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OBJECTIVE: To test effectiveness of the LEAP (Learn Engage Act Process) Program on engaging frontline Veteran Health Administration (VHA) medical center teams in continuous quality improvement (QI), a core capability for learning health systems. DATA SOURCES AND STUDY SETTING: Data sources included VHA electronic health record (EHR) data, surveys, and LEAP coaching field notes. STUDY DESIGN: A staggered difference-in-differences study was conducted. Fifty-five facilities participated in LEAP across eight randomly assigned clusters of 6-8 facilities per cluster over 2 years. Non-participating facilities were used as controls. A MOVE! weight management program team completed a Plan-Do-Study-Act cycle of change supported by learning curriculum, coaching, and virtual collaboratives in LEAP facilities. Primary outcome was program reach to Veterans. A mixed-effects model compared pre- versus post-LEAP periods for LEAP versus control facilities. LEAP adherence, satisfaction, and cost to deliver LEAP were evaluated. DATA COLLECTION/EXTRACTION METHODS: Thirty months of facility-level EHR MOVE! enrollment data were included in analyses. LEAP Satisfaction and QI skills were elicited via surveys at baseline and 6-month post-LEAP. PRINCIPAL FINDINGS: Fifty-five facilities were randomly assigned to eight time-period-based clusters to receive LEAP (71% completed LEAP) and 82 non-participating facilities were randomly assigned as controls. Reach in LEAP and control facilities was comparable in the 12-month pre-LEAP period (p = 0.07). Though LEAP facilities experienced slower decline in reach in the 12-month post-LEAP period compared with controls (p < 0.001), this is likely due to unexplained fluctuations in controls. For LEAP facilities, satisfaction was high (all mean ratings >4 on a 5-point scale), self-reported use of QI methods increased significantly (p-values <0.05) 6 months post-LEAP, and delivery cost was $4024 per facility-based team. CONCLUSION: Control facilities experienced declining reach in the 12-month post-LEAP period, but LEAP facilities did not, plus they reported higher engagement in QI, an essential capability for learning health systems.
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The biosynthetic secretory pathway is comprised of multiple steps, modifications and interactions that form a highly precise pathway of protein trafficking and secretion, that is essential for eukaryotic life. The general outline of this pathway is understood, however the specific mechanisms are still unclear. In the last 15 years there have been vast advancements in technology that enable us to advance our understanding of this complex and subtle pathway. Therefore, based on the strong foundation of work performed over the last 40 years, we can now build another level of understanding, using the new technologies available. The biosynthetic secretory pathway is a high precision process, that involves a number of tightly regulated steps: Protein folding and quality control, cargo selection for Endoplasmic Reticulum (ER) exit, Golgi trafficking, sorting and secretion. When deregulated it causes severe diseases that here we categorise into three main groups of aberrant secretion: decreased, excess and altered secretion. Each of these categories disrupts organ homeostasis differently, effecting extracellular matrix composition, changing signalling events, or damaging the secretory cells due to aberrant intracellular accumulation of secretory proteins. Diseases of aberrant secretion are very common, but despite this, there are few effective therapies. Here we describe ER exit sites (ERES) as key hubs for regulation of the secretory pathway, protein quality control and an integratory hub for signalling within the cell. This review also describes the challenges that will be faced in developing effective therapies, due to the specificity required of potential drug candidates and the crucial need to respect the fine equilibrium of the pathway. The development of novel tools is moving forward, and we can also use these tools to build our understanding of the acute regulation of ERES and protein trafficking. Here we review ERES regulation in context as a therapeutic strategy.
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The Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) field campaign provides accurate data for aerosol characterization and trace gas profiles, and establishes knowledge of the relationships between aerosols and water. The dropsonde dataset provides an in situ characterization of the vertical thermodynamic structure of the atmosphere during 165 research flights by NASA Langley's King Air research aircraft between February 2020 and June 2022 and four test flights between December 2019 and November 2021. The research flights covered the western North Atlantic region, off the coast of the Eastern United States and around Bermuda and covered all seasons. The dropsonde profiles provide observations of temperature, pressure, relative humidity, and horizontal and vertical winds between the surface and about 9 km. 801 dropsondes were released, of which 796 were processed and 788 provide complete profiles of all parameters between the flight level and the surface with normal parachute performance. Here, we describe the dataset, the processing of the measurements, general statistics, and applications of this rich dataset.
