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1.
J Clin Immunol ; 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34973142

RESUMEN

PURPOSE: Our understanding of inborn errors of immunity is increasing; however, their contribution to pediatric sepsis is unknown. METHODS: We used whole-exome sequencing (WES) to characterize variants in genes related to monogenic immunologic disorders in 330 children admitted to intensive care for severe sepsis. We defined candidate variants as rare variants classified as pathogenic or potentially pathogenic in QIAGEN's Human Gene Mutation Database or novel null variants in a disease-consistent inheritance pattern. We investigated variant correlation with infection and inflammatory phenotype. RESULTS: More than one in two children overall and three of four African American children had immunodeficiency-associated variants. Children with variants had increased odds of isolating a blood or urinary pathogen (blood: OR 2.82, 95% CI: 1.12-7.10, p = 0.023, urine: OR: 8.23, 95% CI: 1.06-64.11, p = 0.016) and demonstrating increased inflammation with hyperferritinemia (ferritin [Formula: see text] ng/mL, OR: 2.16, 95% CI: 1.28-3.66, p = 0.004), lymphopenia (lymphocyte count < 1000/µL, OR: 1.66, 95% CI: 1.06 - 2.60, p = 0.027), thrombocytopenia (platelet count < 150,000/µL, OR: 1.76, 95% CI: 1.12-2.76, p = 0.013), and CRP greater than 10 mg/dl (OR: 1.71, 95% CI: 1.10-2.68, p = 0.017). They also had increased odds of requiring extracorporeal membrane oxygenation (ECMO, OR: 4.19, 95% CI: 1.21-14.5, p = 0.019). CONCLUSION: Herein, we describe the genetic findings in this severe pediatric sepsis cohort and their microbiologic and immunologic significance, providing evidence for the phenotypic effect of these variants and rationale for screening children with life-threatening infections for potential inborn errors of immunity.

2.
Cochrane Database Syst Rev ; 12: CD014953, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34931701

RESUMEN

BACKGROUND: Cataract surgery is the most common incisional surgical procedure in ophthalmology and is important in ophthalmic graduate medical education. Although most ophthalmology training programs in the United States (US) include virtual reality (VR) training for cataract surgery, comprehensive reviews that detail the impact of VR training on ophthalmology trainee performance are lacking. OBJECTIVES: To assess the impact of VR training for cataract surgery on the operating performance of postgraduate ophthalmology trainees, measured by operating time, intraoperative complications, postoperative complications, supervising physician ratings, and VR simulator task ratings. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), