Between the 1880s and 1910s, thousands of African Americans passed civil service exams and became employed in the executive offices of the federal government. However, by 1920, promotions to ...well-paying federal jobs had nearly vanished for black workers. Eric S. Yellin argues that the Wilson administration's successful 1913 drive to segregate the federal government was a pivotal episode in the age of progressive politics. Yellin investigates how the enactment of this policy, based on Progressives' demands for whiteness in government, imposed a color line on American opportunity and implicated Washington in the economic limitation of African Americans for decades to come.Using vivid accounts of the struggles and protests of African American government employees, Yellin reveals the racism at the heart of the era's reform politics. He illuminates the nineteenth-century world of black professional labor and social mobility in Washington, D.C., and uncovers the Wilson administration's progressive justifications for unraveling that world. From the hopeful days following emancipation to the white-supremacist "normalcy" of the 1920s, Yellin traces the competing political ideas, politicians, and ordinary government workers who created "federal segregation."
We describe recent experiments using a SuperCDMS high-voltage single-charge sensitive (HVeV) detector illuminated with an ultraviolet LED (275 nm) and a monochromatic laser (650 nm) using a ...dual-fiber optic system installed in a small dilution refrigerator at Stanford University. We observed a population of fluorescence background events after UV exposure but not after exposure to the laser source. The fluorescence was likely due to scattered UV photons absorbed outside the detector. We discuss the possibility of fluorescence being a contributor to the low energy excess background observed in above-ground Dark Matter experiments.
We present direct imaging measurements of charge transport across a 1 cm × 1 cm × 4 mm-thick crystal of high purity silicon (∼15 kΩ-cm) at temperatures of 5 K and 500 mK. We use these data to measure ...lateral diffusion of electrons and holes as a function of the electric field applied along the 111 crystal axis and to verify our low-temperature Monte Carlo software. The range of field strengths in this paper exceed those used in our previous study R. A. Moffatt et al., Appl. Phys. Lett. 114, 032104 (2019) by a factor of 10 and now encompass the region in which some recent silicon dark matter detectors operate R. Agnese et al., Phys. Rev. Lett. 121, 051301 (2018). We also report on a phenomenon of surface charge trapping, which can reduce expected charge collection.
A model for charge trapping and impact ionization and an experiment to measure these parameters are presented for the SuperCDMS HVeV detector. A procedure to isolate and quantify the main sources of ...noise (bulk and surface charge leakage) in the measurements is also described. This sets the stage to precisely measure the charge trapping and impact ionization probabilities in order to incorporate this model into future dark matter searches.
To analyse publication and citations trends of case reports within otolaryngology - head and neck surgery literature, with specific attention to the most-cited reports.Study designDatabase query.
Web ...of Science was searched for article type 'case reports' published in the leading otolaryngology - head and neck surgery journals since 1945. Variables including publication dates, citation dates and numbers, author, author number, and others were recorded and analysed for trends. The reports with the most citations (classics) were further studied.
Of nearly 67 000 published articles in leading otolaryngology - head and neck surgery journals, the overall number of case reports as a percentage of the total has substantially decreased over time. A total of 110 case report classics were identified for which citations have increased.
Although the case report may not be worthy of its tarnished record, declining trends in publication suggest a limited future for this valuable research and educational resource.