Pump-probe capabilities at the SPB/SFX instrument of the European XFEL.

Pump-probe experiments at X-ray free-electron laser (XFEL) facilities are a powerful tool for studying dynamics at ultrafast and longer timescales. Observing the dynamics in diverse scientific cases requires optical laser systems with a wide range of wavelength, flexible pulse sequences and different pulse durations, especially in the pump source. Here, the pump-probe instrumentation available for measurements at the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument of the European XFEL is reported. The temporal and spatial stability of this instrumentation is also presented.

The Single Particles, Clusters and Biomolecules and Serial Femtosecond Crystallography instrument of the European XFEL: initial installation.

The European X-ray Free-Electron Laser (FEL) became the first operational high-repetition-rate hard X-ray FEL with first lasing in May 2017. Biological structure determination has already benefitted from the unique properties and capabilities of X-ray FELs, predominantly through the development and application of serial crystallography. The possibility of now performing such experiments at data rates more than an order of magnitude greater than previous X-ray FELs enables not only a higher rate of discovery but also new classes of experiments previously not feasible at lower data rates. One example is time-resolved experiments requiring a higher number of time steps for interpretation, or structure determination from samples with low hit rates in conventional X-ray FEL serial crystallography. Following first lasing at the European XFEL, initial commissioning and operation occurred at two scientific instruments, one of which is the Single Particles, Clusters and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument. This instrument provides a photon energy range, focal spot sizes and diagnostic tools necessary for structure determination of biological specimens. The instrumentation explicitly addresses serial crystallography and the developing single particle imaging method as well as other forward-scattering and diffraction techniques. This paper describes the major science cases of SPB/SFX and its initial instrumentation - in particular its optical systems, available sample delivery methods, 2D detectors, supporting optical laser systems and key diagnostic components. The present capabilities of the instrument will be reviewed and a brief outlook of its future capabilities is also described.

Outcomes of a home telemonitoring program for SARS-CoV-2 viral infection at a large academic medical center.

INTRODUCTION: Telemedicine serves as a viable option during the COVID-19 pandemic to provide in-home care, maintain home isolation precautions, reduce unnecessary healthcare exposures, and de-burden hospitals. METHODS: We created a novel telemedicine program to closely monitor patients infected with SARS-CoV-2 (COVID-19) at home. Adult patients with COVID-19 were enrolled in the program at the time of documented infection. Patients were followed by a team of providers via telephone or video visits at frequent intervals until resolution of their acute illness. Additionally, patients were stratified into high-risk and low-risk categories based on demographics and underlying comorbidities. The primary outcome was hospitalization after enrollment in the home monitoring program, including 30 days after discharge from the program. RESULTS: Over a 3.5-month period, 1128 patients met criteria for enrollment in the home monitoring program. 30.7% were risk stratified as high risk for poor outcomes based on their comorbidities and age. Of the 1128 patients, 6.2% required hospitalization and 1.2% required ICU admission during the outcome period. Hospitalization was more frequent in patients identified as high risk (14.2% vs 2.7%, P < 0.001). DISCUSSION: Enrollment in a home monitoring program appears to be an effective and sustainable modality for the ambulatory management of COVID-19.

EUS and ERCP complication rates are not increased in elderly patients.

BACKGROUND: Further studies evaluating the safety of advanced endoscopic procedures in elderly patients are needed. AIM: To evaluate the safety of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) in the elderly. METHODS: The study population, consisting of 1,000 patients who underwent ERCP or EUS, was divided into two cohorts. The elderly cohort consisted of patients ≥ 75 years old. The nonelderly cohort consisted of patients <75 years old. The data collected included demographic information, type of procedure completed, procedure medication used, and endoscopic intervention performed. Complications included any event which occurred during the procedure or up to 1 month post procedure. RESULTS: A total of 600 ERCPs and 400 EUS were included. The mean age of the elderly cohort was 80 years (range 75-95 years, n = 184) versus 54 years (range 13-74 years, n = 816) for the nonelderly cohort. The ERCP complication rate was 10.0% in the elderly versus 10.6% (P = 1.0) for the nonelderly. The EUS complication rate was 4.8% in the elderly versus 3.1% in the nonelderly (P = 0.49). The overall complication rates were identical at 7.6% (P = 1.0). Sedation doses were lower for the elderly cohort (P < 0.001). There was a higher rate of procedure bleeding in the elderly cohort (P = 0.016). CONCLUSION: Advanced age is not a contraindication for advanced endoscopic procedures. There is no significant increase in the rate of overall procedure-related complications seen with either ERCP or EUS in elderly patients; however, elderly patients have a higher risk of bleeding. Less procedure-related sedation medication is required for elderly patients.