer immunotherapy has provided new avenues for the treatment of various malignancies. The approval of Blinatumomab has encouraged further investigation into these treatments, and a series of preclinical and clinical trials have been conducted, together with the publication of numerous articles. Here, the knowledge structure of BsAb-based cancer immunotherapy is summarized using bibliometric analysis to provide in-depth insight into current research trends and foci.

Methods

The studies included in the bibliometric analysis of BsAbs in cancer immunotherapy were retrieved from the online Web of Science Core Collection (WOSCC) database on April 16th, 2023. Visualization analysis was performed with the help of CtieSpace (version 6.2.2.msi [64-bit]), VOSviewer (version 1.6.19), R (version 4.2.1), and the Bibliometric analysis platform (R-based online data processing tool).

Results

A total of 1750 papers were identified. Analysis of annual publications and total citations indicated that publications have increased steadily over the past few decades. The USA, followed by Germany, had largest number of publications, making significant contributions to the field. The Memorial Sloan Kettering Cancer Center received the highest number of citations (n = 3769). However, its collaboration and cooperation with different institutions require further strengthening. MAbs and Clinical Cancer Research published the most papers, while Blood and Cancer Research were the most commonly co-cited journals. DM Goldenberg from the USA published the most articles with the highest H-index (34), and the most co-cited author (2137 citations) was PA Baeuerle; both these authors have distinguished achievements in this field. Analysis of co-cited references and keywords showed that the hotspots and research focus on the use of BsAbs for solid tumors have increased rapidly while the application of BsAb immunotherapy in hematologic malignancies has expanded significantly. The hot topics in the field included cytokine release syndrome, the efficacy and safety of BsAbs, resistance mechanisms, and the exploration and optimization of combination therapies.

Conclusion

Cancer immunotherapies based on BsAbs are a hot topic in research. Current studies focus on the construction and optimization of BsAb structure, as well as their combination with other treatment modalities to improve their efficacy and overcome resistance. Furthermore, it is expected that the ongoing investigation of BsAb-based immunotherapy for solid tumors will bear fruit with significant clinical application prospects in the near future.

Bibliometric analysis of papers on antibiotic resistance genes in aquatic environments on a global scale from 2012 to 2022: Evidence from universality, development and harmfulness

Antibiotic resistance genes (ARGs), emerging pollutants, are widely distributed in aquatic environments, and are tightly linked to human health. However, the research progress and trends in recent years on ARGs of aquatic environments are still unclear. This paper made a comprehensive understanding of the research advance, study trends and key topics of 1592 ARGs articles from 2012 to 2022 by bibliometrics. Publications on ARGs increased rapidly from 2012 to 2022, and scholars paid closer attention to the field of Environmental Sciences & Ecology. The most influential country and institution was mainly China and Chinese Academy of Sciences, respectively. The most articles (14.64 %) were published in the journal Science of the total environment. China and USA had the most cooperation, and USA was more inclined to international cooperation. PCR-based methods for water ARG research were the most widely used, followed by metagenomics. The most studied ARG types were sulfonamides, tetracyclines. Moreover, ARGs from wastewater and rivers were popularly concerned. Current topics mainly included pollution investigation, characteristics, transmission, reduction and risk identification of ARGs. Additionally, future research directions were proposed. Generally, by bibliometrics, this paper reviews the research hotspots and future directions of ARGs on a global scale, and summarizes the more important categories of ARGs, the pollution degree of ARGs in the relevant water environment and the research methods, which can provide a more comprehensive information for the future breakthrough of resistance mechanism, prevention and control standard formulation of ARGs.

Bibliometric and literature review of the development of mineral fertilizers

Mineral fertilizers are a new type of sustainable fertilizers, containing natural ores as the primary raw material with various nutrients and organic matters. This study combines two methods of bibliometric analysis to comprehensively review the progress of mineral fertilizers from 2000 to 2021. The results showed that the research on mineral fertilizers has increased in the past 21 years, especially after 2014. Developed countries studied mineral fertilizers more extensively than developing countries, but some developing countries, such as China and India, are also paying attention to this area in recent years. Chinese Academic of Sciences, Agriculture and Agri-Food Canada, and Chinese Academy of Agricultural Sciences were the main publishing institutions. Nutrient elements, changes in soil properties, and the effects on promoting crop growth were the main contents of the research. Still, such issues as bioremediation, soil environment improvement, and crop resistance are becoming hot spots. The field of mineral fertilizers showed a strong interdisciplinary nature and an increasingly comprehensive research perspective. The goal is that this synthesis will be used as a starting point for a broader study on responsible environmental management and research on improving fertilizer use efficiency.

A global bibliometric and visualized analysis of the status and trends of gastroparesis research

BACKGROUND

Gastroparesis has a substantial impact on the quality of life but has limited treatment options, which makes it a public health concern. No bibliometric studies on gastroparesis have been published thus far. Thus, this article aims to summarize and analyze research hotspots to provide a reference for clinical researchers.

MATERIALS AND METHODS

Gastroparesis-related research articles were searched in the Web of Science Core Collection (WOSCC), and relevant information was extracted after screening. A total of 1033 documents were analyzed with the bibliometric method using Microsoft Excel, Citespace, and VOSviewer.

RESULTS

Overall, our search retrieved 1033 papers contributed by 966 research institutions from 53 countries. Since 1980, publications in this field have increased rapidly. United States (n = 645) and Temple University (n = 122) were the most productive country and institution, respectively. Parkman, with 96 publications, was the most prominent author.

CONCLUSIONS

Research hotspots in gastroparesis can be summarized into four domains: innovation in diagnostic modalities, change of oral therapeutic agents, choice of surgical interventions, and pathological mechanisms. Future research on gastroparesis should focus on the quality of life of patients, diagnostic techniques, pyloromyotomy, and transpyloric stent placement.

Remote sensing for chromophoric dissolved organic matter (CDOM) monitoring research 2003-2022: A bibliometric analysis based on the web of science core database

Chromophoric dissolved organic matter (CDOM) occupies a critical part in biogeochemistry and energy flux of aquatic ecosystems. CDOM research spans in many fields, including chemistry, marine environment, biomass cycling, physics, hydrology, and climate change. In recent years, a series of remarkable research milestone have been achieved. On the basis of reviewing the research process of CDOM, combined with a bibliometric analysis, this study aims to provide a comprehensive review of the development and applications of remote sensing in monitoring CDOM from 2003 to 2022. The findings show that remote sensing data plays an important role in CDOM research as proven with the increasing number of publications since 2003, particularly in China and the United States. Primary research areas have gradually changed from studying absorption and fluorescence properties to optimization of remote sensing inversion models in recent years. Since the composition of oceanic and freshwater bodies differs significantly, it is important to choose the appropriate inversion method for different types of water body. At present, the monitoring of CDOM mainly relies on a single sensor, but the fusion of images from different sensors can be considered a major research direction due to the complex characteristics of CDOM. Therefore, in the future, the characteristics of CDOM will be studied in depth inn combination with multi-source data and other application models, where inversion algorithms will be optimized, inversion algorithms with low dependence on measured data will be developed, and a transportable inversion model will be built to break the regional limitations of the model and to promote the development of CDOM research in a deeper and more comprehensive direction.

