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This paper provides an overview of the United States (US) Department of Energy's (DOE's) Energy Exascale Earth System Model version 2 (E3SMv2) fully coupled regionally refined model (RRM) and documents the overall atmosphere, land, and river results from the Coupled Model Intercomparison Project 6 (CMIP6) DECK (Diagnosis, Evaluation, and Characterization of Klima) and historical simulations – a first-of-its-kind set of climate production simulations using RRM. The North American (NA) RRM (NARRM) is developed as the high-resolution configuration of E3SMv2 with the primary goal of more explicitly addressing DOE's mission needs regarding impacts to the US energy sector facing Earth system changes. The NARRM features finer horizontal resolution grids centered over NA, consisting of 25→100 km atmosphere and land, a 0.125∘ river-routing model, and 14→60 km ocean and sea ice. By design, the computational cost of NARRM is ∼3× of the uniform low-resolution (LR) model at 100 km but only ∼ 10 %–20 % of a globally uniform high-resolution model at 25 km.A novel hybrid time step strategy for the atmosphere is key for NARRM to achieve improved climate simulation fidelity within the high-resolution patch without sacrificing the overall global performance. The global climate, including climatology, time series, sensitivity, and feedback, is confirmed to be largely identical between NARRM and LR as quantified with typical climate metrics. Over the refined NA area, NARRM is generally superior to LR, including for precipitation and clouds over the contiguous US (CONUS), summertime marine stratocumulus clouds off the coast of California, liquid and ice phase clouds near the North Pole region, extratropical cyclones, and spatial variability in land hydrological processes. The improvements over land are related to the better-resolved topography in NARRM, whereas those over ocean are attributable to the improved air–sea interactions with finer grids for both atmosphere and ocean and sea ice. Some features appear insensitive to the resolution change analyzed here, for instance the diurnal propagation of organized mesoscale convective systems over CONUS and the warm-season land–atmosphere coupling at the southern Great Plains. In summary, our study presents a realistically efficient approach to leverage the fully coupled RRM framework for a standard Earth system model release and high-resolution climate production simulations.

Emissions‐driven (prognostic CO2) simulations are essential for representing two‐way carbon‐climate feedback in Earth System Models. We present an emissions‐driven land–atmosphere coupled biogeochemistry (BGC) configuration (BGCLNDATM_progCO2) in version 2.1 of the Energy Exascale Earth System Model (E3SMv2.1). This is the first E3SM configuration that performs land‐atmosphere emission‐hindcasts. Here, we document its implementation, evaluate the model's performance against observations and other models, and propose a structured evaluation protocol for such emissions‐driven simulations. We conducted transient historical simulations (1850–2014) with BGCLNDATM_progCO2 and compare them to reference simulations—a land‐atmosphere coupled simulation without BGC and a standalone land simulation with BGC, both using prescribed CO2 concentrations—and to observations. BGCLNDATM_progCO2 overestimates atmospheric CO2 concentrations by 11–23 ppm yet stays within the 40‐ppm spread CMIP6 emission‐driven models and retains physical climate properties comparable to the reference runs. The CO2 biases are partly attributed to underrepresented oceanic CO2 uptake and inadequate representations of some terrestrial processes. In general, introducing prognostic CO2 did not change physical climate metrics at the global scale but had larger regional effects, particularly over land where spatially heterogeneous CO2 and prognostic leaf area index influenced surface energy balance. Finally, we propose a general evaluation protocol including spin‐up assessment, atmospheric CO2 benchmarking, physical climate evaluation, and land biogeochemical analysis to support scientific rigor and facilitate inter‐model comparisons. The new configuration lays the groundwork for future enhancements, including improved terrestrial biogeochemical processes, integrated marine biogeochemistry, and additional human–Earth system interactions. These developments advance E3SM toward fully coupled emissions‐driven simulations, enabling more accurate carbon–climate feedback projections and informing mitigation policy by providing physically consistent carbon‐budget metrics for mitigation scenarios. Plain Language Summary Understanding the impact of carbon dioxide (CO2) emissions on climate is vital for predicting future changes and crafting effective policies. Earth System Models (ESMs) are essential tools for simulating Earth's climate and assessing various influencing factors. In this study, we extended the Energy Exascale Earth System Model (E3SM)'s capabilities so that CO2 levels are calculated directly from human and natural emissions instead of being prescribed as a single global value. This extension allows for a more realistic representation of CO2 exchange between the atmosphere and land. We conducted historical simulations from 1850 to 2014 using this new development and compared results with observations and other models. Our model slightly overestimates atmospheric CO2 levels compared to measurements but is comparable to other models in capturing key climate features. To help other researchers build and test similar “emission‐driven” models, we created a step‐by‐step evaluation framework that checks CO2 behavior, climate variables, and land‐atmosphere interactions. Our work advances E3SM modeling by accurately representing how CO2 emissions affect Earth's systems. This enhancement lays the groundwork for modeling interactions between human‐Earth interactions, thereby enabling future studies that can inform mitigation and adaption. Key Points Implemented emissions‐driven land–atmosphere biogeochemistry in E3SMv2.1 (BGCLNDATM_progCO2), enabling prognostic CO2 simulations Established a structured evaluation protocol ensuring scientific rigor and facilitating inter‐model comparisons of model performance Emissions‐driven BGCLNDATM_progCO2 simulations maintain a physical climate similar to reference runs with prescribed CO2 concentrations

