Ultrathin Magnesium-Based Coating as an Efficient Oxygen Barrier for Superconducting Circuit Materials.

Scaling up superconducting quantum circuits based on transmon qubits necessitates substantial enhancements in qubit coherence time. Over recent years, tantalum (Ta) has emerged as a promising candidate for transmon qubits, surpassing conventional counterparts in terms of coherence time. However, amorphous surface Ta oxide layer may introduce dielectric loss, ultimately placing a limit on the coherence time. In this study, a novel approach for suppressing the formation of tantalum oxide using an ultrathin magnesium (Mg) capping layer is presented. Synchrotron-based X-ray photoelectron spectroscopy studies demonstrate that oxide is confined to an extremely thin region directly beneath the Mg/Ta interface. Additionally, it is demonstrated that the superconducting properties of thin Ta films are improved following the Mg capping, exhibiting sharper and higher-temperature transitions to superconductive and magnetically ordered states. Moreover, an atomic-scale mechanistic understanding of the role of the capping layer in protecting Ta from oxidation is established based on computational modeling. This work provides valuable insights into the formation mechanism and functionality of surface tantalum oxide, as well as a new materials design principle with the potential to reduce dielectric loss in superconducting quantum materials. Ultimately, the findings pave the way for the realization of large-scale, high-performance quantum computing systems.

Physical Activity and Health Among Native Hawaiian and other Pacific Islander Older Adults.

Objectives: Native Hawaiian and other Pacific Islander (NHPI) older adults often experience social disadvantages and poor health outcomes. Physical activity has been associated with better health in other racial groups, but limited studies have examined these associations in NHPI older adults. Methods: Using data from the 2014 Native Hawaiian and Pacific Islander National Health Interview Survey (n = 1,045), logistic regression models examined associations between physical activity and memory/psychological distress/self-rated health. Results: Sufficient levels of physical activity were associated with lower odds of memory problems, serious psychological distress, and poor/fair self-rated health. Unfortunately, only half of the sample reported sufficient physical activity and approximately 30% reported none. Also, 78% of the sample was estimated to be overweight/obese, and 29% had diabetes. Discussion: Culturally-appropriate interventions are recommended to increase physical activity in this population, which could also help reduce high rates of overweight/obesity and diabetes.

Long-Term Survival Outcomes of Cytoreductive Nephrectomy Combined with Targeted Therapy for Metastatic Renal Cell Carcinoma: A Systematic Review and Individual Patient Data Meta-Analysis.

The role of cytoreductive nephrectomy (CN) in the treatment of metastatic renal cell carcinoma (mRCC) remains controversial during the targeted therapy era. To reconcile the current literature, we analyzed the reported survival data at the individual patient level and compared the long-term survival outcomes of CN combined with targeted therapy vs. targeted therapy alone in patients with mRCC. We performed a systematic review of the literature using the MEDLINE, Scopus, and Cochrane Library databases (end-of-search date: 21 July 2020). We recuperated individual patient data from the Kaplan-Meier curves for overall (OS), progression-free (PFS), and cancer-specific survival (CSS) from each study. We subsequently performed one-stage frequentist and Bayesian random-effects meta-analyses using both Cox proportional hazards and restricted mean survival time (RMST) models. Two-stage random-effects meta-analyses were also performed as sensitivity analyses. A subgroup analysis was also performed to determine the effect of CN timing. Fifteen studies fulfilling our inclusion criteria were identified, including fourteen retrospective cohort studies and one randomized controlled trial. In the one-stage frequentist meta-analysis, the CN group had superior OS (hazard ratio [HR]: 0.58, 95% confidence interval [CI]: 0.54-0.62, p < 0.0001) and CSS (HR: 0.63, 95% CI: 0.53-0.75, p < 0.0001). No meaningful clinical difference was observed in PFS (HR: 0.90, 95% CI: 0.80-1.02, p = 0.09). One-stage Bayesian meta-analysis also revealed superior OS (HR: 0.59, 95% credibility interval [CrI]: 0.55-0.63) and CSS (HR: 0.63, 95% CrI: 0.53-0.75) in the CN group, while no meaningful clinical difference was detected in PFS (HR: 0.91, 95% CrI: 0.80-1.02). Similar results were obtained with the RMST models. The OS benefit was also noted in the two-stage meta-analyses models, and in the subgroup of patients who received upfront CN. The combination of CN and targeted therapy for mRCC may lead to superior long-term survival outcomes compared to targeted therapy alone. Careful patient selection based on prognostic factors is required to optimize outcomes.

The prenylated dioxopiperazine alkaloid Cristatin A has selective telomeric DNA G-quadruplex stabilising properties.

Cristatin A (1a/b), a prenylated dioxopiperazine alkaloid, has been shown to bind selectively to telomeric quadruplex DNA using a FRET-based DNA melting assay. Crucially, the molecule is more drug-like than most previously identified quadruplex-binding agents, and provides a unique chemical scaffold for future chemical biology and drug discovery studies.