Coronary slow flow research: a bibliometric analysis

BACKGROUND

Studies on coronary slow flow are receiving increasing attention, but objective evaluations are still lacking. The purpose of this study was to visualize the current status and research hotspots of coronary slow flow through bibliometric analysis.

METHODS

All relevant publications on coronary slow flow from 2003 to 2022 were extracted from the Web of Science Core Collection database and analyzed by VOSviewer and CiteSpace visualization software. Year of publication, journal, country/region, institution, and first author of each paper, as well as research hotspots were identified.

RESULTS

A total of 913 publications were retrieved. The journal with the most publications was Coronary Artery Disease. The country/region with the most publications was Turkey, followed by China and the United States. The institution with the largest publication volume was Turkey Specialized Higher Education Research Hospital. The author with the largest publication volume was Chun-Yan Ma from China. Keyword analysis indicated that "treatment and prognosis", "pathogenesis and risk factors" and "diagnosis" were the clustering centers of coronary slow flow, and the research hotspots gradually changed with time, from pathogenesis to treatment and prognosis.

CONCLUSION

Future research will focus on the search for effective and non-invasive detection indicators and treatments of coronary slow flow. Collaboration needs to be enhanced between different institutions or countries/regions, which would improve clinical outcomes for patients with coronary slow flow.

Pharmacovigilance for rare diseases: a bibliometrics and knowledge-map analysis based on web of science

OBJECTIVES

The aims of this paper is to search and explore publications in the field of pharmacovigilance for rare diseases and to visualize general information, research hotspots, frontiers and future trends in the field using the bibliometric tool CiteSpace to provide evidence-based evidence for scholars.

METHODS

We searched the Web of Science Core Collection (WoSCC) for studies related to pharmacovigilance for rare diseases, spanning January 1, 1997-October 25, 2022. CiteSpace software was utilized to discuss countries/regions, institutions, authors, journals, and keywords.

RESULTS

After screening, a total of 599 valid publications were included in this study, with a significant upward trend in the number of publications. These studies were from 68 countries/regions with the United States and the United Kingdom making the largest contributions to the field. 4,806 research scholars from 493 institutions conducted studies on pharmacovigilance for rare diseases. Harvard University and University of California were the top two productive institutions in the research field. He Dian of the Affiliated Hospital of Guizhou Medical University and Peter G.M. Mol of the University of Groningen, The Netherlands, were the two most prolific researchers. The Cochrane Database of Systematic Reviews and the New England Journal of Medicine were the journals with the highest number of articles and co-citation frequency respectively. Clinical trial, therapy and adverse event were the top three most cited keywords.

CONCLUSIONS

Based on keywords co-occurrence analysis, four research topics were identified: orphan drug clinical trials, postmarketing ADR surveillance for orphan drugs, rare diseases and orphan drug management, and diagnosis and treatment of rare diseases. Immune-related adverse reactions and benefit-risk assessment of enzyme replacement therapy were at the forefront of research in this field. Treatment outcomes, early diagnosis and natural history studies of rare diseases may become hotspots for future research.

Visualization analysis of research on pre-colonoscopy bowel preparation

BACKGROUND

Bowel preparation is an essential step before colonoscopy, and its research topics are relatively scattered. Understanding the research status and development trend of bowel preparation is of great value for disease research and actual clinical work. However, there is currently a lack of research in this field in the form of bibliometrics.

AIM

To understand the research hotspots and development trends of bowel preparation during colonoscopy around the world.

METHODS

The literature about the topics of bowel preparation was retrieved from the CNKI, Wanfang, VIP, China Biomedical Literature Database (CBM), and Web of Science core datasets from the inception of the database to September 10, 2022. CiteSpace 6.1. R3 was used to visually analyze the annual number of publications, countries, institutions, authors, keywords, clusters, and co-citation literature.

RESULTS

A total of 2340 Chinese and 2574 English publications were included, and the number of annual publications showed an increasing trend from year to year. The author with the largest number of publications worldwide was Hassan Cesare, and the most productive countries included USA, Korea, UK, Italy, and China. Meng Xiao-Fen, Zhang Yuan-Yuan, and Niu Mei-E were the China's most prolific authors. The First Affiliated Hospital of Suzhou University, the General Hospital of the Chinese People's Liberation Army, and the Second Affiliated Hospital of Xi'an University were the most prolific institutions. Research hotspots focused on the quality of bowel preparation, the design of bowel preparation programs, and special groups for bowel preparation.

CONCLUSION

Studies related to bowel preparation have certain foundations, and China's research can follow international hotspots, but cooperation among countries still needs to be strengthened. We should expand the research output related to bowel preparation based on a broader population and more suitable for the development of the era of big data, to provide higher quality research evidence for clinical practice.

Quantitative analysis of the current status and research trends of biochar research - A scientific bibliometric analysis based on global research achievements from 2003 to 2023

Biochar has excellent physical and chemical properties such as porosity, high carbon content, high cation exchange capacity, and rich surface functional groups and has been widely used in environmental remediation. Over the past 20 years, although various reviews have described the application of biochar as an environmentally friendly multifunctional material in environmental remediation, no comprehensive summary and analysis of the research trends in this field exists. To promote the rapid and stable development of the field of biochar, the current state of research on biochar is clarified using the bibliometric method in this report, and potential development directions and challenges for the future are identified. All relevant biochar literature from 2003-2023 was collected from the Chinese National Knowledge Infrastructure and Web of Science Core Collection. A total of 6,119 published Chinese papers and 25,174 English papers were selected for the quantitative analysis. CiteSpace, VOSviewer, and Scimago graphics software was used to summarize the numbers of papers published over the years, as well as the countries, institutions, and authors that published the most articles. Secondly, using keyword co-occurrence and emergence analysis, the recognized research hotspots in different areas such as adsorbents, soil remediation, catalytic oxidation, supercapacitors, and "biochar-microbial" synergy were analyzed. Finally, the prospects and challenges of biochar were assessed to provide new perspectives for further promoting its development in technological, economic, environmental, and other aspects.

