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Abstract Water years (WY) 2017 and 2023 were anomalously wet for California, each alleviating multiyear drought. In both cases, this was unexpected given La Niña conditions, with most seasonal forecasts favoring drier‐than‐normal winters. We analyze over seven decades of precipitation and snow records along with mid‐tropospheric circulation to identify recurring weather patterns driving California precipitation and Sierra Nevada snowpack. Tropical forcing by ENSO causes subtle but important differences in these wet weather patterns, which largely drives the canonical seasonal ENSO‐precipitation relationship. However, the seasonal frequency of these weather patterns is not strongly modulated by ENSO and remains a primary source of uncertainty for seasonal forecasting. Seasonal frequency of ENSO‐independent weather patterns was a major cause of anomalous precipitation in WY2017, record‐setting snow in WY2023, and differences in precipitation outcome during recent El Niño winters 1983, 1998, and 2016. Improved understanding of recurrent atmospheric weather patterns could help to improve seasonal precipitation forecasts.

Exponentially growing publication rates are increasingly problematic for interdisciplinary fields like Critical Zone (CZ) science. How does one “keep up” across different, but related fields with unique hypotheses, field techniques, and models? By surveying CZ academics in the Western US, a region with substantial CZ research, we document the challenge. While conventional knowledge synthesis products-particularly review papers clearly support knowledge transfer, they are static and limited in scope. More informal paths for knowledge transfer, including social networking at conferences and academic mentorship, are useful but are unstructured and problematic for young scientists or others who may not have access to these resources. While new machine-learning tools, including ChatGPT, offer new ways forward for knowledge synthesis, we argue that they do not necessarily solve the problem of information overload in CZ Science. Instead, we argue that what we need is a community driven, machine aided knowledge tool that evolves and connects, but preserves the richness of detail found in peer-reviewed papers. The platform would be designed by CZ scientists, machine-aided and built on the strengths of people-driven synthesis. By involving the scientist in the design of this tool, it will better reflect the practice of CZ science-including hypothesis generation, testing across different time and space scales and in different time periods and locations, and, importantly, the use and evaluation of multiple, often sophisticated methods including fieldwork, remote sensing, and modeling. We seek a platform design that increases the findability and accessibility of current working knowledge while communicating the CZ science practice.

Our objective was to quantify the efficacy of paclobutrazol substrate drenches on growth of nine black-eyed Susan (Rudbeckia hirta) cultivars. Liners of ‘Autumn Colors’, ‘Cherokee Sunset’, ‘Cherry Brandy’, ‘Denver Daisy’, ‘Glowing’, ‘Happy’, ‘Indian Summer’, ‘Prairie Sun’, and ‘Sunny’ black-eyed Susan were transplanted into 6.5-inch-diameter plastic containers (2 qt) filled with a commercial soilless peat-based substrate. After 16 days, six single-plant replicates received a substrate drench of 5-fl-oz aliquots of solutions containing deionized water [0 mg·L−1 paclobutrazol (control)] or 2.5, 5, 10, or 20 mg·L−1 paclobutrazol (0, 0.375, 0.75, 1.5, and 3.0 mg/pot). Paclobutrazol drenches of 2.5 to 20 mg·L−1 significantly influenced plant height, plant diameter, growth index (GI), and shoot dry weight (SDW) of all black-eyed Susan cultivars, although the magnitude of response to paclobutrazol substrate drench concentration varied with cultivar. For most cultivars, GI, an integrated measurement of height and diameter, was suppressed as paclobutrazol substrate drench concentrations increased from 2.5 to 20 mg·L−1, resulting in plants that were 30% to 43% smaller than untreated plants. Increasing paclobutrazol substrate drench concentrations from 2.5 to 20 mg·L−1 limited SDW of each cultivar differently, although plants were 5% to 59% smaller at 20 mg·L−1 paclobutrazol than untreated plants. Time to flower for ‘Autumn Colors’, ‘Cherry Brandy’, ‘Happy’, ‘Indian Summer’, and ‘Prairie Sunset’ was unaffected by any paclobutrazol substrate drench concentration; however, concentrations of ≤10 mg·L−1 paclobutrazol are suggested for ‘Cherokee Sunset’, ‘Denver Daisy’, ‘Glowing’, and ‘Sunny’, as higher concentrations delay flowering. Our results indicate that growers can attain growth control with substrate drenches containing 5 to 10 mg·L−1 paclobutrazol during greenhouse black-eyed Susan production without delaying flowering.

