44 research outputs found
Yellow fever disease : density equalizing mapping and gender analysis of international research output
Background: A number of scientific papers on yellow fever have been published but no broad scientometric analysis on the published research of yellow fever has been reported. The aim of the article based study was to provide an in-depth evaluation of the yellow fever field using large-scale data analysis and employment of bibliometric indicators of production and quantity.
Methods: Data were retrieved from the Web of Science database (WoS) and analyzed as part of the NewQis platform. Then data were extracted from each file, transferred to databases and visualized as diagrams. Partially by means of density-equalizing mapping makes the findings clear and emphasizes the output of the analysis.
Results: In the study period from 1900 to 2012 a total of 5,053 yellow fever-associated items were published by 79 countries. The United States (USA) having the highest publication rate at 42% (n = 751) followed by far from Brazil (n = 203), France (n = 149) and the United Kingdom (n = 113). The most productive journals are the "Public Health Reports", the "American Journal of Tropical Medicine and Hygiene" and the "Journal of Virology". The gender analysis showed an overall steady increase of female authorship from 1950 to 2011. Brazil is the only country of the five most productive countries with a higher proportion of female scientists.
Conclusions: The present data shows an increase in research productivity over the entire study period, in particular an increase of female scientists. Brazil shows a majority of female authors, a fact that is confirmed by other studies
A Novel Radiomics-Based Tumor Volume Segmentation Algorithm for Lung Tumors in FDG-PET/CT after 3D Motion Correction-A Technical Feasibility and Stability Study
Positron emission tomography (PET) provides important additional information when applied in radiation therapy treatment planning. However, the optimal way to define tumors in PET images is still undetermined. As radiomics features are gaining more and more importance in PET image interpretation as well, we aimed to use textural features for an optimal differentiation between tumoral tissue and surrounding tissue to segment-target lesions based on three textural parameters found to be suitable in previous analysis (Kurtosis, Local Entropy and Long Zone Emphasis). Intended for use in radiation therapy planning, this algorithm was combined with a previously described motion-correction algorithm and validated in phantom data. In addition, feasibility was shown in five patients. The algorithms provided sufficient results for phantom and patient data. The stability of the results was analyzed in 20 consecutive measurements of phantom data. Results for textural feature-based algorithms were slightly worse than those of the threshold-based reference algorithm (mean standard deviation 1.2%-compared to 4.2% to 8.6%) However, the Entropy-based algorithm came the closest to the real volume of the phantom sphere of 6 ccm with a mean measured volume of 26.5 ccm. The threshold-based algorithm found a mean volume of 25.0 ccm. In conclusion, we showed a novel, radiomics-based tumor segmentation algorithm in FDG-PET with promising results in phantom studies concerning recovered lesion volume and reasonable results in stability in consecutive measurements. Segmentation based on Entropy was the most precise in comparison with sphere volume but showed the worst stability in consecutive measurements. Despite these promising results, further studies with larger patient cohorts and histopathological standards need to be performed for further validation of the presented algorithms and their applicability in clinical routines. In addition, their application in other tumor entities needs to be studied
Telemedicine - a scientometric and density equalizing analysis
Background As a result of the various telemedicine projects in the past years
a large number of studies were recently published in this field. However, a
precise bibliometric analysis of telemedicine publications does not exist so
far. Methods The present study was conducted to establish a data base of the
existing approaches. Density-equalizing algorithms were used and data was
retrieved from the Thomson Reuters database Web of Science. Results During the
period from 1900 to 2006 a number of 3290 filed items were connected to
telemedicine, with the first being published in 1964. The studies originate
from 101 countries, with the USA, Great Britain and Canada being the most
productive suppliers participating in 56.08 % of all published items.
Analyzing the average citation per item for countries with more than 10
publications, Ireland ranked first (10.19/item), New Zealand ranked second
(9.5/item) followed by Finland (9.04/item). The citation rate can be assumed
as an indicator for research quality. The ten most productive journals include
three journals with the main focus telemedicine and another five with the main
focus “Information/Informatics”. In all subject categories examined for
published items related to telemedicine, “Health Care Sciences & Services”
ranked first by far. More than 36 % of all publications are assigned to this
category, followed by “Medical Informatics” with 9.72 % and “Medicine, General
& Internal” with 8.84 % of all publications. Conclusion In summary it can be
concluded that the data shows clearly a strong increase in research
productivity. Using science citation analysis it can be assumed that there is
a large rise in the interest in telemedicine studies
A Density-Equalizing Mapping Analysis of the Global Research Architecture
Methicillin-resistant Staphylococcus aureus (MRSA) has evolved as an alarming
public health thread due to its global spread as hospital and community
pathogen. Despite this role, a scientometric analysis has not been performed
yet. Therefore, the NewQIS platform was used to conduct a combined density-
equalizing mapping and scientometric study. As database, the Web of Science
was used, and all entries between 1961 and 2007 were analyzed. In total, 7671
entries were identified. Density equalizing mapping demonstrated a distortion
of the world map for the benefit of the USA as leading country with a total
output of 2374 publications, followed by the UK (1030) and Japan (862).