Cooperation, hotspots and prospects for tourism environmental impact assessments

This study aims to identify hot spots, research limitations and future research directions in tourism environmental impact assessment (TEIA). We analyzed studies from the core database of Web of Science (WoS) based on their coauthorship, keyword co-occurrence and timeline with VOSviewer and CiteSpace. It was found that China, the United States, the United Kingdom, Australia and Spain are the major contributors to TEIA, and relatively stable cooperative groups have been formed among the authors. Research hotspots in the past 20 years mainly include: the impact of tourism activities in different tourist destinations on the environment, the approaches to assess the impact of tourism on the environment, and strategies on reducing the negative impact of tourism on the environment. We also found TEIA deficiency in the following five aspects: 1) insufficient studies on macro decision-making; 2) insufficient dynamic interaction analysis; 3) insufficient tourism heat footprint research; 4) insufficient studies on the positive effects of tourism on the environment; and 5) insufficient interdisciplinary innovation. Based on the findings, we suggest that 1) further studies be conducted on tourism activity type, time scale, macro pattern, environmental process and policy effect of tourism impact assessment with more variables and factors considered; 2) the impact of different types of tourism on each subsystem of the environment and the paths of the interaction among subsystems be explored from the perspective of system governance; 3) the study of thermal footprint generated by tourism activities be given more attention, especially large-scale tourism activities; 4) the positive impact of tourism activities on the ecological environment be studied, especially ecotourism; 5) the applicability of TEIA evaluation results be increased by means of interdisciplinary methods such as big data analysis.

Impact of antibiotics on microbial community in aquatic environment and biodegradation mechanism: a review and bibliometric analysis

Antibiotic residues in aquatic environments pose a potential hazard, and microbes, which play important roles in aquatic ecosystems, are vulnerable to the impacts of antibiotics. This study aimed to analyze the research progress, trends, and hot topics of the impact of antibiotics on microbial community and biodegradation mechanism using bibliometric analysis. An in-depth analysis of the publication characteristics of 6143 articles published between 1990 and 2021 revealed that the number of articles published increased exponentially. The research sites have been mainly concentrated in the Yamuna River, Pearl River, Lake Taihu, Lake Michigan, Danjiangkou Reservoir, etc., illustrating that research around the world is not even. Antibiotics could change the diversity, structure, and ecological functions of bacterial communities, stimulate a widespread abundance of antibiotic-resistant bacteria and antibiotic-resistant genes, and increase the diversity of eukaryotes, thus triggering the shift of food web structure to predatory and pathogenic. Latent Dirichlet allocation theme model analysis showed three clusters, and the research hotspots mainly included the effect of antibiotics on the denitrification process, microplastics combined with antibiotics, and methods for removing antibiotics. Furthermore, the mechanisms of microbe-mediated antibiotic degradation were unraveled, and importantly, we provided bottlenecks and future research perspectives on antibiotics and microbial diversity research.

Research landscape and hotspots of selective catalytic reduction (SCR) for NOx removal: insights from a comprehensive bibliometric analysis

Selective catalytic reduction (SCR) has been one of the most efficient and widely used technologies to remove nitrogen oxides (NO_x). SCR research has developed rapidly in recent years, which can be reflected by the dramatic increase of related academic publications. Herein, based on the 10,627 documents from 2001 to 2020 in Web of Science, the global research landscape and hotspots in SCR are investigated based on a comprehensive bibliometric analysis. The results show that SCR research has developed positively; the annul number of articles increase sharply from 246 in 2001 to 1092 in 2020. People's Republic of China and Chinese Academy of Sciences are the most productive country and institution, respectively. The global collaboration is extensive and frequent, while People's Republic of China and USA have the most frequent research cooperation. Applied Catalysis B-Environmental is the leading publication source with 711 records. Five major research areas on SCR are identified and elaborated, including catalyst, reductant, deactivation, mechanism, and others. Zeolite is the most widely studied SCR catalyst, while copper, silver, platinum, and iron are the most popular metal elements in catalyst. Ammonia (NH₃) is dominated among various SCR reductants, while hydrocarbon reductant has gained more attention. Sulfur dioxide (SO₂) and vapor are the two most concerned factors leading to catalyst deactivation, and catalyst regeneration is also an important research topic. Density functional theory (DFT), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and kinetics are the most widely used methods to conduct mechanism study. The studies on "low temperature," "atomic-scale insight," "elemental mercury," "situ DIRFTS investigation," "arsenic poisoning," "SPOA-34," "Cu-CHA catalyst," "TiO₂ catalyst," and "Ce catalyst" have been the hotspots in recent years.

Global trends in research on extracorporeal shock wave therapy (ESWT) from 2000 to 2021

BACKGROUND

This study intended to analyze the application of extracorporeal shock wave therapy in medicine and to evaluate the quality of related literature.

METHODS

All publications were extracted from 2000 to 2021 from the Web of Science Core Collection (WoSCC). The literature characteristics were depicted by VOSviewer (version 1.6.15) and the online bibliometric website ( http://bibliometric.com/ ). The future trends and hotspots were conducted by Bibliographic Item Co-occurrence Matrix Builder (version 2.0) and gCLUTO software.

RESULTS

We analyzed 1774 articles corresponding to the criteria for ESWT publications from 2000 to 2021. Most studies were conducted within the United States and China which besides have the most cooperation. The most published research institutions are Chang Gung University, Kaohsiung Chang Gung Memorial Hospital, and Kaohsiung Medical University. Six research hotspots were identified by keyword clustering analysis: Cluster0: The effects of ESWT on muscle spasticity; Cluster1: The application of ESWT in osteoarthritis (OA); Cluster2: Therapeutic effect of ESWT on tendon diseases; Cluster3: Early application of ESWT/ESWL in urolithiasis; Cluster4: The Role of angiogenesis in ESWT and the efficiency of ESWT for penile disease; Cluster5: The Special value of radial extracorporeal shock wave therapy (rESWT).

CONCLUSIONS

A comprehensive and systematic bibliometric analysis of ESWT was conducted in our study. We identified six ESWT-related research hotspots and predicted future research trends. With the gradual increase of research on ESWT, we find that ESWT is used more and more extensively, such in musculoskeletal disease, bone delay union, neurological injury, andrology disorders, lymphedema, and so on. In addition, the mechanism is not destructive damage, as initially thought, but a restorative treatment. Furthermore, delayed union, cellulite, burn, and diabetic foot ulcers may be the future direction of scientific study.

