Deciphering the Intricate Control of Minerals on Deep Soil Carbon Stability and Persistence in Alaskan Permafrost.

Understanding the fate of organic carbon in thawed permafrost is crucial for predicting climate feedback. While minerals and microbial necromass are known to play crucial roles in the long-term stability of organic carbon in subsoils, their exact influence on carbon persistence in Arctic permafrost remains uncertain. Our study, combining radiocarbon dating and biomarker analyses, showed that soil organic carbon in Alaskan permafrost had millennial-scale radiocarbon ages and contained only 10%-15% microbial necromass carbon, significantly lower than the global average of ~30%-60%.

Cytomegalovirus Post-Prophylaxis Surveillance in High-Risk Kidney and Liver Recipients Prevents CMV End-Organ Disease and Ganciclovir-Resistance.

Purpose: Evaluate cytomegalovirus (CMV) post-prophylaxis surveillance in high-risk (D+/R-) kidney and liver transplant recipients.

Methods: Adult D+/R- patients were included if transplanted between 6/1/15 and 11/30/22 and divided into a pre-CMV-stewardship-era (6/1/15-5/31/18), CMV-stewardship-era (6/1/18-6/30/20), and a surveillance-era (7/1/2020-11/30/2022) then followed through 12 months. The primary objective was to evaluate CMV-related outcomes.

Characterization of Ssc, an -acetylgalactosamine-containing surface polysaccharide.

Unlabelled: Whole genome sequencing has revealed that the genome of possesses an uncharacterized 5-gene operon (SAOUHSC_00088-00092 in strain 8325 genome) that encodes factors with functions related to polysaccharide biosynthesis and export, indicating the existence of a new extracellular polysaccharide species. We designate this locus as for staphylococcal surface carbohydrate. We found that the genes were weakly expressed and highly repressed by the global regulator MgrA.

Post-fire stabilization of thaw-affected permafrost terrain in northern Alaska.

In 2007, the Anaktuvuk River fire burned more than 1000 km of arctic tundra in northern Alaska, ~ 50% of which occurred in an area with ice-rich syngenetic permafrost (Yedoma). By 2014, widespread degradation of ice wedges was apparent in the Yedoma region. In a 50 km area, thaw subsidence was detected across 15% of the land area in repeat airborne LiDAR data acquired in 2009 and 2014.