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In science, mentees often follow their mentors' career paths, but exceptional mentees frequently break from this routine, sometimes even outperforming their mentors. However, the pathways to independence for these excellent mentees and their interactions with mentors remain unclear. We analyzed the careers of over 500,000 mentees in Chemistry, Neuroscience, and Physics over the past 60 years to examine the strategies mentees employ in selecting research topics relative to their mentors, how these strategies evolve, and their resulting impact. Utilizing co-citation network analysis and a topic-specific impact allocation algorithm, we mapped the topic territory for each mentor-mentee pair and quantified their academic impact accrued within the topic. Our findings reveal mentees tend to engage with their mentors' less-dominated topics and explore new topics at the same time, and through this exaptive process, they begin to progressively establish their own research territories. This trend is particularly pronounced among those who outperform their mentors. Moreover, we identified an inverted U-shaped curve between the extent of topic divergence and the mentees' long-term impact, suggesting a moderate divergence from the mentors' research focus optimizes the mentees' academic impact. Finally, along the path to independence, increased coauthorship with mentors impedes the mentees' impact, whereas extending their collaboration networks with the mentors' former collaborators proves beneficial. These findings fill a crucial gap in understanding how mentees' research topic selection strategies affect academic success and offer valuable guidance for early-career researchers on pursuing independent research paths., Comment: 20 pages, 5 figures

Understanding the evolution of scholarly impact is essential for many real-life decision-making processes in academia, such as research planning, frontier exploration, and award selection. Popular platforms like Google Scholar and Web of Science rely on numerical indicators that are too abstract to convey the context and content of scientific impact, while most existing visualization approaches on mapping science do not consider the presentation of individual scholars' impact evolution using curated self-citation data. This paper builds on our previous work and proposes an integrated pipeline to visualize a scholar's impact evolution from multiple topic facets. A novel 3D prism-shaped visual metaphor is introduced as the overview of a scholar's impact, whilst their scientific evolution on each topic is displayed in a more structured manner. Additional designs by topic chord diagram, streamgraph visualization, and inter-topic flow map, optimized by an elaborate layout algorithm, assist in perceiving the scholar's scientific evolution across topics. A new six-degree-impact glyph metaphor highlights key interdisciplinary works driving the evolution. The proposed visualization methods are evaluated through case studies analyzing the careers of prestigious Turing award laureates and a major visualization venue., Comment: 13 pages, 8 figures, excluding appendix. Submitted to TVCG on 20240813

We report on the first measurement of the elemental fragmentation cross sections (EFCSs) of $^{29-33}\mathrm{Si}$ on a carbon target at $\sim$230~MeV/nucleon. The experimental data covering charge changes of $\Delta Z$ = 1-4 are reproduced well by the isospin-dependent quantum molecular dynamics (IQMD) coupled with the evaporation GEMINI (IQMD+GEMINI) model. We further explore the mechanisms underlying the single-proton removal reaction in this model framework. We conclude that the cross sections from direct proton knockout exhibit a overall weak dependence on the mass number of $\mathrm{Si}$ projectiles. The proton evaporation induced after the projectile excitation significantly affects the cross sections for neutron-deficient $\mathrm{Si}$ isotopes, while neutron evaporation plays a crucial role in the reactions of neutron-rich $\mathrm{Si}$ isotopes. It is presented that the relative magnitude of one-proton and one-neutron separation energies is an essential factor that influences evaporation processes., Comment: 7 pages, 4 figures

The Great Gatsby Curve measures the relationship between income inequality and intergenerational income persistence. By utilizing genealogical data of over 245,000 mentor-mentee pairs and their academic publications from 22 different disciplines, this study demonstrates that an academic Great Gatsby Curve exists as well, in the form of a positive correlation between academic impact inequality and the persistence of impact across academic generations. We also provide a detailed breakdown of academic persistence, showing that the correlation between the impact of mentors and that of their mentees has increased over time, indicating an overall decrease in academic intergenerational mobility. We analyze such persistence across a variety of dimensions, including mentorship types, gender, and institutional prestige.

After 2009 many governments implemented austerity measures, often restricting science funding. Did such restrictions further skew grant income towards elite scientists and universities? And did increased competition for funding undermine participation? UK science funding agencies significantly reduced numbers of grants and total grant funding in response to austerity, but surprisingly restrictions of science funding were relaxed after the 2015 general election. Exploiting this natural experiment, we show that conventional measures of university competitiveness are poor proxies for competitiveness. An alternative measure of university competitiveness, drawn from complexity science, captures the highly dynamical way in which universities engage in scientific subjects. Building on a data set of 43,430 UK funded grants between 2006 and 2020, we analyse rankings of UK universities and investigate the effect of research competitiveness on grant income. When austerity was relaxed in 2015 the elasticity of grant income w.r.t. research competitiveness fell, reflecting increased effort by researchers at less competitive universities. These scientists increased number and size of grant applications, increasing grant income. The study reveals how funding agencies, facing heterogeneous competitiveness in the population of scientists, affect research effort across the distribution of competitiveness.

How difficult is it for an early career academic to climb the ranks of their discipline? We tackle this question with a comprehensive bibliometric analysis of 57 disciplines, examining the publications of more than 5 million authors whose careers started between 1986 and 2008. We calibrate a simple random walk model over historical data of ranking mobility, which we use to (1) identify which strata of academic impact rankings are the most/least mobile and (2) study the temporal evolution of mobility. By focusing our analysis on cohorts of authors starting their careers in the same year, we find that ranking mobility is remarkably low for the top and bottom-ranked authors, and that this excess of stability persists throughout the entire period of our analysis. We further observe that mobility of impact rankings has increased over time, and that such rise has been accompanied by a decline of impact inequality, which is consistent with the negative correlation that we observe between such two quantities. These findings provide clarity on the opportunities of new scholars entering the academic community, with implications for academic policymaking.

On-surface synthesis (OSS) involving relatively high energy barriers remains challenging due to a typical dilemma: firm molecular anchor is required to prevent molecular desorption upon the reaction, whereas sufficient lateral mobility is crucial for subsequent coupling and assembly. By locking the molecular precursors on the substrate then unlocking them during the reaction, we present a strategy to address this challenge. High-yield synthesis based on well-defined decarboxylation, intermediate transition and hexamerization is demonstrated, resulting in an extended and ordered network exclusively composed of the newly-synthesized macrocyclic compound. Thanks to the steric hindrance of its maleimide group, we attain a preferential selection of the coupling. This work unlocks a promising path to enrich the reaction types and improve the coupling selectivity hence the structual homogeneity of the final product for OSS.