Abstract Background Carp gudgeons (genus Hypseleotris) are a prominent part of the Australian freshwater fish fauna, with species distributed around the western, northern, and eastern reaches of the continent. We infer a calibrated phylogeny of the genus based on nuclear ultraconserved element (UCE) sequences and using Bayesian estimation of divergence times, and use this phylogeny to investigate geographic patterns of diversification with GeoSSE. The southeastern species have hybridized to form hemiclonal lineages, and we also resolve relationships of hemiclones and compare their phylogenetic placement in the UCE phylogeny with a hypothesis based on complete mitochondrial genomes. We then use phased SNPs extracted from the UCE sequences for population structure analysis among the southeastern species and hemiclones. Results Hypseleotris cyprinoides, a widespread euryhaline species known from throughout the Indo-Pacific, is resolved outside the remainder of the species. Two Australian radiations comprise the bulk of Hypseleotris, one primarily in the northwestern coastal rivers and a second inhabiting the southeastern region including the Murray–Darling, Bulloo-Bancannia and Lake Eyre basins, plus coastal rivers east of the Great Dividing Range. Our phylogenetic results reveal cytonuclear discordance between the UCE and mitochondrial hypotheses, place hemiclone hybrids among their parental taxa, and indicate that the genus Kimberleyeleotris is nested within the northwestern Hypseleotris radiation along with three undescribed species. We infer a crown age for Hypseleotris of 17.3 Ma, date the radiation of Australian species at roughly 10.1 Ma, and recover the crown ages of the northwestern (excluding H. compressa) and southeastern radiations at 5.9 and 7.2 Ma, respectively. Range-dependent diversification analyses using GeoSSE indicate that speciation and extinction rates have been steady between the northwestern and southeastern Australian radiations and between smaller radiations of species in the Kimberley region and the Arnhem Plateau. Analysis of phased SNPs confirms inheritance patterns and reveals high levels of heterozygosity among the hemiclones. Conclusions The northwestern species have restricted ranges and likely speciated in allopatry, while the southeastern species are known from much larger areas, consistent with peripatric speciation or allopatric speciation followed by secondary contact. Species in the northwestern Kimberley region differ in shape from those in the southeast, with the Kimberley species notably more elongate and slender than the stocky southeastern species, likely due to the different topographies and flow regimes of the rivers they inhabit.

Abstract Increasing wildfire and declining snowpacks in mountain regions threaten water availability. We combine satellite‐based fire detections with snow seasonality classifications to examine fire activity in California's seasonal and ephemeral snow zones. We find a nearly tenfold increase in fire activity during 2020–2021 versus 2001–2019. Accumulation season broadband snow albedo declined 25%–71% at two burned sites (2021 and 2022) according to in‐situ data relative to un‐burned conditions, with greater declines associated with increased burn severity. By enhancing snowpack susceptibility to melt, both decreased snow albedo and canopy drove midwinter melt during a multi‐week dry spell in 2022. Despite similar meteorological conditions in December–February 2013 and 2022–linked to persistent high pressure weather regimes–minimal melt occurred in 2013. Post‐fire snowpack differences are confirmed with satellite measurements. With growing geographical overlap between wildfire and snow, our findings suggest California's snowpack is increasingly vulnerable to the compounding effects of dry spells and wildfire.