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In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates.
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INTRODUCTION: Sciatica is a common condition and is associated with higher levels of pain, disability, poorer quality of life, and increased use of health resources compared with low back pain alone. Although many patients recover, a third develop persistent sciatica symptoms. It remains unclear, why some patients develop persistent sciatica as none of the traditionally considered clinical parameters (eg, symptom severity, routine MRI) are consistent prognostic factors.The FORECAST study (factors predicting the transition from acute to persistent pain in people with 'sciatica') will take a different approach by exploring mechanism-based subgroups in patients with sciatica and investigate whether a mechanism-based approach can identify factors that predict pain persistence in patients with sciatica. METHODS AND ANALYSIS: We will perform a prospective longitudinal cohort study including 180 people with acute/subacute sciatica. N=168 healthy participants will provide normative data. A detailed set of variables will be assessed within 3 months after sciatica onset. This will include self-reported sensory and psychosocial profiles, quantitative sensory testing, blood inflammatory markers and advanced neuroimaging. We will determine outcome with the Sciatica Bothersomeness Index and a Numerical Pain Rating Scale for leg pain severity at 3 and 12 months.We will use principal component analysis followed by clustering methods to identify subgroups. Univariate associations and machine learning methods optimised for high dimensional small data sets will be used to identify the most powerful predictors and model selection/accuracy.The results will provide crucial information about the pathophysiological drivers of sciatica symptoms and may identify prognostic factors of pain persistence. ETHICS AND DISSEMINATION: The FORECAST study has received ethical approval (South Central Oxford C, 18/SC/0263). The dissemination strategy will be guided by our patient and public engagement activities and will include peer-reviewed publications, conference presentations, social media and podcasts. TRIAL REGISTRATION NUMBER: ISRCTN18170726; Pre-results.
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Dor Lombar , Ciática , Humanos , Estudos de Coortes , Estudos Longitudinais , Prognóstico , Estudos Prospectivos , Qualidade de Vida , Ciática/diagnósticoRESUMO
BACKGROUND: The Consolidated Framework for Implementation Research (CFIR) is a determinant framework that can be used to guide context assessment prior to implementing change. Though a few quantitative measurement instruments have been developed based on the CFIR, most assessments using the CFIR have relied on qualitative methods. One challenge to measurement is to translate conceptual constructs which are often described using highly abstract, technical language into lay language that is clear, concise, and meaningful. The purpose of this paper is to document methods to develop a freely available pragmatic context assessment tool (pCAT). The pCAT is based on the CFIR and designed for frontline quality improvement teams as an abbreviated assessment of local facilitators and barriers in a clinical setting. METHODS: Twenty-seven interviews using the Think Aloud method (asking participants to verbalize thoughts as they respond to assessment questions) were conducted with frontline employees to improve a pilot version of the pCAT. Interviews were recorded and transcribed verbatim; the CFIR guided coding and analyses. RESULTS: Participants identified several areas where language in the pCAT needed to be modified, clarified, or allow more nuance to increase usefulness for frontline employees. Participants found it easier to respond to questions when they had a recent, specific project in mind. Potential barriers and facilitators tend to be unique to each specific improvement. Participants also identified missing concepts or that were conflated, leading to refinements that made the pCAT more understandable, accurate, and useful. CONCLUSIONS: The pCAT is designed to be practical, using everyday language familiar to frontline employees. The pCAT is short (14 items), freely available, does not require research expertise or experience. It is designed to draw on the knowledge of individuals most familiar with their own clinical context. The pCAT has been available online for approximately two years and has generated a relatively high level of interest indicating potential usefulness of the tool.
