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Abstract Ratios of glycerol dialkyl glycerol tetraethers (GDGT), which are membrane lipids of bacteria and archaea, are at the base of several paleoenvironmental proxies. They are frequently applied to soils as well as lake‐ and marine sediments to generate records of past temperature and soil pH. To derive meaningful environmental information from these reconstructions, high analytical reproducibility is required. Based on submitted results by 39 laboratories from across the world, which employ a diverse range of analytical and quantification methods, we explored the reproducibility of brGDGT‐based proxies (MBT′5ME, IR, and #ringstetra) measured on four soil samples and four soil lipid extracts. Correct identification and integration of 5‐ and 6‐methyl brGDGTs is a prerequisite for the robust calculation of proxy values, but this can be challenging as indicated by the large inter‐interlaboratory variation. The exclusion of statistical outliers improves the reproducibility, where the remaining uncertainty translates into a temperature offset from median proxy values of 0.3–0.9°C and a pH offset of 0.05–0.3. There is no apparent systematic impact of the extraction method and sample preparation steps on the brGDGT ratios. Although reported GDGT concentrations are generally consistent within laboratories, they vary greatly between laboratories. This large variability in brGDGT quantification may relate to variations in ionization efficiency or specific mass spectrometer settings possibly impacting the response of brGDGTs masses relative to that of the internal standard used. While ratio values of GDGT are generally comparable, quantities can currently not be compared between laboratories.

Abstract Objective Define current practices and protocols in surgical training programs for pregnant trainees. Study Design Cross sectional. Setting Academic surgical training programs in the United States. Methods A validated 20‐question survey was sent via email to program directors and coordinators of US surgical training programs, including otolaryngology head & neck surgery (OHNS), plastic surgery, vascular surgery, and general surgery. The survey was issued in November and December 2022 and data were collected until January 2023. This study was approved for exemption by the Minimal Risk Research IRB at the University of Wisconsin Madison (ID number 2022‐1370). Results Surveys were emailed to 608 surgical programs, and the response rate was 23.5% (143/608) including 45 OHNS programs. When asked if their program has a policy in place for pregnant trainees, 84.4% responded yes, and 82.4% responded that they were satisfied with their policy. Subsequent questions addressed individual policies and risk factors facing pregnant trainees. 60.3% of programs report providing protected time off for miscarriages. Only 36.9% provide information to pregnant trainees regarding workplace exposures that pose a risk of fetal anomaly or miscarriage. Only 47.1% incorporate rest breaks for pregnant trainees, and only 20% protect the number of hours a pregnant trainee operates per week. 24.2% adjust overnight shifts or call schedules for pregnant trainees, and of those that adjust call shifts, 20% require pregnant trainees to “make up” these missed call shifts. Less than half (40%) of programs have a contingency plan in place for supporting nonchild‐bearing residents who may take on the work of their colleagues during pregnancy or postpartum. Conclusion While a majority of training programs report a pregnancy policy in place for trainees, most of these policies appear to be severely deficient in addressing critical aspects of surgical training that place both fetus and mother at significant risk of complications. This data indicates a need for a safe pregnancy protocol in order to protect both surgeon and fetus.

Premise Cañahua is a semi‐domesticated crop grown in high‐altitude regions of the Andes. It is an A‐genome diploid (2n = 2x = 18) relative of the allotetraploid (AABB) Chenopodium quinoa and shares many of its nutritional benefits. Cañahua seed contains a complete protein, a low glycemic index, and offers a wide variety of nutritionally important vitamins and minerals. Methods The reference assembly was developed using a combination of short‐ and long‐read sequencing techniques, including multiple rounds of Hi‐C–based proximity‐guided assembly. Results The final assembly of the ~363‐Mbp genome consists of 4633 scaffolds, with 96.6% of the assembly contained in nine scaffolds representing the nine haploid chromosomes of the species. Repetitive element analysis classified 52.3% of the assembly as repetitive, with the most common repeat identified as long terminal repeat retrotransposons. MAKER annotation of the final assembly yielded 22,832 putative gene models. Discussion When compared with quinoa, strong patterns of synteny support the hypothesis that cañahua is a close A‐genome diploid relative, and thus potentially a simplified model diploid species for genetic analysis and improvement of quinoa. Resequencing and phylogenetic analysis of a diversity panel of cañahua accessions suggests that coordinated efforts are needed to enhance genetic diversity conservation within ex situ germplasm collections.