This work documents version two of the Department of Energy's Energy Exascale Earth System Model (E3SM). E3SMv2 is a significant evolution from its predecessor E3SMv1, resulting in a model that is nearly twice as fast and with a simulated climate that is improved in many metrics. We describe the physical climate model in its lower horizontal resolution configuration consisting of 110 km atmosphere, 165 km land, 0.5° river routing model, and an ocean and sea ice with mesh spacing varying between 60 km in the mid‐latitudes and 30 km at the equator and poles. The model performance is evaluated with Coupled Model Intercomparison Project Phase 6 Diagnosis, Evaluation, and Characterization of Klima simulations augmented with historical simulations as well as simulations to evaluate impacts of different forcing agents. The simulated climate has many realistic features of the climate system, with notable improvements in clouds and precipitation compared to E3SMv1. E3SMv1 suffered from an excessively high equilibrium climate sensitivity (ECS) of 5.3 K. In E3SMv2, ECS is reduced to 4.0 K which is now within the plausible range based on a recent World Climate Research Program assessment. However, a number of important biases remain including a weak Atlantic Meridional Overturning Circulation, deficiencies in the characteristics and spectral distribution of tropical atmospheric variability, and a significant underestimation of the observed warming in the second half of the historical period. An analysis of single‐forcing simulations indicates that correcting the historical temperature bias would require a substantial reduction in the magnitude of the aerosol‐related forcing. Plain Language Summary The U.S. Department of Energy recently released version two of its Energy Exascale Earth System Model (E3SM). E3SMv2 experienced a significant evolution in many of its model components (most notably the atmosphere and sea ice models), and its supporting software infrastructure. In this work, we document the computational performance of E3SMv2 and analyze its ability to reproduce the observed climate. To accomplish this, we utilize the standard Diagnosis and Evaluation and Characterization of Klima experiments augmented with historical simulations for the period 1850–2015. We find that E3SMv2 is nearly twice as fast as its predecessor and more accurately reproduces the observed climate in a number of metrics, most notably clouds and precipitation. We also find that the model's simulated response to increasing carbon dioxide (the equilibrium climate sensitivity) is much more realistic. Unfortunately, E3SMv2 underestimates the global mean surface temperature compared to observations during the second half of historical period. Using sensitivity experiments, where forcing agents (carbon dioxide, aerosols) are selectively disabled in the model, we determine that correcting this problem would require a strong reduction in the impact of aerosols. Key Points E3SMv2 is nearly twice as fast as E3SMv1 with a simulated climate that is improved in many metrics (e.g., precipitation and clouds) Climate sensitivity is substantially lower with a more plausible equilibrium climate sensitivity of 4.0 K (compared to an unlikely value of 5.3 K in E3SMv1) E3SMv2 underestimates the warming in the late historical period due to excessive aerosol‐related forcing