A bibliometric and visual analysis of contaminant transport modeling in the groundwater system: current trends, hotspots, and future directions

Contaminant transport modeling (CTM) in the groundwater represents the complex bio-geo-chemical processes in the subsurface system and plays a vital role in designing remediation strategies for contaminated sites. Hence, this study evaluated 1955 articles on CTM-based studies published from 2010 to 2022 by utilizing the Scopus® database to provide a quantitative analysis of current trends and future directions. A systematic approach comprised of a bibliometric survey and visualization of various networks was conducted with the VOSviewer and Biblioshiny software for quantitative analysis of progress of CTM research field over the past decade. The hotspots and evolution of themes of CTM were found using Sankey diagrams, and thematic maps. It was observed that articles were published at an exponential rate over past 5 years. The analysis of Scopus® database revealed that the average citations per article and the average citations per year per article were 14.7 and 2.225. In the past decade, USA published 489 articles and emerged as the leading country based on mutual collaborations and cooperation with other top 9 most productive countries. Flinders University was ranked in the first position based on the number of articles, followed by Pacific Northwest National Laboratory. The findings obtained from this study can help researchers identify exploitation and core areas, to understand better the direction of research of mathematical model development, and to determine hotspots of CTM research field.

Knowledge graph of wastewater-based epidemiology development: A data-driven analysis based on research topics and trends

Wastewater-based epidemiology (WBE) has contributed significantly to the monitoring of drug use and transmission of viruses that has been published in numerous research papers. In this paper, we used LitStraw, a self-developed text extraction tool, to extract, analyze, and construct knowledge graphs from nearly 900 related papers in PDF format collected in Web of Science from 2000 to 2021 to analyze the research hotspots and development trends of WBE. The results showed a growing number of WBE publications in multidisciplinary cross-collaboration, with more publications and close collaboration between the USA, Australia, China, and European countries. The keywords of illicit drugs and pharmaceuticals still maintain research hotness, but the specific research hotspots change significantly, among which the research hotspots of new psychoactive substances, biomarkers, and stability show an increasing trend. In addition, judging the spread of COVID-19 by the presence of SARS-CoV-2 RNA in sewage has become the focus since 2020. This work can show the development of WBE more clearly by constructing a knowledge graph and also provide new ideas for the paper mining analysis methods in different fields.

A bibliometric analysis of river health based on publications in the last three decades

Rivers are a vital part of the earth's environment and the basis for human survival. River health has been widely concerned by scholars and practitioners, and the number of studies in this area is increasing. In order to examine the evolution of river health research and identify the research frontiers, a total of 675 articles were retrieved from the Web of Science Core Collection database, and CiteSpace was used for bibliometrics. The results revealed that the research on river health is multidisciplinary. Freshwater Biology and Ecological Indicators were two of the most influential journals. Researchers and institutions from America, Australia, and China were the core research forces, and a certain gap was observed between developed and developing countries in river health. The most productive institution was Michigan State University, followed by Griffith University and Hohai University. There are three development trends in river health: (1) Research scale is expanding; (2) Research methods are diversified and interdisciplinary; and (3) Evaluation index is more comprehensive and systematic. The frontier of river health had been expanded from the connotation of river health to the evaluation methods, evaluation indexes, and comprehensive river ecological research. Overall, research on river health is a well-developed and promising research field. This study provides a framework in the river health field for new researchers and helps scholars to identify further potential perspectives on collaborators, research frontiers, hotspots, and research trends.

Insights into research on myocardial ischemia/reperfusion injury from 2012 to 2021: a bibliometric analysis

BACKGROUND

Numerous studies on myocardial ischemia/reperfusion (MI/R) injury have been undertaken in recent years. Hotspots and developmental trends in MI/R research are being rapidly updated. However, there has been no bibliometric analysis that systematically evaluates existing literature on MI/R injury. Our study explores developments in MI/R research over the past decade, and provides a reference for future research.

MATERIALS AND METHODS

Both experimental and clinical publications on MI/R injury from 2012 to 2021 were retrieved from the Web of Science Core Collection database. The CiteSpace and VOSviewer tools were used to perform a bibliometric analysis.

RESULTS

A total of 8419 papers were analyzed. The number of annual publications demonstrated an overall upward trend, rising from 629 publications in 2012 to 1024 publications in 2021. China, the USA, Germany, England, and Italy were the top five contributors to MI/R studies. The Fourth Military Medical University in China contributed the most publications (188, 2.23%), while the University College London in England cooperated the most with relevant research institutions. Derek J Hausenloy (University College London), Derek M Yellon (University College London), and Gerd Heusch (University of Essen Medical School) were the top three most active and influential scholars according to the H-index. Among the top 10 journals with the most publications, Basic Research in Cardiology had the highest impact factors. The top three co-cited journals were Circulation, Circulation Research, and Cardiovascular Research. According to a co-cited reference analysis, MI/R research can be divided across 10 major subfields of mitophagy, cardioprotection, inflammation, remote ischemic preconditioning, long non-coding RNA, melatonin, postconditioning, mitochondria, microvascular obstruction, and ferroptosis. After 2018, the keywords with strongest citation bursts included extracellular vesicles, long non-coding RNA, cell proliferation, microRNA, mitochondrial quality control, mitophagy, biomarker, and mitochondrial biogenesis.

CONCLUSIONS

The present study reveals the influential authors, cooperating institutions, and main research foci in the field of MI/R injury in the past decade. The latest hotspots are a more in-depth insight into the molecular mechanisms underlying MI/R injury, such as mitochondrial quality control, non-coding RNAs, cell proliferation, and extracellular vesicles.

Bibliometric analysis of IgG4-related disease research from 2003 to 2022 based on Web of Science Core Collection Databases

This study aimed to perform a bibliometric analysis of the IgG4-related disease (IgG4-RD) research field over the past 20 years to explore its research hotspots and trends. The literature of IgG4-RD published in the Web of Science Core Collection databases was reviewed from January 1, 2003, to April 30, 2022. A bibliometric analysis was carried out using CiteSpace software to evaluate and visualize the evolving dynamics and hotspots in the field of IgG4-RD. A total of 3174 IgG4-RD articles were reviewed. Since 2011, there has been a rapid increase in published literature. Japan is the highest yielding country and Kanazawa University the highest yielding institution. The USA has the highest centrality (0.34) and plays a critical role in cooperation and communication of IgG4-RD research. Nine highly connected clusters of IgG4-RD were observed by keyword analysis. Research hotspots included IgG4-RD involved organs and differentiation from Rosai-Dorfman disease and primary sclerosing cholangitis. Further research topics include pathogenesis, relapse, and malignancy. As a cross-discipline systemic disease, IgG4-RD requires attention by clinicians in multiple fields. This bibliometric analysis can help researchers grasp trends and provide new perspectives for future research on IgG4-RD.

Visual analysis and evaluation of clinical research on Traditional Chinese medicine compounds in treating insomnia of Yin deficiency syndrome

ETHNOPHARMACOLOGICAL RELEVANCE

Insomnia is a common form of sleep disorder. Traditional Chinese medicine (TCM) compounds have definite curative effects and a low incidence of adverse reactions, which is recognized to be an effective intervention means for the treatment of insomnia.