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BACKGROUND: Perinatal and childhood postmortem imaging has been accepted as a noninvasive alternative or adjunct to autopsy. However, the variation in funding models from institution to institution is a major factor prohibiting uniform provision of this service. OBJECTIVE: To describe current funding models employed in European and non-European institutions offering paediatric postmortem imaging services and to discuss the perceived barriers to future postmortem imaging service provision. MATERIALS AND METHODS: A web-based 16-question survey was distributed to members of the European Society of Paediatric Radiology (ESPR) and ESPR postmortem imaging task force over a 6-month period (March-August 2021). Survey questions related to the radiologic and autopsy services being offered and how each was funded within the respondent's institute. RESULTS: Eighteen individual responses were received (13/18, 72.2% from Europe). Only one-third of the institutions (6/18, 33.3%) have fully funded postmortem imaging services, with the remainder receiving partial (6/18, 33.3%) or no funding (5/18, 27.8%). Funding (full or partial) was more commonly available for forensic work (13/18, 72%), particularly where this was nationally provided. Where funding was not provided, the imaging and reporting costs were absorbed by the institute. CONCLUSION: Increased access is required for the expansion of postmortem imaging into routine clinical use. This can only be achieved with formal funding on a national level, potentially through health care commissioning and acknowledgement by health care policy makers and pathology services of the value the service provides following the death of a fetus or child. Funding should include the costs involved in training, equipment, reporting and image acquisition.
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Diagnóstico por Imagem , Radiologia , Gravidez , Feminino , Criança , Humanos , Autopsia/métodos , Diagnóstico por Imagem/métodos , Medicina Legal , Inquéritos e QuestionáriosRESUMO
Combined lidar and polarimeter retrievals of aerosol, cloud, and ocean microphysical properties involve single-scattering cloud calculations that are time consuming. We create a look-up table to speed up these calculations for water droplets in the atmosphere. In our new Lorenz-Mie look-up table we tabulate the light scattering by an ensemble of homogeneous isotropic spheres at wavelengths starting from 0.35 µm. The look-up table covers liquid water cloud particles with radii in the range of 0.001-500 µm while gaining an increase of up to 104 in computational speed. The covered complex refractive indices range from 1.25 to 1.36 for the real part and from 0 to 0.001 for the imaginary part. We show that we can precisely compute inherent optical properties for the particle size distributions ranging up to 100 µm for the effective radius and up to 0.6 for the effective variance. We test wavelengths from 0.35 to 2.3 µm and find that the elements of the normalized scattering matrix as well as the asymmetry parameter, the absorption, backscatter, extinction, and scattering coefficients are precise to within 1% for 96.7%-100% of cases depending on the inherent optical property. We also provide an example of using the look-up table with in situ measurements to determine agreement with remote sensing. The table together with C++, Fortran, MATLAB, and Python codes to interpolate the complex refractive index and apply different particle size distributions are freely available online.
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Background: The Veterans Health Administration (VHA) is the largest integrated health system in the U.S. and has identified the learning health system as a strategic priority. Clinicians and staff engaging in active learning through continuous quality improvement (QI) is a key pillar for learning system maturity. An interdisciplinary frontline team at a VHA medical center participated in the Learn. Engage. Act. Process. (LEAP) virtual coaching program to learn how to conduct multidisciplinary team-based QI cycles of change. These clinicians lead and deliver the MOVE! weight management program, an evidence-based comprehensive lifestyle intervention. The team worked to continuously improve patient weight loss by engaging in incremental learning cycles of change. The aim of this study is to tell the story of this team's learning experience and the resulting positive reinforcing loop with patient outcomes. Methods: This is a mixed methods case study description of one team that participated in the LEAP Program that provides hands-on QI learning for frontline teams with virtual coaching and a structured curriculum. Autoethnographic qualitative descriptions of team experiences over time illustrate this team's continued engagement in learning loops. Multilevel linear modeling was used to assess patient outcomes before vs after the team's participation in LEAP. Results: The team's participation in LEAP provided a set of fundamental QI skills and established a commitment to continual learning. Incremental improvements led to significant weight loss for patients who participated in MOVE! after the team completed LEAP (mean = 9.80 pounds; SD 10.43) compared to the pre-LEAP time period (mean = -6.83 pounds; SD 9.63). Conclusions: Despite competing priorities and time limitations, this team's experiences provide a positive vision of how team engagement in data-driven continuous learning is feasible at the frontline and can lead to higher job satisfaction and stronger teams. These types of team activities provide much-needed backbone to being a mature learning health system.
