Why is invention strongly positively correlated with parental income not only in the US but also in Finland which displays low income inequality and high social mobility? Using data on 1.45M Finnish individuals and their parents, we find that: (i) the positive association between parental income...

We describe how and why Magnetic Resource Imaging (MRI) came to complement – and partially replace -- computed tomography (CT) imaging of soft tissue. Specifically we chronicle: 1) the development of foundational techniques and prototypes (through the 1970s); 2) initial commercialization and...

We describe how the development of x-ray-based techniques and equipment (“mammography”) lead to widespread screening for breast cancer and enabled “minimally invasive” biopsies of breast tumors. Specifically, we chronicle how: 1) new protocols and equipment catalyzed the first widespread...

We describe how efforts on multiple fronts, including advocacy, training and technological development made ultrasound the second most commonly used diagnostic imaging technology (after X-rays). Specifically, we chronicle: 1) ultrasound's development and introduction in the 1950s and 1960s; 2)...