AIM OF THE STUDY

Based on mining the clinical research data of treating insomnia of yin deficiency syndrome (IYDS) with TCM compounds systematically, the study is to analyze the research hotspots and development trends in this field, explore the medication rule, evaluate the quality of research, so as to provide reference and direction for clinical application and scientific research in this field.

MATERIALS AND METHODS

The relevant literature was retrieved and managed by evidence-based medicine strategy and EndNote software respectively. The bibliometric method was used to mine and analyze data characteristics. The VOSviewer software was used to make visual knowledge maps, the IBM SPSS Modeler software was used for association rule analysis of herbs, and the Cochrane tool and MINORS scale were used for quality analysis of literature.

RESULTS

(1) A total of 184 related studies were included according to the inclusion and exclusion criteria. (2) The research popularity showed a dynamic upward trend and the research hotspot showed a trend of migration and refinement, etc. (3) The commonly used herbs in this field were Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F.Chow, etc; the commonly used TCM prescriptions were Huanglian Ejiao Decoction, etc; the commonly used dosage forms were traditional decoction, etc; the commonly used combinations of herbs included Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F.Chow-Poria cocos（Schw.）Wolf, etc. (4) The rate of the studies containing ethical review numbers and clear inclusion standards did not reach 50%, and the risk bias of methodological was high. However, a separate analysis of data showed that the specification of study design was on the rise obviously in recent years, and Meta-analysis and sensitivity analysis could confirm the effectiveness and stability of clinical efficacy which was the key indicator in treating IYDS with TCM prescriptions. There were significant differences among administration protocols of different clinical studies of the same name TCM compounds. However, the scientific significance of each unique dosing regimen were expected to be elaborated or discussed.

CONCLUSION

The clinical research number of TCM compounds treating IYDS was in a dynamic upward trend, and the outcome indicators tended to be diversified and detailed. The dosage forms mainly included decoction, supplemented by Chinese patent medicine. The design of clinical studies in this field was not standardized enough, but the key indicators were scientific and stable. We expected that later studies could pay more attention to improving the standardization of trial design, reducing the risk bias in the process of methodological design, conducting high-quality standardized multicenter, large-sample randomized controlled clinical trials to provide scientific evidence with high evidentiary strength, establishing the recognized administration protocols for the same name TCM prescriptions or clarifying the targeting of different protocols, and promoting the application and popularity of TCM compounds in treating IYDS.

Mapping the global research landscape on insulin resistance: Visualization and bibliometric analysis

BACKGROUND

Insulin resistance is a risk factor for metabolic syndromes and is associated with a wide variety of metabolic illnesses, including obesity, type 2 diabetes, and cardiovascular disease.

AIM

To investigate and map global insulin resistance studies.

METHODS

A bibliometric methodology was applied to the literature retrieved from the Scopus database and Reference Citation Analysis (https://www.referencecitationanalysis.com) by using a validated search strategy. The study period was limited from 2002 to 2021. Bibliometric indicators and mapping were presented.

RESULTS

A total of 26808 articles on the topic of insulin resistance were included in the Scopus database. The articles included research articles (n = 21918; 81.76%), review articles (n = 2641; 9.85%), and letters (n = 653; 2.44%). During the study period, 136 countries contributed to the research on insulin resistance. The highest number of articles was from the United States (n = 7360; 27.45%), followed by China (n = 3713; 13.85%), Japan (n = 1730, 6.45%), Italy (n = 1545; 5.54%), and the United Kingdom (n = 1484; 5.54%). The retrieved articles identified two main research themes: “inflammatory mechanisms in the regulation of insulin resistance” and “mechanisms linking obesity to insulin resistance”.

CONCLUSION

Our data show that insulin resistance has steadily gained interest from researchers, as evidenced by the number of citations and yearly publications. Publications have grown significantly in the last decade, while low-income countries with greater burdens continue to produce fewer publications in this field. This approach might assist researchers in choosing new research areas and recognizing research hotspots and frontiers. In the future, perhaps high-quality clinical evidence will be acquired.

Research trends and hotspots of aquatic biofilms in freshwater environment during the last three decades: a critical review and bibliometric analysis

Freshwater periphytic biofilms (FPBs), existing widely in various aquatic environments, have attracted extensive attention for many years. In the present study, a bibliometric analysis based on Web of Science Core Collection (WoSCC) was used to understand the research progress, trends, and hot topics of FPBs qualitatively and quantitatively. The results indicated that publications on FPBs have increased from 1991 to 2020 rapidly, and researchers have focused more on the areas of environmental sciences, microbiology, and marine freshwater biology. The most influential countries were mainly the USA, Spain, France, and Germany. Cooperation network analysis reflected that the USA and its affiliated institutions played crucial roles in the research of FPB cooperation, but the collaboration between core author groups still fell short. Based on the analysis of top 20 high-cited FPB documents over the last 30 years, research hotspots mainly included micro-observation and assembly mechanisms of FPBs; interactions of FPBs and pollutants including heavy metals, antibiotic resistance genes, pathogens, organic pollutants, and nanoparticles; and the role of FPBs for biogeochemical cycling, especially nitrogen cycling. Additionally, future research directions were proposed. Overall, this study provides a comprehensive and systematic overview of FPBs, which is useful for research development and researchers who are interested in this area.

A 20-year bibliometric analysis of Fuchs endothelial corneal dystrophy: from 2001 to 2020

PURPOSE

The aim of this study was to identify trends and focuses in the field of Fuchs endothelial corneal dystrophy (FECD) research.

METHODS

A bibliometric analysis based on the Web of Science Core Collection was conducted. All publications related to FECD from 2001 to 2020 were extracted and analyzed. VOSviewer v.1.6.17 was used to construct a visualization map and evaluate the trends and focuses in FECD research.

RESULTS

A total of 1,041 publications were extracted. The rate of global publications has steadily increased. The United States produced the highest number of publications (461), the highest number of citations (18,757), and the highest H index (69). Melles GRJ published the highest number of papers (60), and Price FW had the highest number of citations (4,154) in the FECD research field. The highest number of publications came from the journal Cornea (279). Keywords were classified into four clusters: (1) corneal transplantation surgery, (2) surgical techniques and instruments, (3) corneal parameter measurement, and (4) genetic and molecular pathomechanisms. The average appearing years (AAYs) of the keywords were evaluated. Recently appearing keywords included "Tcf4 gene" (AAY of 2018.3), "ctg18.1" (AAY of 2017.2), "trinucleotide repeat expansion" (AAY of 2018.3), "rock inhibitor" (AAY of 2017.4), and "descemetorhexis" (AAY of 2017.4).

CONCLUSIONS

The United States has a dominant position in FECD research. Although corneal transplantation surgery has been the most mainstream area of FECD research field for a long time, gene mutations such as the TCF4 CTG trinucleotide repeat expansion, nonsurgical interventions such as rho-associated kinase inhibitors, and newer surgical methods such as descemetorhexis without endothelial keratoplasty are potential research hotspots.