Citation rate analysis revealed Portugal as leading country with a rate of
35.47 citations per article, followed by New Zealand and Denmark. Country
cooperation network analyses showed 743 collaborations with US-UK being most
frequent. Network citation analyses indicated the publications that arose from
the cooperation of USA and France as well as USA and Japan as the most cited
(75.36 and 74.55 citations per collaboration article, respectively). The
present study provides the first combined density-equalizing mapping and
scientometric analysis of MRSA research. It illustrates the global MRSA
research architecture. It can be assumed that this highly relevant topic for
public health will achieve even greater dimensions in the future
Standard Versus Natural: Assessing the Impact of Environmental Variables on Organic Matter Decomposition in Streams Using Three Substrates
The decomposition of allochthonous organic matter, such as leaves, is a crucial ecosystem process in low-order streams. Microbial communities, including fungi and bacteria, colonize allochthonous organic material, break up large molecules, and increase the nutritional value for macroinvertebrates. Environmental variables are known to affect microbial as well as macroinvertebrate communities and alter their ability to decompose organic matter. Studying the relationship between environmental variables and decomposition has mainly been realized using leaves, with the drawbacks of differing substrate composition and consequently between-study variability. To overcome these drawbacks, artificial substrates have been developed, serving as standardizable surrogates. In the present study, we compared microbial and total decomposition of leaves with the standardized substrates of decotabs and, only for microbial decomposition, of cotton strips, across 70 stream sites in a Germany-wide study. Furthermore, we identified the most influential environmental variables for the decomposition of each substrate from a range of 26 variables, including pesticide toxicity, concentrations of nutrients, and trace elements, using stability selection. The microbial as well as total decomposition of the standardized substrates (i.e., cotton strips and decotabs) were weak or not associated with that of the natural substrate (i.e., leaves, r(2) < 0.01 to r(2) = 0.04). The decomposition of the two standardized substrates, however, showed a moderate association (r(2) = 0.21), which is probably driven by their similar composition, with both being made of cellulose. Different environmental variables were identified as the most influential for each of the substrates and the directions of these relationships contrasted between the substrates. Our results imply that these standardized substrates are unsuitable surrogates when investigating the decomposition of allochthonous organic matter in streams. Environ Toxicol Chem 2023;00:1-12. (c) 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC
Der Querverbund kommunaler Unternehmen : eine Analyse unter besonderer BerĂĽcksichtigung verfassungs- und europarechtlicher Vorgaben
Die Arbeit untersucht die Zusammenfassung kommunaler Unternehmen in sogenannten Querverbundsunternehmen. Sie befasst sich dabei insbesondere mit den rechtlichen Rahmenbedingungen für die Zuweisung von Finanzmitteln innerhalb des Querverbunds. Von der Zulässigkeit öffentlicher Wirtschaftstätigkeit sowie der organisatorischen Ausgestaltung und ertragssteuerrechtlichen Behandlung des Querverbunds spannt der Autor den Bogen zu grundsätzlichen Fragen des Finanzausgleichsrechts und des europäischen Beihilferechts. Die Untersuchung öffnet so den Blick für das gesamte rechtliche "Koordinatensystem", in dem sich kommunale Querverbundsunternehmen bewegen
A Novel Radiomics-Based Tumor Volume Segmentation Algorithm for Lung Tumors in FDG-PET/CT after 3D Motion Correction—A Technical Feasibility and Stability Study
Positron emission tomography (PET) provides important additional information when applied in radiation therapy treatment planning. However, the optimal way to define tumors in PET images is still undetermined. As radiomics features are gaining more and more importance in PET image interpretation as well, we aimed to use textural features for an optimal differentiation between tumoral tissue and surrounding tissue to segment-target lesions based on three textural parameters found to be suitable in previous analysis (Kurtosis, Local Entropy and Long Zone Emphasis). Intended for use in radiation therapy planning, this algorithm was combined with a previously described motion-correction algorithm and validated in phantom data. In addition, feasibility was shown in five patients. The algorithms provided sufficient results for phantom and patient data. The stability of the results was analyzed in 20 consecutive measurements of phantom data. Results for textural feature-based algorithms were slightly worse than those of the threshold-based reference algorithm (mean standard deviation 1.2%—compared to 4.2% to 8.6%) However, the Entropy-based algorithm came the closest to the real volume of the phantom sphere of 6 ccm with a mean measured volume of 26.5 ccm. The threshold-based algorithm found a mean volume of 25.0 ccm. In conclusion, we showed a novel, radiomics-based tumor segmentation algorithm in FDG-PET with promising results in phantom studies concerning recovered lesion volume and reasonable results in stability in consecutive measurements. Segmentation based on Entropy was the most precise in comparison with sphere volume but showed the worst stability in consecutive measurements. Despite these promising results, further studies with larger patient cohorts and histopathological standards need to be performed for further validation of the presented algorithms and their applicability in clinical routines. In addition, their application in other tumor entities needs to be studied
Silicosis: geographic changes in research: an analysis employing density-equalizing mapping
BACKGROUND: A critical evaluation of scientific efforts is needed in times of modified evaluation criteria for academic personnel and institutions. METHODS: Using scientometric benchmark procedures and density-equalizing mapping, we analysed the global scientific efforts on “silicosis” of the last 92 years focusing on geographical changes within the last 30 years, specifying the most productive authors, institutions, countries and the most successful cooperations. RESULTS: The USA as the most productive supplier have established their position as center of international cooperation, followed in considerable distance by the United Kingdom, Germany and China. Asian countries, particularly China, catch up and are expected to excel the USA still in this decade. CONCLUSION: The combination of scientometric procedures with density-equalizing mapping reveals a distinct global pattern of research productivity and citation activity. Modified h-index, citationrate and impact factor have to be discussed critically due to distortion by bias of self-citation, language and co-authorship