Personalized brain stimulation for effective neurointervention across participants.

Accumulating evidence from human-based research has highlighted that the prevalent one-size-fits-all approach for neural and behavioral interventions is inefficient. This approach can benefit one individual, but be ineffective or even detrimental for another. Studying the efficacy of the large range of different parameters for different individuals is costly, time-consuming and requires a large sample size that makes such research impractical and hinders effective interventions. Here an active machine learning technique is presented across participants-personalized Bayesian optimization (pBO)-that searches available parameter combinations to optimize an intervention as a function of an individual's ability. This novel technique was utilized to identify transcranial alternating current stimulation (tACS) frequency and current strength combinations most likely to improve arithmetic performance, based on a subject's baseline arithmetic abilities. The pBO was performed across all subjects tested, building a model of subject performance, capable of recommending parameters for future subjects based on their baseline arithmetic ability. pBO successfully searches, learns, and recommends parameters for an effective neurointervention as supported by behavioral, simulation, and neural data. The application of pBO in human-based research opens up new avenues for personalized and more effective interventions, as well as discoveries of protocols for treatment and translation to other clinical and non-clinical domains.

Probabilistic numerics and uncertainty in computations.

We deliver a call to arms for probabilistic numerical methods: algorithms for numerical tasks, including linear algebra, integration, optimization and solving differential equations, that return uncertainties in their calculations. Such uncertainties, arising from the loss of precision induced by numerical calculation with limited time or hardware, are important for much contemporary science and industry. Within applications such as climate science and astrophysics, the need to make decisions on the basis of computations with large and complex data have led to a renewed focus on the management of numerical uncertainty. We describe how several seminal classic numerical methods can be interpreted naturally as probabilistic inference. We then show that the probabilistic view suggests new algorithms that can flexibly be adapted to suit application specifics, while delivering improved empirical performance. We provide concrete illustrations of the benefits of probabilistic numeric algorithms on real scientific problems from astrometry and astronomical imaging, while highlighting open problems with these new algorithms. Finally, we describe how probabilistic numerical methods provide a coherent framework for identifying the uncertainty in calculations performed with a combination of numerical algorithms (e.g. both numerical optimizers and differential equation solvers), potentially allowing the diagnosis (and control) of error sources in computations.

Medical climatology in France: the persistence of Neo-Hippocratic ideas in the first half of the twentieth century.

In interwar France the Lyonnais physician Marius Piéry undertook an ambitious Neo-Hippocratic research program to study how atmospheric and terrestrial environments influenced health. Lyon had a number of institutions linked to the colonies and was a center for the training of military physicians. Colonial physicians had a long tradition of contending with the diseases of tropical environments, and their ideas and many returned colonials circulated in Lyon and its region. Piéry was a physician during World War I and published on military medical topics. He also included colonial and military health concerns in his more mature works from the 1930s. An advocate of the close study of the physical sciences, he investigated the radioactive gases of health spas and the effects of altitude on pulmonary tuberculosis, and he directed a meteorological observatory.

Science and the French Empire.

Scholarly interest in French colonial science, interpreted to include colonial medical and scientific institutions as well as personages and other "actors" in France serving colonial agendas, has been robust for some two decades. This essay characterizes the complex and interlinked historical relationships between French metropolitan and colonial science as one of asymmetric coevolution. In analyzing scholarship on diverse topics from physics and military technology to colonial botany, medicine, geography, and racial theory, it interrogates the concepts of French nation and French empire and questions the historiographical and explanatory utility of the core-periphery model. Special scrutiny falls on a trope common to historigraphical studies of the postrevolutionary era, that of a firm French nationalism enabling largely rational colonial agendas and the promotion of these agendas by highly centralized Parisian bureaucracies. The essay calls for a reading of French history inclusive of regional colonialist activities and argues for the prevalence of municipal and regional maritime, technological, scientific, and military interests in constructing the modern French empire.

Views from the periphery: discourses of race and place in French military medicine.

Numerous authors have interpreted the history of anthropological and medical conceptions of race in nineteenth century France as following a path mapped out by phrenology, anthropometry, and Paul Broca's version of physical anthropology. On balance, this has resulted in an historical narrative centered on Parisian intellectual life and one leaving the impression that by the 1890s anthropological theories had moved away from ethnological and cultural explanations toward more biological views of race. This article, by contrast, examines the world beyond Paris and the literatures of naval and army medicine from about 1830 to 1920. It describes the contours of a medical and anthropological pluralism in matters of race and ethnicity and argues that cultural and ethnological perspectives remained important to theorists of race through World War I.