Ecohydrology 2.0

This paper aims at a definition of the domain of ecohydrology, a relatively new discipline borne out of an intrusion-as advertised by this Topical Collection of the Rendiconti Lincei-of hydrology and geomorphology into ecology (or vice-versa, depending on the reader's background). The study of hydrologic controls on the biota proves, in our view, significantly broader than envisioned by its original focus that was centered on the critical zone where much of the action of soil, climate and vegetation interactions takes place. In this review of related topics and contributions, we propose a reasoned broadening of perspective, in particular by firmly centering ecohydrology on the fluvial catchment as its fundamental control volume. A substantial unity of materials and methods suggests that our advocacy may be considered legitimate.

A comprehensive review of the circulation of microplastics in aquatic ecosystem using scientometric method

Nowadays, the extensive application of microplastics (MPs) has led to the gradual accumulation of toxicity in aquatic environment and caused potential harm to aquatic organisms and human life, which has become a hot issue of worldwide concern. Although MPs show inert or sublethal toxicity in many cases, its long-term existence can still cause harmful ecological effects. However, to our knowledge, there is a lack of comprehensive literature on the current research hotspots, circulation process, and future development trend of MPs in aquatic ecosystem. This study aims to comprehend the current research hotspots and future development trend in the field of the MPs in aquatic ecosystem using scientometric method. And the circulation process of MPs in aquatic ecosystem is also investigated. The results indicate the most of the current publications on MPs in aquatic ecosystems focus on the formation and harmful properties of MPs. The current research hotspots mainly include the causes of the formation of MPs, the extent of contamination, deposition phenomena, and the toxicity and harm caused to aquatic organisms and humans after ingestion. And the future trends in the researches related to MPs mainly include the study of microplastic cycling processes in aquatic and terrestrial ecosystems, as well as the effective collection of microplastics and their conversion into valuable carbon sources. This review has filled in the knowledge gap in the field of MPs research in aquatic ecosystem to some extent and plays a guiding role in the future researches.

A bibliometric analysis of mountain ecosystem services, 2000-2019

Research on mountain ecosystem services (MES) under the influence of climate change and human activities has gradually become the focus of academic attention in recent years. Here, this study analyzes the research hotspots and frontiers of this field based on metrics including main research forces, core journals and papers, research hotspots and topics by using the methods of bibliometrics and text mining. The results revealed the following: (1) the number of papers is increasing rapidly in recent years. From 2015 to 2019, 929 papers were published, with an average of 185 papers per year. But the average cited times of those papers is declining, dropped from 6.01 in 2016 to 4.2 in 2019. The USA, UK, and China rank the top three of the number of papers. Univ Maryland, Univ Oxford and Univ Wisconsin have the greatest influence, with an average of more than 77 citations per paper; (2) The most cited journals are PNAS, WETLANDS, ECOLOGY, AND SOCIETY, which are cited 191.54, 53.91, and 40.00 respectively. Most papers were published in OA journals including SUSTAINABILITY, WATER, Forests since 2017. Ten core papers undertaking knowledge transfer in this field have been identified; (3) analysis of the keywords found a new trend of integration of natural science and humanities. In two development stages of 2000-2014 and 2015-2019, the research hotspots mainly focused on mountain water resources, forest resources, land resources and the impact of climate change and human activities, and there are obvious differences and characteristics in different stages. The hotspot worthy of attention in the near future is the assessment of mountain ecosystem services capacity and value. This is the first comprehensive visualization and analysis of the research hotspots and trends of mountain ecosystem services.

Global research trends in cardiac arrest research: a visual analysis of the literature based on CiteSpace

BACKGROUND

The high morbidity, high mortality and low survival rate of cardiac arrest (CA) cause a heavy global burden. We aimed to analyze the changes in scientific output related to CA over the past two decades.

METHODS

We analyzed the scientific output related to CA from 2000 to 2020 via the Web of Science. The data were analyzed using CiteSpace software.

RESULTS

In total, 28,312 articles relating to CA were identified in the Web of Science. The volume of scientific research output in the field of global CA research was mainly distributed in the Americas, Europe and Asia, covering a wide range. Of the 28,312 articles, the research content of the highly cited literature mainly focused on CA, mild hypothermia treatment, and prognosis of CA patients.

CONCLUSION

Various scientific methods were applied to reveal scientific productivity, collaboration, and research hotspots in the CA research field. Cardiopulmonary resuscitation (CPR), extracorporeal membrane oxygenation (ECMO), survival and target temperature management are research hotspots. Future research on CA will continue to focus on its treatment and prognosis to improve the survival rate of CA patients.

How do urban rainfall-runoff pollution control technologies develop in China? A systematic review based on bibliometric analysis and literature summary

Rapid urbanization in China is driving the need of urban rainfall-runoff pollution control technologies due to adverse impacts on water environment. In this study, literature from China National Knowledge Infrastructure, Web of Science and Scopus in 1995/1/1-2019/5/15 are used to review research hotspots, development process and future directions of urban rainfall-runoff pollution control technologies in China and global world. Temporal evolution of publications showed that source reduction played better growing trend in urban rainfall-runoff pollution control field for both China and global world. Furthermore, with bibliometric tool, density visualization maps and co-occurrence network maps were created to identify research hotspots in China and global world. By comprehensively analyzing research hotspots above and development process from extracted literature, future directions of urban rainfall-runoff pollution control technologies were predicted. For model and strategy, both China and global world would concern on the accuracy of models to evaluate combination technologies. For source reduction, China would explore rainwater purification in sponge city, while global world would investigate match characteristics between specific regions and control technologies, combination between model and technologies, and improvement of pollutants removal. For process control, China would enhance ecological gutter inlet performance, whereas global world would concentrate on optimization of rainwater harvesting system. For post treatment, China would estimate modified hydrocylone and coagulation technology, and improve performance of filtration systems, riparian buffers and constructed wetlands, while global world would explore ecological and landscape function of constructed wetlands. Since China ranked first in producing Western publications and was the second most cited country for Western publications recently, China would significantly influence future development of urban rainfall-runoff pollution control technologies around the world. Meanwhile, some directions including infiltration basin and rainwater harvesting system were still shortcomings for China due to a late start of urban rainfall-runoff pollution control technologies in China.

Global Research Trends in Robotic Applications in Spinal Medicine: A Systematic Bibliometric Analysis

OBJECTIVE

We systematically evaluated the global research trends in robotic application on the spine through bibliometric analysis and mapping knowledge domains.

METHODS

A systematic literature search was performed of the PubMed and Web of Science, including the Science Citation Index Expanded, databases. The number, countries, journals, and authors of the publications, total citations, average publication year, and institution sources were analyzed using Microsoft Excel, the Online Analysis Platform of Bibliometrics, and VOSviewer. The hotspots were analyzed and visualized using VOSviewer.