A growing, global conversation, regarding realities and challenges that parents experience today is ever-present. To understand recent parent’s attitudes, beliefs, and perceptions regarding infant feeding, we sought to systematically identify and synthesize original qualitative research findings. Following the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) framework, electronic databases were searched with a priori terms applied to title/abstract fields and limited to studies published in English from 2015 to 2019, inclusive. Study quality assessment was conducted using the Critical Appraisal Skills Programme (CASP) checklist, and thematic analyses performed. Of 73 studies meeting inclusion criteria, four major themes emerged. (1) Breastfeeding is best for an infant; (2) Distinct attitudes, beliefs, and perceptions of mothers that breastfeed, and those that could not or chose not to breastfeed, are evident; (3) Infant feeding behaviors are influenced by the socio-cultural environment of the family, and (4) Parent’s expectations of education and support addressing personal infant feeding choices from health care providers are not always met. This systematic review, guided by constructs within behavioral models and theories, provides updated findings to help inform the development of nutrition education curricula and public policy programs. Results can be applied within scale-up nutrition and behavioral education interventions that support parents during infant feeding.

This study contributes to the development of a positive framework for effective public schools in 2 ways. First, it advances the construct self-regulatory climate as consisting of 3 generative school norms-collective faculty trust in students, collective student trust in teachers, and student-perceived academic emphasis. The authors argue these norms signal a school climate supportive of student psychological needs. Second, they test the predictive validity of self-regulatory climate by empirically examining its relationship with school performance. Results of structural equation modeling support the theory that collective faculty trust in students, collective student trust in teachers, and student-perceived academic emphasis combine to form a self-regulatory climate that has positive consequences for urban school performance.

IntroductionThis study reports the 30-day mortality, SARS-CoV-2 complication rate and SARS-CoV-2-related hospital processes at the peak of the first wave of the pandemic in the UK.MethodsThis national, multicentre, cohort study at 74 centres in the UK included all patients undergoing any surgery below the elbow at the peak of the UK pandemic. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The secondary outcomes were SARS-CoV-2 complication rates and overall complication rates. A clinician survey relating to SARS-CoV-2 safety processes was carried out for each participating centre.ResultsThis analysis includes 1093 patients who underwent upper limb surgery from the 1 to 14 April 2020 inclusively. The overall 30-day mortality was 0.09% (1 pre-existing SARS-CoV-2 pneumonia) and the mortality of day case surgery was zero. Most centres (96%) screened patients for symptoms prior to admission, only 22% routinely tested for SARS-CoV-2 prior to admission. The SARS-CoV-2 complication rate was 0.18% (2 pneumonias) and the overall complication rate was 6.6% (72 patients). Both SARS-CoV-2-related complications occurred in patients who had been hospitalised for a prolonged period before their surgery and a total of 19 patients (1.7%) were SARS-CoV-2 positive.ConclusionsThe SARS-CoV-2-related complication rate for upper limb surgery even at the peak of the UK pandemic was low at 0.18% and the mortality was zero for patients admitted on the day of surgery. Urgent surgery should not be delayed pending the results of SARS-CoV-2 testing. Routine SARS-CoV-2 testing for day case upper limb surgery not requiring general anaesthesia may be excessive and have unintended negative impacts.