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Clear cell renal cell carcinoma (ccRCC) is the most common form of kidney cancer. Despite therapeutic advances, long term survival in patients diagnosed with advanced disease is low. Efforts to understand the mechanisms promoting disease progression will likely produce novel therapeutic targets. The unfolded protein response (UPR) is activated when unfolded protein accumulates in the endoplasmic reticulum (ER) upon cellular stress. Constitutive UPR activation is a characteristic of many malignancies. We discuss the accumulating evidence that describes a role for the UPR in ccRCC. Studies focused on UPR signalling may provide compelling avenues for therapeutic intervention in the future.
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Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Estresse do Retículo Endoplasmático/fisiologia , Oxigênio , Resposta a Proteínas não Dobradas , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Carcinogênese , Transformação Celular Neoplásica , Resistência a MedicamentosRESUMO
IRE1α is constitutively active in several cancers and can contribute to cancer progression. Activated IRE1α cleaves XBP1 mRNA, a key step in production of the transcription factor XBP1s. In addition, IRE1α cleaves select mRNAs through regulated IRE1α-dependent decay (RIDD). Accumulating evidence implicates IRE1α in the regulation of lipid metabolism. However, the roles of XBP1s and RIDD in this process remain ill-defined. In this study, transcriptome and lipidome profiling of triple negative breast cancer cells subjected to pharmacological inhibition of IRE1α reveals changes in lipid metabolism genes associated with accumulation of triacylglycerols (TAGs). We identify DGAT2 mRNA, encoding the rate-limiting enzyme in TAG biosynthesis, as a RIDD target. Inhibition of IRE1α, leads to DGAT2-dependent accumulation of TAGs in lipid droplets and sensitizes cells to nutritional stress, which is rescued by treatment with the DGAT2 inhibitor PF-06424439. Our results highlight the importance of IRE1α RIDD activity in reprograming cellular lipid metabolism.
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Endorribonucleases , Metabolismo dos Lipídeos , Neoplasias , Proteínas Serina-Treonina Quinases , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Endorribonucleases/metabolismo , Humanos , Metabolismo dos Lipídeos/genética , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismoRESUMO
BACKGROUND: The adoption and sustainment of evidence-based practices (EBPs) is a challenge within many healthcare systems, especially in settings that have already strived but failed to achieve longer-term goals. The Veterans Affairs (VA) Maintaining Implementation through Dynamic Adaptations (MIDAS) Quality Enhancement Research Initiative (QUERI) program was funded as a series of trials to test multi-component implementation strategies to sustain optimal use of three EBPs: (1) a deprescribing approach intended to reduce potentially inappropriate polypharmacy; (2) appropriate dosing and drug selection of direct oral anticoagulants (DOACs); and (3) use of cognitive behavioral therapy as first-line treatment for insomnia before pharmacologic treatment. We describe the design and methods for a harmonized series of cluster-randomized control trials comparing two implementation strategies. METHODS: For each trial, we will recruit 8-12 clinics (24-36 total). All will have access to relevant clinical data to identify patients who may benefit from the target EBP at that clinic and provider. For each trial, clinics will be randomized to one of two implementation strategies to improve the use of the EBPs: (1) individual-level academic detailing (AD) or (2) AD plus the team-based Learn. Engage. Act. PROCESS: (LEAP) quality improvement (QI) learning program. The primary outcomes will be operationalized across the three trials as a patient-level dichotomous response (yes/no) indicating patients with potentially inappropriate medications (PIMs) among those who may benefit from the EBP. This outcome will be computed using month-by-month administrative data. Primary comparison between the two implementation strategies will be analyzed using generalized estimating equations (GEE) with clinic-level monthly (13 to 36 months) percent of PIMs as the dependent variable. Primary comparative endpoint will be at 18 months post-baseline. Each trial will also be analyzed independently. DISCUSSION: MIDAS QUERI trials will focus on fostering sustained use of EBPs that previously had targeted but incomplete implementation. Our implementation approaches are designed to engage frontline clinicians in a dynamic optimization process that integrates the use of actional clinical data and making incremental changes, designed to be feasible within busy clinical settings. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05065502 . Registered October 4, 2021-retrospectively registered.