RESULTS

We identified a total of 2135 publications. The United States ranked first in the number of publications (n = 824; 38.63%) and frequency of citations (n = 29,075). Northwestern University had the highest number of publications (n = 67) and Harvard University the highest number of citations (n = 4198). The Journal of NeuroEngineering and Rehabilitation published the largest number of reports (n = 73), and the most frequently cited journal was Nature (n = 3844 citations). The research hotspots were divided into 3 categories analyzed by VOSviewer: rehabilitation, basic science, and surgery. According to the average publication year, the most recent hotspot was radiation exposure, and the earliest hotspot was radiosurgery.

CONCLUSIONS

The number of studies of robotic application on the spine has continued to increase. The United States was the greatest contributor to robotic applications on the spine. Robot-assisted rehabilitation for neurological and orthopedic lesions is still a major research hotspot. The range of robotic applications on the spine has expanded from assisted rehabilitation to assisted rehabilitation and surgery.

Mapping the knowledge domain of the evolution of emergy theory: a bibliometric approach

Bibliometric and visualization tools are effective for uncovering information contained in vast amounts of literature data. We retrieved publications from the Web of Science (2008-2020) and used the Statistical Analysis Toolkit for Informetrics (SATI) and CiteSpace to conduct a bibliometric analysis of emergy studies, review the focus of the studies, summarize current research, and identify academic trends. The SATI-based charts provided an overall description of yearly published articles, literature sources, high-frequency keywords, authors, institutions, and highly cited papers. CiteSpace was applied to determine the frontiers and hotspots of emergy theory. A dual-map analysis was used to reveal the connection between multiple disciplines. Keyword clustering analysis was performed to evaluate research hotspots. Moreover, burst analysis and timeline maps presented a holistic picture of cutting-edge issues and the evolutionary trajectory of emergy studies in recent years. An alluvial flow map analysis of the landmark literature depicted the transmission of knowledge in the emergy field. In addition, this article also evaluated the current status of collaborative research in emergy-related fields. The results can provide a reference for researchers to explore hot issues or target a specific field of study.

Medical professionalism research characteristics and hotspots: a 10-year bibliometric analysis of publications from 2010 to 2019

An abundance of publications on medical professionalism have been published in recent years. Our study aimed to analyze the external characteristics of publications on professionalism using bibliometrics, to describe its current developments and trends, and to explore professionalism research hotspots using co-word analysis. We retrieved literature on professionalism published from 2010 to 2019 from the Web of Science database. Histcite and CiteSpace were used to analyze external characteristics of publications, including publication trends and distributions of publications by country/region, institution, author, and journal. Co-word analysis was conducted to analyze research hotspots, using the Bibliographic Item Co-Occurrence Matrix Builder and Graphical Clustering Toolkit. We constructed a strategic diagram to show the state of each research hotspot and the relationship between the various hotspots in this field. Results showed publications on professionalism increased in number year by year as a whole. The USA, including its institutions and authors, maintained the top position worldwide in terms of numbers of publications and citations. Among scholarly journals, Academic Medicine has published more articles and has had higher citations per paper than any other journal. Six research hotspots on professionalism were identified, visualized, and expounded. Of these, the theme of "measurement and evaluation of clinical competence" received the most attention in the field of professionalism. The reporting of quantifiable knowledge on the characteristics and research hotspots of publications could help inform gaps in the field of medical professionalism and provide evidence and guidance for future work for researchers, physicians, and educators.

Human gene therapy: A scientometric analysis

To provide a clear landscape, trends, and research frontiers of gene therapy, we systematically retrieved a total of 62,961 peer-viewed studies published between 1996 and 2020 from the Scopus, Web of Science, and 42,120 Inpadoc patent families from Derwent Innovation databases. Multiple bibliometric approaches suggest that gene therapy began to recover in 2013 after a period of significant decline. However, metrics in terms of authors and scholarly output growth, FWCI, annual citations, percentage of high-impact journal literature, and patent-citations per scholarly output are still weak at this stage, indicating a lack of research momentum. We also visualized gene therapy's knowledge structure by employing citation analysis, co-citation analysis, and co-word analysis, revealing its research hotspots and trends by text mining with Natural Language Processing. For the current predicament, we propose that the future success of gene therapy may depend on breakthroughs in more advanced and exhilarating technologies such as the CRISPR-Cas system, CAR-T cell therapies, and gene delivery vector technology. The results show that evidence-based bibliometrics allows the dissection of gene therapy to inform scientific planning and decision-making.

A bibliometric analysis of comparative research on the evolution of international and Chinese green supply chain research hotspots and frontiers

Green supply chain (GSC), one of the most vital sub-topics of sustainable development, indicates people provoking on the rationality of business practices and resource consumption patterns. Under the background of economy globalization, developing countries, especially China, severely affected by green barriers became the global focus. A systematic review of articles about GSC which published in leading journals of Web of Science Core Collection (WoSCC) and China Knowledge Resource Infrastructure (CNKI) is proposed for exploring publishing trends, the distribution of authors and journals, research topics, and hotspots and predicting frontiers by utilizing VOSviewer, Sci2, and CiteSpace. The results show that (1) there are differences in the attention of GSC between international and Chinese academia. (2) "Green" is referred to environmental friendly practices in international academia. Scholars advocate to promote management to strengthen cooperation among GSC members and boost technology investment to improve the comprehensive performance; however, specific practices such as "low-carbon," "emission reduction," "recycling," and "remanufacture" are referred to environmental friendly behaviors in Chinese academia. Scholars expect to avoid enterprises' short-term profit compression relying on government subsidies and make contracts to share environment protection cost equally out for ensuring GSC stable operation. (3) Exploring collaboration among GSC members using complex operation research and artificial intelligence will be international research frontier. Relevant papers are to provide Chinese research with merely innovation in methodology. Besides, the "government-enterprise-university-research institute-customer-economy" management mode proposed by development countries like China will enrich the international GSC research scope, leading international GSC knowledge structure to change. The contribution of this study is to afford reference for future research on GSC.

Bibliometrics and visualization analysis regarding research on the development of microplastics

Microplastics have caused considerable harm to the environment and threatened human health due to their strong adsorption and hard biodegradation. Therefore, the research of microplastic received increasing attention recently, producing numbers of related achievements. To comprehensively grasp the quantitative information of published papers on "microplastics," we analyzed the research progress and hotspots of "microplastics" through visualization software "VOSviewer." The results show that the number of literature on microplastics published from 2009 to 2019 increased exponentially (R2 = 0.9873). The top 10 cited references are mainly in "zooplankton ingesting microplastics," "microplastics in artificially cultivated bivalve," "microplastics in surface waters such as lakes," etc. The cutting-edge microplastics research is adsorption, biodegradation, ingestion and accumulation model, and toxicity analysis. In addition, the results predict that the combination of constructed wetland, biotechnology, and photocatalysis to remove microplastics will become new hotspots. The study provides researchers in microplastics with an overview of existing research and directional guidance for future research.