Abstract Study objectives This study investigated the interrater reliability of the history component of the HEART (history, electrocardiogram, age, risk, troponin) score between physicians in emergency medicine (EM) and internal medicine (IM) at 1 tertiary‐care center. Methods We conducted a retrospective, secondary analysis of 60 encounters selected randomly from a database of 417 patients with chest pain presenting from January to June 2016 to an urban tertiary‐care center. A total of 4 raters (1 EM attending, 1 EM resident, 1 IM attending, and 1 IM resident) scored the previously abstracted history data from these encounters. The primary outcome was the interrater agreement of HEART score history components, as measured by kappa coefficient, between EM and IM attending physicians. Secondary outcomes included the agreement between attending and resident physicians, overall agreement, pairwise percent agreement, and differences in scores assigned. Results The kappa value for the EM attending physician and IM attending physician was 0.33 with 55% agreement. Interrater agreement of the other pairs was substantial between EM attending and resident but was otherwise fair to moderate. Percent agreement between the other pairs ranged from 48.3% to 80%. There was a significant difference in scores assigned and the subgroup in which there was disagreement between the raters demonstrated significantly higher scores by the EM attending and resident when compared to the IM attending. Conclusion This study demonstrates fair agreement between EM and IM attending physicians in the history component of the HEART score with significantly higher scores by the EM attending physician in cases of disagreement at 1 tertiary‐care center.

Mountain rain-on-snow (ROS) generates large flooding events worldwide. Climate warming will enhance the frequency, magnitude, and widespread nature of these events. Past studies indicate rainfall, not snowmelt, typically drives much of the runoff response during ROS. However, there is substantial event-to-event variability—resulting from shifting atmospheric drivers and nuanced physical mechanisms governing water flow through a snowpack. Historically, turbulent fluxes were assumed to dominate the energy balance for snowmelt during ROS. Recent research nonetheless suggests that other components of the energy balance might be larger drivers depending on: 1) the time of year; 2) the elevation; and 3) the aspect of the slope. This mini review summarizes the literature on the physical processes governing ROS and proposes that moving forward we utilize the terms “active” and “passive” to describe a snowpack’s contribution (via snowmelt) to terrestrial water input (TWI) during ROS. Active snowpacks readily contribute meltwater to TWI via the energy balance, bolstering rainfall-runoff totals. Passive snowpacks do not melt, but simply convey rainwater through the snow matrix. In both snowpack cases, preferential flow paths enhance transmissivity. This proposed classification scheme will help researchers and water managers better communicate and interpret past findings, and aid in forecasting discussions of future events.

Abstract Background Advances in genomics technologies are making it increasingly feasible to characterize breeding lines that carry traits of agronomic interest. Tobacco germplasm lines that carry loci designated VAM and va have been extensively investigated due to their association with potyvirus resistance (both VAM and va) and defects in leaf surface compounds originating from glandular trichomes (VAM only). Molecular studies and classical genetic analyses are consistent with the model that VAM and va represent deletion mutations in the same chromosomal region. In this study, we used RNA-seq analysis, together with emerging tobacco reference genome sequence information to characterize the genomic regions deleted in tobacco lines containing VAM and va. Results Tobacco genotypes TI 1406 (VAM), K326-va and K326 (wild type) were analyzed using RNA-seq to generate a list of genes differentially expressed in TI 1406 and K326-va, versus the K326 control. Candidate genes were localized onto tobacco genome scaffolds and validated as being absent in only VAM, or missing in both VAM and va, through PCR analysis. These results enabled the construction of a map that predicted the relative extent of the VAM and va mutations on the distal end of chromosome 21. The RNA-seq analyses lead to the discovery that members of the cembratrienol synthase gene family are deleted in TI 1406. Transformation of TI 1406 with a cembratrienol synthase cDNA, however, did not recover the leaf chemistry phenotype. Common to both TI 1406 and K326-va was the absence of a gene encoding a specific isoform of a eukaryotic translation initiation factor (eiF4E1.S). Transformation experiments showed that ectopic expression of eiF4E1.S is sufficient to restore potyvirus susceptibility in plants possessing either the va or VAM mutant loci. Conclusions We have demonstrated the feasibility of using RNA-seq and emerging whole genome sequence resources in tobacco to characterize the VAM and va deletion mutants. These results lead to the discovery of genes underlying some of the phenotypic traits associated with these historically important loci. Additionally, initial size estimations were made for the deleted regions, and dominant markers were developed that are very close to one of the deletion junctions that defines va.

