Artificial intelligence for diagnosis and Gleason grading of prostate cancer: the PANDA challenge

Artificial intelligence (AI) has shown promise for diagnosing prostate cancer in biopsies. However, results have been limited to individual studies, lacking validation in multinational settings. Competitions have been shown to be accelerators for medical imaging innovations, but their impact is hindered by lack of reproducibility and independent validation. With this in mind, we organized the PANDA challenge—the largest histopathology competition to date, joined by 1,290 developers—to catalyze development of reproducible AI algorithms for Gleason grading using 10,616 digitized prostate biopsies. We validated that a diverse set of submitted algorithms reached pathologist-level performance on independent cross-continental cohorts, fully blinded to the algorithm developers. On United States and European external validation sets, the algorithms achieved agreements of 0.862 (quadratically weighted κ, 95% confidence interval (CI), 0.840–0.884) and 0.868 (95% CI, 0.835–0.900) with expert uropathologists. Successful generalization across different patient populations, laboratories and reference standards, achieved by a variety of algorithmic approaches, warrants evaluating AI-based Gleason grading in prospective clinical trials.

The Impact of Size on the Performance of Transnational Corporations Operating in the Textile Industry in Portugal during the COVID-19 Pandemic

The aim of this work is to understand the impact of size on the performance of transnational corporations (TNCs) operating in the textile and clothing industry in Portugal during the COVID-19 pandemic. For this purpose, we used ORBIS data for the period 2019–2020 and narrative, financial and correlation analyses to assess the performance of five companies. Thus far, the impact of company size on the competitiveness of Portuguese textile affiliates during the pandemic has remained unexplored. The results show that smaller firms performed better than larger ones, likely due to the higher fixed costs of the latter at times when orders declined worldwide. Our analysis suggests that there are some characteristics of TNCs that matter in explaining company-level performance during crises, such as management experience and flexibility. Furthermore, as Portugal is a major European textile exporter, it is useful for the host country to assess the economic sustainability of its foreign investors. The results provide some policy recommendations regarding the promotion of foreign direct investment (FDI) in Portugal.

hyper.deal: An Efficient, Matrix-free Finite-element Library for High-dimensional Partial Differential Equations

This work presents the efficient, matrix-free finite-element library hyper.deal for solving partial differential equations in two up to six dimensions with high-order discontinuous Galerkin methods. It builds upon the low-dimensional finite-element library deal.II to create complex low-dimensional meshes and to operate on them individually. These meshes are combined via a tensor product on the fly, and the library provides new special-purpose highly optimized matrix-free functions exploiting domain decomposition as well as shared memory via MPI-3.0 features. Both node-level performance analyses and strong/weak-scaling studies on up to 147,456 CPU cores confirm the efficiency of the implementation. Results obtained with the library hyper.deal are reported for high-dimensional advection problems and for the solution of the Vlasov–Poisson equation in up to six-dimensional phase space.

The emerging association of canonical finger patterns and quantity-number linkage in early childhood

Through repeated use of fingers for counting and representing numerical magnitudes in early childhood, specific finger patterns become associated with mental representations of specific quantities. Although children as young as three years of age already use their fingers for representing numerical quantities, evidence on advantageous recognition of such canonical compared to non-canonical finger patterns as well as its association with numerical skills in young children is scarce. In this study, we investigated the performance of N=101 children aged around four years in canonical vs. non-canonical finger pattern recognition and its concurrent association with skills tapping into children’s’ knowledge about quantity-number linkage. Extending previous findings observed for older children, the present results indicated that despite considerable variability on the individual level performance in canonical finger pattern recognition was better compared to non-canonical finger pattern recognition on the group level. Moreover, both canonical and non-canonical finger pattern recognition was positively correlated with tasks tapping into quantity-number linkage. However, when controlling for verbal counting skills, correlations that remained significant were only found for canonical but not non-canonical finger pattern recognition performance. Overall, these results provide insights into the early onset and significance of the effect of canonicity in finger pattern recognition during early numerical development.

