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Quantifying sector‐resolved methane fluxes in complex emissions environments is challenging yet necessary to improve emissions inventories and guide policy. Here, we separate energy and agriculture sector emissions using a dynamic linear model analysis of methane, ethane, and ammonia data measured at a Northern Colorado site from November 2021 to January 2022. By combining these sector‐apportioned observations with spatially resolved inventories and Bayesian inverse methods, energy and agriculture methane fluxes are optimized across the study's ∼850 km2 sensitivity area. Energy sector fluxes are synthesized with previous literature to evaluate trends in energy sector methane emissions. Optimized agriculture fluxes in the study area were 3.5× larger than inventory estimates; we demonstrate this discrepancy is consistent with differences in the modeled versus real‐world spatial distribution of agricultural sources. These results highlight how sector‐apportioned methane observations can yield multi‐sector inventory optimizations in complex environments. Plain Language Summary Improving our knowledge of the locations, magnitudes, and types of methane sources is important for implementing effective emissions mitigation technologies and regulations. Methane emissions are often challenging to quantify because a wide variety of sources can emit methane, and these disparate sources are often intermingled. We demonstrate how a dynamic linear model can use multi‐month time series of two tracer gases, ethane and ammonia, to effectively separate methane emissions from the energy and agriculture sectors. Incorporating these data into a Bayesian inverse analysis refines the magnitude and distribution of methane fluxes from each sector. Our analysis reveals that methane from agriculture is several times higher than inventory estimates. While this is in part due to the spatial distribution of sources, more monitoring is needed to improve agriculture emissions factors. Energy sector emissions factors optimized in this work are consistent with other regional studies of energy sector methane emissions. A synthesis of these works demonstrates a regional decline in energy sector emissions despite a concomitant increase in oil and gas extraction; however, current emissions are similar to 2008 estimates. Key Points A dynamic linear model apportions energy and agriculture methane emissions from multi‐month trace gas measurements in Northern Colorado An estimated 0.4 ± 0.2 kg CH4 are emitted per barrel of oil equivalent produced, yielding a Wattenberg Field emission rate of 15 Mg CH4/hr Optimized agriculture methane emissions are higher than inventory predictions, in part due to mislocated fluxes in the inventory

Optical frequency combs have revolutionized optical frequency metrology and are being actively investigated in a number of applications outside of pure optical frequency metrology. For reasons of cost, robustness, performance, and flexibility, the erbium fiber laser frequency comb has emerged as the most commonly used frequency comb system and many different designs of erbium fiber frequency combs have been demonstrated. We review the different approaches taken in the design of erbium fiber frequency combs, including the major building blocks of the underlying mode-locked laser, amplifier, supercontinuum generation and actuators for stabilization of the frequency comb.

We present an open-path mid-infrared dual-comb spectroscopy (DCS) system capable of precise measurement of the stable water isotopologues H216O and HD16O. This system ran in a remote configuration at a rural test site for 3.75 months with 60 % uptime and achieved a precision of < 2 ‰ on the normalized ratio of H216O and HD16O (δD) in 1000 s. Here, we compare the δD values from the DCS system to those from the National Ecological Observatory Network (NEON) isotopologue point sensor network. Over the multi-month campaign, the mean difference between the DCS δD values and the NEON δD values from a similar ecosystem is < 2 ‰ with a standard deviation of 18 ‰, which demonstrates the inherent accuracy of DCS measurements over a variety of atmospheric conditions. We observe time-varying diurnal profiles and seasonal trends that are mostly correlated between the sites on daily timescales. This observation motivates the development of denser ecological monitoring networks aimed at understanding regional- and synoptic-scale water transport. Precise and accurate open-path measurements using DCS provide new capabilities for such networks.

Accurate whole-farm or herd-level measurements of livestock methane emissions are necessary for anthropogenic greenhouse gas inventories and to evaluate mitigation strategies. A controlled methane (CH4) release experiment was performed to determine if dual-comb spectroscopy (DCS) can detect CH4 concentration enhancements produced by a typical herd of beef cattle in an extensive grazing system. Open-path DCS was used to measure downwind and upwind CH4 concentrations from 10 point sources of methane simulating cattle emissions. The CH4 mole fractions and wind velocity data were used to calculate CH4 flux using an inverse dispersion model, and the simulated fluxes were then compared to the actual CH4 release rate. For a source located 60 m from the downwind path, the DCS system detected 10 nmol mol−1 CH4 horizontal concentration gradient above the atmospheric background concentration with a precision of 6 nmol mol−1 in 15 min interval. A CH4 release of 3970 g d−1 was performed, resulting in an average concentration enhancement of 24 nmol mol−1 of CH4. The calculated CH4 flux was 4002 g d−1, showing good agreement with the actual CH4 release rate. Periodically altering the downwind path, which may be needed to track moving cattle, did not adversely affect the ability of the instruments to determine the CH4 flux. These results give us confidence that CH4 flux can be determined by grazing cattle with low disturbance and direct field-scale measurements.