The preparation of ruthenium complexes with novel 2,2′‐bipyridine (bpy) ligands bearing four carboxylic acid groups was investigated with a view to creating dyes containing more than two potential anchoring groups per bpy unit for attachment to a titania surface. Synthetic challenges are encountered upon using the 2,2′‐bipyridine‐3,3′,4,4′‐tetracarboxylic acid ligand because it readily decarboxylates. The use of the methyl esterified derivative (3) proved to be more successful for complex preparation, with a robust preparation of the [Ru(3)2Cl2] complex identified with diglyme as the solvent. This complex was further converted into the thiocyanato complex, [Ru(3)2(NCS)2], which could not be completely de‐esterified. X‐ray analysis of crystals obtained from a mixture of isomers for this complex provided data for the S,S‐ and N,S‐coordinated isomers; both showed a twisted arrangement of the pyridine rings in the 2,2′‐bipyridine‐3,3′,4,4′‐tetracarboxylic acid ligand, owing to steric hinderance. Conversely, the isosteric 2,2′‐bipyridine‐4,4′,5,5′‐tetracarboxylic acid ligand was easily converted into the desired [Ru(2)2(NCS)2] complex through a standard one‐pot procedure in N,N‐dimethylformamide solvent. All of the complexes presented herein exhibit a significant redshift for the metal to ligand charge‐transfer bands, relative to the benchmark ruthenium dye N719 and derivatives thereof. All complexes exhibit a quasi‐reversible process for the ruthenium(II/III) couple at approximately 0.4 V versus the ferrocene couple, comparable to analogous ruthenium dyes. Shifting the absorption limit: Homoleptic ruthenium dyes carrying four carboxylate groups per 2,2′‐bipyridine (bpy) ligand were synthesized. In these analogues to classical N3 and N719 dyes, the additional carboxylate groups at bpy positions 3 and 3′ cause the torsion angle of the aromatic rings to increases to almost 35° (see figure) from an almost planar arrangement in N3, and a redshift in the UV/Vis absorptions of the metal to ligand charge‐transfer bands.

In addition to its role in genome protection, DNA methylation can regulate gene expression. In this study, we characterized the impact of acidity, phase variation, and the ArsRS TCS on the expression of the Type I m6A DNA methyltransferase HsdM1 (HP0463) of Helicobacter pylori 26695 and their subsequent effects on the methylome. Transcription of hsdM1 increases at least 4-fold in the absence of the sensory histidine kinase ArsS, the major acid-sensing protein of H. pylori. hsdM1 exists in the phase-variable operon hsdR1-hsdM1. Phase-locking hsdR1 (HP0464), the restriction endonuclease gene, has significant impacts on the transcription of hsdM1. To determine the impacts of methyltransferase transcription patterns on the methylome, we conducted methylome sequencing on samples cultured at pH 7 or pH 5. We found differentially methylated motifs between these growth conditions, and that deletions of arsS and/or hsdM1 interfere with the epigenetic acid response. Deletion of arsS leads to altered activity of HsdM1 and multiple other methyltransferases under both pH conditions indicating that the ArsRS TCS, in addition to direct effects on regulon transcription during acid acclimation, may also indirectly impact gene expression via regulation of the methylome. We determined the target motif of HsdM1 (HP0463) to be the complementary bipartite sequence pair 5’-(HH)TCAm6AVN6TGY-3’ and 3’-AGTN6GAm6ACA-5’. The Type II m5C DNA methyltransferase M.HpyAVIII (HP1121) is regulated by ArsS and HsdM1. This complex regulation of DNA methyltransferases, and thus differential methylation patterns, may have implications for the decades-long persistent infection by H. pylori. This study expands the possibilities for complex, epigenomic regulation in Helicobacter pylori. We demonstrate that the H. pylori methylome is plastic and acid-sensitive via the two-component system ArsRS and the DNA methyltransferase HsdM1. The control of a methyltransferase by ArsRS may allow for a layered response to changing acidity. Likely, an early response whereby ArsR∼P affects regulon expression, including the methyltransferase hsdM1. Then, a somewhat later effect as the altered methylome, due to altered HsdM1 expression, subsequently alters the expression of other genes involved in acclimation. The intermediate methylation of certain motifs supports the hypothesis that methyltransferases play a regulatory role. Untangling this additional web of regulation could play a key role in understanding H. pylori colonization and persistence.