No abstract

In this paper, we address the question as to whether or not measurable sources for gravitational waves could possibly be made in the laboratory. Based on an analogy of the dynamical Casimir effect with the stimulated emission of radiation in the laser, our answer to this question is in the affirmative, provided that superconducting radio-frequency cavities in fact possess high quality factors for both electromagnetic and gravitational microwave radiation, as one would expect due to a quantum-mechanical gravitational Meissner-like effect. In order to characterize the response of matter to tensor gravitational fields, we introduce a prefactor to the source term of the gravitational wave equation, which we call the "relative gravitational permeativity" analogous to the "relative electric permittivity" and "relative magnetic permeability" that characterize the vector response of matter to applied fields in electromagnetism. This allows for a possibly large quantum mechanical enhancement of the response of a superconductor to an incident tensor gravitational wave field. Finally, we describe our experimental work with high-Q superconducting radio-frequency cavities, and propose a design for a coupled-cavity system with a flexible superconducting membrane in its middle as its amplifying element. This will then allow us to test for a Meissner-like expulsion, and therefore reflection, of incident tensor gravitational wave fields, and, above a certain threshold, to generate coherent gravitational radiation via the dynamical Casimir effect.

Molecular Adsorbent Recirculating System (MARS) is a liver support system widely employed in the treatment of liver failure. The method is normally well tolerated. To develop a liver support system combining high efficiency and tolerability, we modified the MARS albumin circuit with the insertion of double adsorption units in parallel. Four patients have been treated with this modified method (high-efficiency MARS, HE MARS): two had very high serum bilirubin and two had very high total bile acids. After a single MARS session bilirubin was reduced more with HE MARS than standard MARS (from 27.6 to 52.3% in patient A and from 27.9 to 49.1% in patient B), and bile acid reduction increased from 40 to 59.8% in patient C and from 39.9 to 60% in patient D. The results of this preliminary investigation in only a very small number of patients do support the possibility of developing a liver support system that combines good tolerability and high efficacy.

Superconducting circuit testing and materials loss characterization requires robust and reliable methods for the extraction of internal and coupling quality factors of microwave resonators. A common method, imposed by limitations on the device design or experimental configuration, is the single-port reflection geometry, i.e. reflection-mode. However, impedance mismatches in cryogenic systems must be accounted for through calibration of the measurement chain while it is at low temperatures. In this paper, we demonstrate a data-based, single-port calibration using commercial microwave standards and a vector network analyzer with samples at millikelvin temperature in a dilution refrigerator, making this method useful for measurements of quantum phenomena. Finally, we cross reference our data-based, single-port calibration and reflection measurement with over-coupled 2D-and 3D-resonators against well established two-port techniques corroborating the validity of our method.

The clinical impact of anti-spike monoclonal antibodies (mAb) in Coronavirus Disease 2019 (COVID-19) breakthrough infections is unclear. We present the results of an observational prospective cohort study assessing and comparing COVID-19 progression in high-risk outpatients receiving mAb according to primary or breakthrough infection. Clinical, serological and virological predictors associated with 28-day COVID-19-related hospitalization were identified using multivariate logistic regression and summarized with odds ratio (aOR) and 95% confidence interval (CI). A total of 847 COVID-19 outpatients were included: 414 with primary and 433 with breakthrough infection. Hospitalization was observed in 42/414 (10.1%) patients with primary and 8/433 (1.8%) patients with breakthrough infection (p < 0.001). aOR for hospitalization was significantly lower for breakthrough infection (aOR 0.12, 95%CI: 0.05–0.27, p < 0.001) and higher for immunocompromised status (aOR:2.35, 95%CI:1.08–5.08, p = 0.003), advanced age (aOR:1.06, 95%CI: 1.03–1.08, p < 0.001), and male gender (aOR:1.97, 95%CI: 1.04–3.73, p = 0.037). Among the breakthrough infection group, the median SARS-CoV-2 anti-spike IgGs was lower (p < 0.001) in immunocompromised and elderly patients >75 years compared with that in the immunocompetent patients. Our findings suggest that, among mAb patients, those with breakthrough infection have significantly lower hospitalization risk compared with patients with primary infection. Prognostic algorithms combining clinical and immune-virological characteristics are needed to ensure appropriate and up-to-date clinical protocols targeting high-risk categories.