The Contaminant Repository for Affinity Purification (CRAPome) is a database of annotated negative control-data that can be used for filtering out nonspecific interactions in affinity purification-mass spectrometry experiments. Affinity purification coupled with mass spectrometry (AP-MS) is a widely used approach for the identification of protein-protein interactions. However, for any given protein of interest, determining which of the identified polypeptides represent bona fide interactors versus those that are background contaminants (for example, proteins that interact with the solid-phase support, affinity reagent or epitope tag) is a challenging task. The standard approach is to identify nonspecific interactions using one or more negative-control purifications, but many small-scale AP-MS studies do not capture a complete, accurate background protein set when available controls are limited. Fortunately, negative controls are largely bait independent. Hence, aggregating negative controls from multiple AP-MS studies can increase coverage and improve the characterization of background associated with a given experimental protocol. Here we present the contaminant repository for affinity purification (the CRAPome) and describe its use for scoring protein-protein interactions. The repository (currently available for Homo sapiens and Saccharomyces cerevisiae ) and computational tools are freely accessible at http://www.crapome.org/ .

The origin of methylmercury in pelagic fish remains unclear, with many unanswered questions regarding the production and degradation of this neurotoxin in the water column. We used mercury (Hg) stable isotope ratios of marine particles and biota to elucidate the cycling of methylmercury prior to incorporation into the marine food web. The Hg isotopic composition of particles, zooplankton, and fish reveals preferential methylation of Hg within small (< 53 μm) marine particles in the upper 400 m of the North Pacific Ocean. Mass-dependent Hg isotope ratios (δ202Hg) recorded in small particles overlap with previously estimated δ202Hg values for methylmercury sources to Pacific and Atlantic Ocean food webs. Particulate compound specific isotope analysis of amino acids (CSIA-AA) yield δ15N values that indicate more-significant microbial decomposition in small particles compared to larger particles. CSIA-AA and Hg isotope data also suggest that large particles (> 53 μm) collected in the equatorial ocean are distinct from small particles and resemble fecal pellets. Additional evidence for Hg methylation within small particles is provided by a statistical mixing model of even mass–independent (Δ200Hg and Δ204Hg) isotope values, which demonstrates that Hg within near-surface marine organisms (0–150 m) originates from a combination of rainfall and marine particles. In contrast, in meso- and upper bathypelagic organisms (200–1,400 m), the majority of Hg originates from marine particles with little input from wet deposition. The occurrence of methylation within marine particles is supported further by a correlation between Δ200Hg and Δ199Hg values, demonstrating greater overlap in the Hg isotopic composition of marine organisms with marine particles than with total gaseous Hg or wet deposition.

Proteins that respond to DNA damage play critical roles in normal and diseased states in human biology. Studies have suggested that the S. cerevisiae protein CMR1/YDL156w is associated with histones and is possibly associated with DNA repair and replication processes. Through a quantitative proteomic analysis of affinity purifications here we show that the human homologue of this protein, WDR76, shares multiple protein associations with the histones H2A, H2B, and H4. Furthermore, our quantitative proteomic analysis of WDR76 associated proteins demonstrated links to proteins in the DNA damage response like PARP1 and XRCC5 and heterochromatin related proteins like CBX1, CBX3, and CBX5. Co-immunoprecipitation studies validated these interactions. Next, quantitative imaging studies demonstrated that WDR76 was recruited to laser induced DNA damage immediately after induction, and we compared the recruitment of WDR76 to laser induced DNA damage to known DNA damage proteins like PARP1, XRCC5, and RPA1. In addition, WDR76 co-localizes to puncta with the heterochromatin proteins CBX1 and CBX5, which are also recruited to DNA damage but much less intensely than WDR76. This work demonstrates the chromatin and DNA damage protein associations of WDR76 and demonstrates the rapid response of WDR76 to laser induced DNA damage.