Representative Bureaucracy, Institutional Support, and Clientele Need: The Case of Undocumented Students

The theory of representative bureaucracy posits that passive representation is associated with improvements in policy outcomes for represented groups. This research examines the institutional conditions under which representative bureaucracy is enhanced or limited. It posits that the benefits of representation will be enhanced when institutional supports are stronger and when clientele need is greatest. Using a unique longitudinal, multi-level dataset, this paper tests competing theoretical conditions (including resource constraints, and task difficulty) under which representative bureaucracy is enhanced or constrained. The analysis tracks student-level performance of 400,000 undocumented students in Texas public schools from 2003 to 2011 providing a powerful empirical test as well as practical policy implications for administrators. It finds that the effects of representation are strongest when resources are abundant and clientele need is greatest. This suggests representative may be even more valuable to organizations than previously thought.

Development of a Simulation Surgical Cricothyroidotomy Curriculum for Novice Providers: A Learning Curve Study

ABSTRACT Introduction Airway obstruction is the third most common cause of preventable death on the battlefield, accounting for 1%–2% of total combat fatalities. No previous surgical cricothyroidotomy (SC) studies have analyzed the learning curve required to obtain proficiency despite being studied in numerous other surgical technique training experiments. The aims of this study were to establish expert SC performance criteria, develop a novel standardized SC curriculum, and determine the necessary number of practice iterations required by a novice to reach this pre-determined performance goal. Materials and Methods A standardized checklist and SC performance standards were established based on the performance of 12 board certified Military Health System surgeons with prior experience on performing a SC using a simulated trauma mannequin. Expert-level criteria were defined as a SC time to completion of 40 s or less and checklist score of at least 9/10, including all critical steps. Study subjects included 89 novice providers (54 active-duty first- and second-year medical students and 35 Navy corpsmen). Subjects received instruction on performing a SC using the principles of mastery learning and performed a final test of SC proficiency on a trauma mannequin within a realistic simulated MEDEVAC helicopter. The total number of subject practice attempts, checklist scores, and time to completion were measured and/or blindly scored. Learning curve and exponential plateau equations were used to characterize their improvement in mean time to SC completion and checklist scores. Results Mean pre-test knowledge scores for the entire group were 11.8 ± 3.1 out of 24 points. Total mean practice learning plateaued at checklist scores of 9.9/10 after 7 iterations and at a mean completion time of 30.4 s after 10 iterations. During the final test performance in the helicopter, 67.4% of subjects achieved expert-level performance on the first attempt. All subjects achieved expert-level performance by the end of two additional attempts. While a significantly larger proportion of medical students (79.9%) successfully completed the helicopter test on the first attempt compared to corpsmen (54.3%), there were no statistically significant differences in mean SC completion times and checklist scores between both groups (P > 0.05). Medical students performed a SC only 1.3 s faster and scored only 0.16 points higher than corpsmen. The effect size for differences were small to negligible (Cohen’s d range 0.18–0.33 for SC completion time; Cohen’s d range 0.45–0.46 for checklist scores). Conclusion This study successfully defined SC checklist scores and completion times based on the performance of experienced surgeons on a simulator. Using these criteria and the principles of mastery learning, novices with little knowledge and experience in SC were successfully trained to the level of experienced providers. All subjects met performance targets after training and overall performance plateaued after approximately seven iterations. Over two-thirds of subjects achieved the performance target on the first testing attempt in a simulated helicopter environment. Performance was comparable between medical student and corpsmen subgroups. Further research will assess the durability of maintaining SC skills and the timing for introducing refresher courses after initial skill acquisition.

How Does Improvement in Commuting Affect Employees? Evidence from a Natural Experiment

We collect worker month-level panel data from two companies for a two-year period before and after the opening of a nearby subway station, which significantly improved public transportation commutes for some workers. We find a significant difference-in-differences increase (12.6% of the standard deviation) in bonus pay (which is strongly correlated to worker-level performance measures) for affected workers relative to unaffected coworkers. We find no evidence that the improved performance is a result of affected workers spending extra time at the workplace. We find suggestive evidence for a relative decline in turnover, consistent with a gain in utility for affected workers.