Global characteristics and trends of research on industrial structure and carbon emissions: a bibliometric analysis

The relationship between industrial structure and carbon emissions has been widely identified as a critical research topic by international organizations and academics. Using bibliometrics analysis, this study aimed at dissecting the global characteristics and trends of research on industrial structure and carbon emissions. Based on the 806 documents from 2004 to 2019 in Web of Science, this work was implemented from four aspects, including basic characteristics analysis, country/territory and institution analysis, category and journal analysis, and reference and keyword analysis. The results of this study showed rapid growth trends of research on industrial structure and carbon emissions from 2015 to 2019. The collaborations among countries and institutions were extensive worldwide with China, the USA, and the UK as the main participants. Furthermore, the corresponding research topics, research priorities, and research paths were summarized according to the references co-citation analysis and keywords cluster analysis, which from the perspective of the correlation between different types of industry with carbon emissions. Finally, the timezone view of the top 100 keywords indicated that the emerging trends in the research on industrial structure and carbon emissions were regional analysis, industrialization, and environmental efficiency, and prediction of carbon emissions peak and the spatial distribution in different types of industries were the hotspots in recent years. The findings provide a better understanding of global characteristics and trends that have emerged in this field, which can also offer reference for future research.

Review of global sanitation development

The implementation of the United Nations (UN) Millennium Development Goals (MDGs) and Sustainable Development Goals (SDGs) has resulted in an increased focus on developing innovative, sustainable sanitation techniques to address the demand for adequate and equitable sanitation in low-income areas. We examined the background, current situation, challenges, and perspectives of global sanitation. We used bibliometric analysis and word cluster analysis to evaluate sanitation research from 1992 to 2016 based on the Science Citation Index EXPANDED (SCI-EXPANDED) and Social Sciences Citation Index (SSCI) databases. Our results show that sanitation is a comprehensive field connected with multiple categories, and the increasing number of publications reflects a strong interest in this research area. Most of the research took place in developed countries, especially the USA, although sanitation problems are more serious in developing countries. Innovations in sanitation techniques may keep susceptible populations from contracting diseases caused by various kinds of contaminants and microorganisms. Hence, the hygienization of human excreta, resource recovery, and removal of micro-pollutants from excreta can serve as effective sustainable solutions. Commercialized technologies, like composting, anaerobic digestion, and storage, are reliable but still face challenges in addressing the links between the political, social, institutional, cultural, and educational aspects of sanitation. Innovative technologies, such as Microbial Fuel Cells (MFCs), Microbial Electrolysis Cells (MECs), and struvite precipitation, are at the TRL (Technology readiness levels) 8 level, meaning that they qualify as "actual systems completed and qualified through test and demonstration." Solutions that take into consideration economic feasibility and all the different aspects of sanitation are required. There is an urgent demand for holistic solutions considering government support, social acceptability, as well as technological reliability that can be effectively adapted to local conditions.

A scientometric review of emerging trends and new developments in agricultural ecological compensation

Agricultural ecological compensation has drawn an increasingly broad range of interest since early 1990s. In recent years, the volume of the literature grows rapidly. As a result, a systematic review of the diverse research field and its current trends becomes essential. This paper surveys the literature of agricultural ecological compensation between 1990 and 2016. Specifically, by employing CiteSpace information visualization software, we firstly identified the research hotspots and evolution path and then illustrated the frontier and developing trend of the domain in core and broader perspectives. It is found that the focus of the academic community has always been researches on the theoretical policy and application of the payment for agro-ecosystem services, agricultural ecological compensation based on contingent valuation method, and ecological compensation of farmland landscape and organic food production as well as willingness to accept/pay for land use and ecological protection. Meanwhile, we also found that, in recent years, qualitative research has received more and more attention in the field of agricultural ecological compensation, since global warming, agricultural carbon emissions, and other emerging environmental issues have aroused widespread concern of the people around the world. Moreover, we believed that more and more scholars will employ case study methodology to analyze agricultural ecological compensation in specific systems, regions, or circumstances in the future.

Past, current, and future research on microalga-derived biodiesel: a critical review and bibliometric analysis

Microalga-derived biodiesel plays a crucial role in the sustainable development of biodiesel in recent years. Literature related to microalga-derived biodiesel had an increasing trend with the expanding research outputs. Based on the Science Citation Index Expanded (SCI-Expanded) of the Web of Science, a bibliometric analysis was conducted to characterize the body of knowledge on microalga-derived biodiesel between 1993 and 2016. From the 30 most frequently used author keywords, the following research hotspots are extracted: lipid preparation from different microalga species, microalga-derived lipid and environmental applications, lipid-producing microalgae cultivation, microalgae growth reactor, and microalga harvest and lipid extraction. Other keywords, i.e., microalga mixotrophic cultivation, symbiotic system between microalga and other oleaginous yeast, microalga genetic engineering, and other applications of lipid-producing microalga are future focal points of research. Graphical abstract.

A bibliometric review of nitrogen research in eutrophic lakes and reservoirs

The global application of nitrogen is far greater than phosphorus, and it is widely involved in the eutrophication of lakes and reservoirs. We used a bibliometric method to quantitatively and qualitatively evaluate nitrogen research in eutrophic lakes and reservoirs to reveal research developments, current research hotspots, and emerging trends in this area. A total of 2695 articles in the past 25years from the online database of the Scientific Citation Index Expended (SCI-Expanded) were analyzed. Articles in this area increased exponentially from 1991 to 2015. Although the USA was the most productive country over the past 25years, China achieved the top position in terms of yearly publications after 2010. The most active keywords related to nitrogen in the past 25years included phosphorus, nutrients, sediment, chlorophyll-a, carbon, phytoplankton, cyanobacteria, water quality, modeling, and stable isotopes, based on analysis within 5-year intervals from 1991 to 2015 as well as the entire past 25years. In addition, researchers have drawn increasing attention to denitrification, climate change, and internal loading. Future trends in this area should focus on: (1) nutrient amounts, ratios, and major nitrogen sources leading to eutrophication; (2) nitrogen transformation and the bioavailability of different nitrogen forms; (3) nitrogen budget, mass balance model, control, and management; (4) ecosystem responses to nitrogen enrichment and reduction, as well as the relationships between these responses; and (5) interactions between nitrogen and other stressors (e.g., light intensity, carbon, phosphorus, toxic contaminants, climate change, and hydrological variations) in terms of eutrophication.