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OBJECTIVE: Support for chronic conditions such as diabetes from friends and family positively influences health management and outcomes, but limited data exist on how and why caregivers assume specific support roles for otherwise independent aging adults. We conducted a qualitative study to examine the nature of caregivers' roles in supporting Veterans' management of a chronic condition and caregivers' reasons for assuming those roles, using Type 2 diabetes as an example. METHODS: Thirty-two interviews were conducted with Veterans with Type 2 diabetes (n = 20) and their caregivers (n = 12). Two coders independently analyzed interview transcripts using a thematic analysis approach. RESULTS: Three central roles of caregivers in diabetes management were described: direct care support, memory support/care organizer, and advocate. Three explanations for assuming caregiving roles emerged: changes in patient health, natural evolution of family roles, and caregivers' health care experience or training. DISCUSSION: Understanding what roles caregivers fill and why is critical to designing services to support caregivers in helping improve chronic health condition management for aging adults.
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Diabetes Mellitus Tipo 2 , Veteranos , Adulto , Cuidadores , Doença Crônica , Diabetes Mellitus Tipo 2/terapia , Humanos , Pesquisa QualitativaRESUMO
Ångström exponents (α) allow reconstruction of aerosol optical spectra over a broad range of wavelengths from measurements at two or more wavelengths. Hyperspectral measurements of atmospheric aerosols provide opportunities to probe measured spectra for information inaccessible from only a few wavelengths. Four sets of hyperspectral in situ aerosol optical coefficients (aerosol-phase total extinction, σ ext, and absorption, σ abs; liquid-phase soluble absorption from methanol, σ MeOH-abs, and water, σ DI-abs, extracts) were measured from biomass burning aerosols (BBAs). Hyperspectral single scattering albedo (ω), calculated from σ ext and σ abs, provide spectral resolution over a wide spectral range rare for this optical parameter. Observed spectral shifts between σ abs and σ MeOH-abs/σ DI-abs argue in favor of measuring σ abs rather than reconstructing it from liquid extracts. Logarithmically transformed spectra exhibited curvature better fit by second-order polynomials than linear α. Mapping second order fit coefficients (a 1, a 2) revealed samples from a given fire tended to cluster together, that is, aerosol spectra from a given fire were similar to each other and somewhat distinct from others. Separation in (a 1, a 2) space for spectra with the same α suggest additional information in second-order parameterization absent from the linear fit. Spectral features found in the fit residuals indicate more information in the measured spectra than captured by the fits. Above-detection σ MeOH-abs at 0.7 µm suggests assuming all absorption at long visible wavelengths is BC to partition absorption between BC and brown carbon (BrC) overestimates BC and underestimates BrC across the spectral range. Hyperspectral measurements may eventually discriminate BBA among fires in different ecosystems under variable conditions.
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Aerosol mass extinction efficiency (MEE) is a key aerosol property used to connect aerosol optical properties with aerosol mass concentrations. Using measurements of smoke obtained during the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign we find that mid-visible smoke MEE can change by a factor of 2-3 between fresh smoke (<2 hr old) and one-day-old smoke. While increases in aerosol size partially explain this trend, changes in the real part of the aerosol refractive index (real(n)) are necessary to provide closure assuming Mie theory. Real(n) estimates derived from multiple days of FIREX-AQ measurements increase with age (from 1.40 - 1.45 to 1.5-1.54 from fresh to one-day-old) and are found to be positively correlated with organic aerosol oxidation state and aerosol size, and negatively correlated with smoke volatility. Future laboratory, field, and modeling studies should focus on better understanding and parameterizing these relationships to fully represent smoke aging.