INTRODUCTION Alzheimer's disease (AD) is the leading cause of death in individuals with Down syndrome (DS). Participation in moderate‐to‐vigorous physical activity (MVPA) may prevent or delay the onset of AD. Therefore, we evaluated the potential effectiveness of a remotely delivered home‐based group exercise (≈8/group) to increase daily MVPA and cardiorespiratory fitness in adults with DS to a level that may be associated with delaying AD in adults with DS. METHODS Adults with DS (n = 81, age ≈27 years 55% female) without dementia were randomized (2:2:1) to a 12‐month intervention, which included 40‐min exercise sessions scheduled once (remote low (RL), n = 32) or 3 times per week (remote high (RH), n = 34) plus twice monthly 20‐min individual remotely delivered support/education sessions or to a control arm who attended twice monthly support/education sessions only (SE, n = 15). MVPA (minutes/day) was assessed by accelerometer, and cardiorespiratory fitness (VO2 Peak, mL/kg/min) was assessed using a maximal treadmill test RESULTS Participant retention at 12 months was 100%. Attendance at exercise and support/education sessions averaged ~85% and ~86%, respectively. Linear mixed modeling revealed no significant differences in change in MVPA from baseline to 12 months between the RH (10 min/day) and the RL arms (2 min/day, p = 0.06) or the RH and SE arms (1 min/day p = 0.13). The change in VO₂ Peak differed significantly between the RH (2.0 ± 4.6 mL/kg/min) and RL arms (−1.1 ± 3.0 mL/kg/min, p = 0.04) but not between the RH and SE arms (1.2 ± 5.3 mL/kg/min, p = 0.85). DISCUSSION Our results suggest that remotely delivered group exercise (3 times/week) in conjunction with twice‐monthly support/education is feasible and may increase daily MVPA and cardiorespiratory fitness to a level that may be associated with improvements in health and cognitive parameters in adults with DS. CLINICAL TRIALS REGISTRATION This trial was approved by the Institutional Review Board at the University of Kansas Medical Center and was registered on clinicaltrials.gov (NCT04048759). Highlights Evidence suggests that exercise may delay Alzheimer's disease (AD) in the general population, but its impact on adults with Down syndrome (DS) remains unknown. Adults attended remote exercise sessions either 1 or 3 times a week or received basic education about exercise. Those who attend exercise sessions 3 times a week increased their physical activity by 70 min per week. Those who attend exercise sessions 3 times a week improve their cardiorespiratory fitness. Remote exercise can be used in future AD prevention trials in adults with DS.

Objectives. We assessed the effectiveness of a 5-year trial of a comprehensive school-based program designed to prevent substance use, violent behaviors, and sexual activity among elementary-school students. Methods. We used a matched-pair, cluster-randomized, controlled design, with 10 intervention schools and 10 control schools. Fifth-graders (N = 1714) self-reported on lifetime substance use, violence, and voluntary sexual activity. Teachers of participant students reported on student (N = 1225) substance use and violence. Results. Two-level random-effects count models (with students nested within schools) indicated that student-reported substance use (rate ratio [RR] = 0.41; 90% confidence interval [CI] = 0.25, 0.66) and violence (RR = 0.42; 90% CI = 0.24, 0.73) were significantly lower for students attending intervention schools. A 2-level random-effects binary model indicated that sexual activity was lower (odds ratio = 0.24; 90% CI = 0.08, 0.66) for intervention students. Teacher reports substantiated the effects seen for student-reported data. Dose-response analyses indicated that students exposed to the program for at least 3 years had significantly lower rates of all negative behaviors. Conclusions. Risk-related behaviors were substantially reduced for students who participated in the program, providing evidence that a comprehensive school-based program can have a strong beneficial effect on student behavior.

Background Evidence in adults without Down syndrome (DS) suggests that exercise during mid‐life improves cognitive function and decreases risk of later life dementia. Studies supporting this relationship in adults with DS are limited. The purpose of this study was to examine changes in cognitive function after a 12‐mo exercise intervention in adults with DS without dementia. Method Adults with DS were randomized (2:2:1) to one of three exercise interventions: remotely delivered group exercise sessions conducted 1x/wk. (RL), remotely delivered group exercise sessions conducted 3x/wk. (RH), or a usual care control (UC) which did not receive the remotely delivered sessions. All groups received an activity tracker, access to resources for increasing exercise, and twice monthly 20‐min remotely delivered individual support/education sessions. Physical activity (accelerometry) was assessed across 12 mos. Cognitive function was assessed at baseline, 6, and 12 months, using the CANTAB® DS Battery, which included tests measuring multitasking, episodic memory, and reaction time. Linear mixed‐effects analyses were used to test the effect of the intervention on changes in cognitive function, controlling for age, sex, and level of intellectual disability Result Eighty‐one adults with DS (age ∼27yrs., ∼55% female, ∼24% minorities) were randomized to the RH (n = 34), RL (n = 32) or UC (n = 15) groups. Study retention was 100% and study adherence to the remote exercise sessions was 90% in the RH arm and 79% in the RL arm. MVPA increased by 10.6 min/day and 1.4 mins/day in the RH and UC arms, respectively, but decreased by ‐3.2 mins/day in the RL arm. Across all groups episodic memory (p = 0.018), 5‐choice movement time (p = 0.017), and 5‐choice reaction time (p = 0.022) improved across the intervention, however, there were no significant group or group x time effects. Conclusion In adults with DS, participation in a 12‐month exercise intervention led to improvements in episodic memory and reaction time regardless of intervention arm. Future adequately powered trials are warranted to examine the impact of long‐term exercise on cognition function outcomes compared to a non‐exercise control.