Girls and women face persistent negative stereotyping within STEM (science, technology, engineering, mathematics). This field intervention was designed to improve boys' perceptions of girls' STEM ability. Boys (N = 667; mostly White and East Asian) aged 9-15 years in Canadian STEM summer camps (2017-2019) had an intervention or control conversation with trained camp staff. The intervention was a multi-stage persuasive appeal: a values affirmation, an illustration of girls' ability in STEM, a personalized anecdote, and reflection. Control participants discussed general camp experiences. Boys who received the intervention (vs. control) had more positive perceptions of girls' STEM ability, d = 0.23, an effect stronger among younger boys. These findings highlight the importance of engaging elementary-school-aged boys to make STEM climates more inclusive.

Increasing wildfire and declining snowpacks in mountain regions threaten water availability. We combine satellite-based fire detections with snow seasonality classifications to examine fire activity in California's seasonal and ephemeral snow zones. We find a nearly tenfold increase in fire activity during 2020–2021 versus 2001–2019. Accumulation season broadband snow albedo declined 25%–71% at two burned sites (2021 and 2022) according to in-situ data relative to un-burned conditions, with greater declines associated with increased burn severity. By enhancing snowpack susceptibility to melt, both decreased snow albedo and canopy drove midwinter melt during a multi-week dry spell in 2022. Despite similar meteorological conditions in December–February 2013 and 2022–linked to persistent high pressure weather regimes–minimal melt occurred in 2013. Post-fire snowpack differences are confirmed with satellite measurements. With growing geographical overlap between wildfire and snow, our findings suggest California's snowpack is increasingly vulnerable to the compounding effects of dry spells and wildfire.

Common practice and conventional wisdom hold that fluctuations in air temperature control interannual variability in snowmelt and subsequent river runoff. However, recent observations in the Upper Colorado River Basin confirm that net solar radiation and by extension radiative forcing by dust deposited on snow cover exerts the primary forcing on snowmelt. We show that the variation in the shape of the rising limb of the annual hydrograph is controlled by variability in dust radiative forcing and surprisingly is independent of variations in winter and spring air temperatures. These observations suggest that hydroclimatic modeling must be improved to account for aerosol forcings of the water cycle. Anthropogenic climate change will likely reduce total snow accumulations and cause snowmelt runoff to occur earlier. However, dust radiative forcing of snowmelt is likely consuming important adaptive capacity that would allow human and natural systems to be more resilient to changing hydroclimatic conditions.

Targeted mutant models are common in mechanistic toxicology experiments investigating the absorption, metabolism, distribution, or elimination (ADME) of chemicals from individuals. Key models include those for xenosensing transcription factors and cytochrome P450s (CYP). Here we investigated changes in transcript levels, protein expression, and steroid hydroxylation of several xenobiotic detoxifying CYPs in constitutive androstane receptor (CAR)-null and two CYP-null mouse models that have subfamily members regulated by CAR; the Cyp3a-null and a newly described Cyp2b9/10/13-null mouse model. Compensatory changes in CYP expression that occur in these models may also occur in polymorphic humans, or may complicate interpretation of ADME studies performed using these models. The loss of CAR causes significant changes in several CYPs probably due to loss of CAR-mediated constitutive regulation of these CYPs. Expression and activity changes include significant repression of Cyp2a and Cyp2b members with corresponding drops in 6α- and 16β-testosterone hydroxylase activity. Further, the ratio of 6α-/15α-hydroxylase activity, a biomarker of sexual dimorphism in the liver, indicates masculinization of female CAR-null mice, suggesting a role for CAR in the regulation of sexually dimorphic liver CYP profiles. The loss of Cyp3a causes fewer changes than CAR. Nevertheless, there are compensatory changes including gender-specific increases in Cyp2a and Cyp2b. Cyp2a and Cyp2b were down-regulated in CAR-null mice, suggesting activation of CAR and potentially PXR following loss of the Cyp3a members. However, the loss of Cyp2b causes few changes in hepatic CYP transcript levels and almost no significant compensatory changes in protein expression or activity with the possible exception of 6α-hydroxylase activity. This lack of a compensatory response in the Cyp2b9/10/13-null mice is probably due to low CYP2B hepatic expression, especially in male mice. Overall, compensatory and regulatory CYP changes followed the order CAR-null > Cyp3a-null > Cyp2b-null mice.