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Introduction. Detailed or "full" shared decision making (SDM) about cancer screening is difficult in the primary care setting. Time spent discussing cancer screening is time not spent on other important issues. Given time constraints, brief SDM that is incomplete but addresses key elements may be feasible and acceptable. However, little is known about how patients feel about abbreviated SDM. This study assessed patient perspectives on a compromise solution ("everyday SDM"): 1) primary care provided makes a tailored recommendation, 2) briefly presents qualitative information on key tradeoffs, and 3) conveys full support for decisional autonomy and desires for more information. Methods. We recruited a stratified random sample of Veterans from an academic Veterans Affairs medical center who were eligible for lung cancer screening, oversampling women and minority patients, to attend a 6-hour deliberative focus group. Experts informed participants about cancer screening, factors that influence screening benefits, and the role of patient preferences. Then, facilitator-led small groups elicited patient questions and informed opinions about the everyday SDM proposal, its acceptability, and their recommendations for improvement. Results. Thirty-six Veterans with a heavy smoking history participated (50% male, 83% white). There was a strong consensus that everyday SDM was acceptable if patients were the final deciders and could get more information on request. Participants broadly recommended that clinicians only mention downsides directly related to screening and avoid discussion of potential downstream harms (such as biopsies). Discussion. Although further testing in more diverse populations and different conditions is needed, these patients found the everyday SDM approach to be acceptable for routine lung cancer screening discussions, despite its use of an explicit recommendation and presentation of only qualitative information.
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The warm Gulf Stream sea surface temperatures strongly impact the evolution of winter clouds behind atmospheric cold fronts. Such cloud evolution remains challenging to model. The Gulf Stream is too wide within the ERA5 and MERRA2 reanalyses, affecting the turbulent surface fluxes. Known problems within the ERA5 boundary layer (too-dry and too-cool with too strong westerlies), ascertained primarily from ACTIVATE 2020 campaign aircraft dropsondes and secondarily from older buoy measurements, reinforce surface flux biases. In contrast, MERRA2 winter surface winds and air-sea temperature/humidity differences are slightly too weak, producing surface fluxes that are too low. Reanalyses boundary layer heights in the strongly forced winter cold-air-outbreak regime are realistic, whereas late-summer quiescent stable boundary layers are too shallow. Nevertheless, the reanalysis biases are small, and reanalyses adequately support their use for initializing higher-resolution cloud process modeling studies of cold-air outbreaks.
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Cancer cells bearing distinct KRAS mutations exhibit variable sensitivity to SHP2 inhibitors (SHP2i). Here we show that cells harboring KRAS Q61H are uniquely resistant to SHP2i, and investigate the underlying mechanisms using biophysics, molecular dynamics, and cell-based approaches. Q61H mutation impairs intrinsic and GAP-mediated GTP hydrolysis, and impedes activation by SOS1, but does not alter tyrosyl phosphorylation. Wild-type and Q61H-mutant KRAS are both phosphorylated by Src on Tyr32 and Tyr64 and dephosphorylated by SHP2, however, SHP2i does not reduce ERK phosphorylation in KRAS Q61H cells. Phosphorylation of wild-type and Gly12-mutant KRAS, which are associated with sensitivity to SHP2i, confers resistance to regulation by GAP and GEF activities and impairs binding to RAF, whereas the near-complete GAP/GEF-resistance of KRAS Q61H remains unaltered, and high-affinity RAF interaction is retained. SHP2 can stimulate KRAS signaling by modulating GEF/GAP activities and dephosphorylating KRAS, processes that fail to regulate signaling of the Q61H mutant.