Project description:Despite the rapid growth in the number of scientific publications, our understanding of author publication trajectories remains limited. Here we propose an embedding-based framework for tracking author trajectories in a geometric space that leverages the information encoded in the publication sequences, namely the list of the consecutive publication venues for each scholar. Using the publication histories of approximately 30,000 social media researchers, we obtain a knowledge space that broadly captures essential information about periodicals as well as complex (inter-)disciplinary structures of science. Based on this space, we study academic success through the prism of movement across scientific periodicals. We use a measure from human mobility, the radius of gyration, to characterize individual scholars' trajectories. Results show that author mobility across periodicals negatively correlates with citations, suggesting that successful scholars tend to publish in a relatively proximal range of periodicals. Overall, our framework discovers intricate structures in large-scale sequential data and provides new ways to explore mobility and trajectory patterns.
Project description:Google Scholar (GS) is a free tool that may be used by researchers to analyze citations; find appropriate literature; or evaluate the quality of an author or a contender for tenure, promotion, a faculty position, funding, or research grants. GS has become a major bibliographic and citation database. For assessing the literature, databases, such as PubMed, PsycINFO, Scopus, and Web of Science, can be used in place of GS because they are more reliable. The aim of this study was to examine the accuracy of citation data collected from GS and provide a comprehensive description of the errors and miscounts identified. For this purpose, 281 documents that cited 2 specific works were retrieved via Publish or Perish software (PoP) and were examined. This work studied the false-positive issue inherent in the analysis of neuroimaging data. The results revealed an unprecedented error rate, with 279 of 281 (99.3%) examined references containing at least one error. Nonacademic documents tended to contain more errors than academic publications (U=5117.0; P<.001). This viewpoint article, based on a case study examining GS data accuracy, shows that GS data not only fail to be accurate but also potentially expose researchers, who would use these data without verification, to substantial biases in their analyses and results. Further work must be conducted to assess the consequences of using GS data extracted by PoP.
Project description:INTRODUCTION: Ginsenoside Rg3 is a natural active ingredient that is extracted from Korean red ginseng root. It elevates therapeutic effect of radiotherapy and chemotherapy, but the study found that the application of Rg3 is heavily limited by its low bioavailability and poor absorption via oral administration. METHOD: Rg3-loaded PEG-PLGA-NPs (Rg3-NPs) were prepared by the modified spontaneous emulsification solvent diffusion (SESD) method, and the physicochemical characteristics of Rg3-NPs were investigated in our study. We treated primary glioblastoma with 50 µM Rg3-NPs for 48h. We then used gene expression arrays (Illumina) for genome-wide expression analysis and validated the results for genes of interest by means of Real-Time PCR. Functional annotations were then performed using the DAVID and KEGG online tools. RESULTS: MTT shows that the growth of cells can be significantly inhibited by Rg3-NPs in a dose-dependence manner. FCM test shows Rg3-NPs can be released from the conjugate nanoparticle and react with the genes in the cell nuclei causing changes in the gene molecules. We also found that cancer cells treated with Rg3-NPs undergo cell-cycle arrest at different checkpoints. This arrest was associated with a decrease in the mRNA levels of core regulatory genes as determined by microarray-analysis and verified by Real-Time PCR. Furthermore, Rg3-NPs induced the expression of apoptotic and anti-migratory proteins p53 in cell lines. CONCLUSIONS: The results of the present study, together with the results of earlier studies show that Rg3-NPs targets genes involved in the progression of the M-phase of the cell cycle. It is associated with several important pathways, which include apoptosis (p53). Rg3-NPs may be a potent cell-cycle regulation drug targeting the M-phase in glioblastoma cell lines.
Project description:Objectives: Myocardial fibrosis in noninfarcted myocardium is emerging as a principal phenotype of vulnerability to adverse events such as mortality and hospitalization for heart failure (HHF), but its optimal noninvasive measurement remains uncertain despite consistently robust histologic validation data for extracellular volume fraction (ECV). We therefore compared ECV, native T1, post contrast T1, the gadolinium contrast partition coefficient (lambda), and the presence of nonischemic scar in their associations with mortality and HHF outcomes. Method: To quantify of myocardial fibrosis, we performed T1 mapping (MOLLI) in basal and mid short axis slices with cardiovascular magnetic resonance (CMR) before contrast and 12-30 minutes post contrast bolus in 1185 consecutive patients without amyloidosis, hypertrophic or stress cardiomyopathy. We assessed associations with outcomes using Kaplan-Meier plots and chi square values from univariable Cox regression models. All standard T1 mapping parameters were obtained: native and post contrast myocardial T1, the partition coefficient lambda, and ECV. ECV = (1-hematocrit) · [?R1myocardium]/[?R1bloodpool], where R1 = 1/T1 Late gadolinium enhancement imaging with phase sensitive reconstruction identified nonischemic scar. Results: Over a median of 1.7 years, 111 individuals experienced events after CMR: 55 HHF events and 74 deaths. ECV yielded better separation of Kaplan-Meier curves in a dose dependent fashion (Figure) and also stronger associations with the combined endpoint of death or HHF. The ECV chi square (77.3, p < 0.001) was at least twice as large as the Native T1 chi square (37.5, p < 0.001), the lambda chi square (34.8, p < 0.001) and nonischemic scar (chi square = 20.5, p<0.001). Post-contrast T1 was not associated with outcomes, even when adjusting further for time after contrast bolus, renal function, and patient weight (chi square <3, p >0.10). Conclusion: Analogous to histologic previously published validation data, quantitative ECV myocardial fibrosis measures associated with outcomes far stronger than other surrogate measures outcome measures such as native T1, post contrast T1 and nonischemic scar on LGE images. These data suggest that ECV is the noninvasive metric of choice to measure myocardial fibrosis. Figure. Kaplan-Meier Plots for T1 mapping parameters.