Water years (WY) 2017 and 2023 were anomalously wet for California, each alleviating multiyear drought. In both cases, this was unexpected given La Niña conditions, with most seasonal forecasts favoring drier‐than‐normal winters. We analyze over seven decades of precipitation and snow records along with mid‐tropospheric circulation to identify recurring weather patterns driving California precipitation and Sierra Nevada snowpack. Tropical forcing by ENSO causes subtle but important differences in these wet weather patterns, which largely drives the canonical seasonal ENSO‐precipitation relationship. However, the seasonal frequency of these weather patterns is not strongly modulated by ENSO and remains a primary source of uncertainty for seasonal forecasting. Seasonal frequency of ENSO‐independent weather patterns was a major cause of anomalous precipitation in WY2017, record‐setting snow in WY2023, and differences in precipitation outcome during recent El Niño winters 1983, 1998, and 2016. Improved understanding of recurrent atmospheric weather patterns could help to improve seasonal precipitation forecasts. Plain Language Summary: In 2017 and 2023, California experienced unexpectedly wet conditions despite predictions of dry winters due to La Niña. In 2016, seasonal predictions in California favored wet conditions due to the very strong El Niño, but the season was normal‐to‐dry statewide. Understanding relationships between El Niño/La Niña and recurring atmospheric weather patterns driving individual storms is needed to improve seasonal forecasts. We studied historical relationships between weather patterns that bring rain and snow to the region and the El Niño Southern Oscillation (ENSO). We find ENSO influences important characteristics of weather patterns once they make landfall in California, making El Niño storms generally wetter in coastal southern California and Desert Southwest. However, ENSO does not strongly affect how often these patterns occur in a season, which makes seasonal precipitation forecasts challenging. The frequency of certain weather patterns not tied to ENSO played important roles in the unusual rainfall of 2017, the heavy snowfall of 2023, and the drier than expected winter of 2016. Understanding these weather patterns provides operationally and scientifically relevant context for future seasonal forecasts by highlighting that while ENSO only minimally influences the frequency of certain impactful storm types, it does change the precipitation characteristics of these storms. Key Points: Weather regime type and frequency are key drivers of winter seasons with anomalous precipitation and/or snow accumulation in CaliforniaENSO does not modulate the seasonal frequency of weather regimes impacting the coast, presenting a challenge for seasonal forecastingENSO modulates synoptic circulation characteristics of key weather regimes which produces the canonical ENSO‐precipitation relationship [ABSTRACT FROM AUTHOR]

Sixteen coleus (Coleus scutellarioides) cultivars (genotypes) with four cultivars representing four industry-categorized color groups [phenotypes (Burgundy, Orange, Red, and Yellow/Green)] were evaluated to determine if leaf color affected tissue nutrient concentrations. Plants were grown at two locations provided with a liquid fertilizer concentration of 150 mg.L−1 N delivered from 17 N–1.31P–14.1K. Leaf tissue samples were collected and analyzed for the concentration of 12 elemental nutrients after eight or 10 wk of growth, depending on location. Leaf tissue nutrient concentrations were influenced by leaf color (color groups), but the magnitude varied for each elemental nutrient. Leaf tissue nutrient concentrations were significantly different for each color group for phorphorus (P), potassium (K), calcium, magnesium, iron, copper and boron, but not for nitrogen, sulfur, manganese, or zinc. Trends for higher P and K leaf tissue concentrations in Red-leaf coleus cultivars, and lower P in Yellow/Green cultivars agree with prior work reported for Heuchera sp. This data further support the initial foundational work to determine the relationship between leaf color and tissue nutrient concentration. Further investigations among other species may offer additional data that will help establish a relative relationship between an element and phenotypes. Given the wide variation in leaf tissue concentrations across all 16 cultivars, an overall consolidated data set was developed to provide a refinement of the leaf tissue nutrient standards for coleus across all elements. This expands the recommended ranges available for interpreting leaf tissue samples, which will assist growers and crop advisors in diagnosing nutrient disorders of coleus. [ABSTRACT FROM AUTHOR]