Ultra-high accuracy optical testing: creating diffraction-limitedshort-wavelength optical systems

Since 1993, research in the fabrication of extreme ultraviolet (EUV) optical imaging systems, conducted at Lawrence Berkeley National Laboratory (LBNL) and Lawrence Livermore National Laboratory (LLNL), has produced the highest resolution optical systems ever made. We have pioneered the development of ultra-high-accuracy optical testing and alignment methods, working at extreme ultraviolet wavelengths, and pushing wavefront-measuring interferometry into the 2-20-nm wavelength range (60-600 eV). These coherent measurement techniques, including lateral shearing interferometry and phase-shifting point-diffraction interferometry (PS/PDI) have achieved RMS wavefront measurement accuracies of 0.5-1-{angstrom} and better for primary aberration terms, enabling the creation of diffraction-limited EUV optics. The measurement accuracy is established using careful null-testing procedures, and has been verified repeatedly through high-resolution imaging. We believe these methods are broadly applicable to the advancement of short-wavelength optical systems including space telescopes, microscope objectives, projection lenses, synchrotron beamline optics, diffractive and holographic optics, and more. Measurements have been performed on a tunable undulator beamline at LBNL's Advanced Light Source (ALS), optimized for high coherent flux; although many of these techniques should be adaptable to alternative ultraviolet, EUV, and soft x-ray light sources. To date, we have measured nine prototype all-reflective EUV optical systems with NA values between 0.08 and 0.30 (f/6.25 to f/1.67). These projection-imaging lenses were created for the semiconductor industry's advanced research in EUV photolithography, a technology slated for introduction in 2009-13. This paper reviews the methods used and our program's accomplishments to date

Mucedorus: the last ludic playbook, the first stage Arcadia

This article argues that two seemingly contradictory factors contributed to and sustained the success of the anonymous Elizabethan play Mucedorus (c. 1590; pub. 1598). First, that both the initial composition of Mucedorus and its Jacobean revival were driven in part by the popularity of its source, Philip Sidney's Arcadia. Second, the playbook's invitation to amateur playing allowed its romance narrative to be adopted and repurposed by diverse social groups. These two factors combined to create something of a paradox, suggesting that Mucedorus was both open to all yet iconographically connected to an elite author's popular text. This study will argue that Mucedorus pioneered the fashion for “continuations” or adaptations of the famously unfinished Arcadia, and one element of its success in print was its presentation as an affordable and performable version of Sidney's elite work. The Jacobean revival of Mucedorus by the King's Men is thus evidence of a strategy of engagement with the Arcadia designed to please the new Stuart monarchs. This association with the monarchy in part determined the cultural functions of the Arcadia and Mucedorus through the Interregnum to the close of the seventeenth century

Hydrocarbon ingestions among individuals younger than 20 years old reported to United States Poison Centers, 2000–2021

Abstract Background Hydrocarbon-based products have many household and commercial uses and exposure to these substances is common. Severe clinical effects can occur if these products are ingested. This study investigated the characteristics and trends of hydrocarbon ingestions reported to United States Poison Centers. Methods Data from the National Poison Data System were analyzed for cases of hydrocarbon ingestion among individuals < 20 years old reported to United States Poison Centers from January 1, 2000 through December 31, 2021. Results There were 284,085 hydrocarbon ingestions reported during the 22-year study period in which a hydrocarbon was the first-ranked substance. Most of these cases occurred among children < 6 years old (83.2%), males (64.6%), at a residence (96.5%), were single-substance exposures (98.3%), and were managed on-site rather than in a health care facility (74.9%). However, 4.5% of cases were associated with a serious medical outcome, including 34 deaths. Thirty-two deaths were among children < 6 years old and most were associated with aspiration. Gasolines accounted for 24.6% of total cases, followed by lubricating oils and/or motor oils (19.9%), other types of hydrocarbons (14.9%), lamp oils (11.3%), and lighter fluids and/or naphtha (10.3%). The rate of hydrocarbon ingestions among United States youth < 20 years old decreased significantly (p < 0.0001) by 66.5% from 2000 to 2021. The greatest rate decrease was observed among lamp oils (− 78.4%, p < 0.0001), followed by gasolines (− 75.9%, p < 0.0001). Conclusions Although the rate of hydrocarbon ingestions decreased during the study period and most reported cases resulted in non-serious outcomes, the number of cases remains high with a non-trivial minority (4.5%) of cases associated with a serious medical outcome, including death. Most deaths were among children < 6 years old. This underscores the need to increase primary prevention efforts, especially for young children

Lactic acidosis secondary to metformin overdose: a case report

Introduction Metformin is a commonly used treatment modality in type 2 diabetes mellitus, with a well documented side effect of lactic acidosis. In the intensive care setting lactate and pH levels are regularly used as a useful predictor of poor prognosis. In this article we highlight how high lactate levels are not an accurate predictor of mortality in deliberate metformin overdose. Case presentation We present the case of a 70-year-old Caucasian man who took a deliberate metformin overdose of unknown quantity. He had a profound lactic acidosis at presentation with a pH of 6.93 and a lactate level of more than 20mmol/L. These figures would normally correspond with a mortality of more than 80%; however, with appropriate management this patient’s condition improved. Conclusion We provide evidence that the decision to treat severe lactic acidosis in deliberate metformin overdose should not be based on arterial lactate and pH levels, as would be the case in other overdoses. We also demonstrate that appropriate treatment with hemodiafiltration and 8.4% sodium bicarbonate, even in patients with a very high lactate and low pH, can be successful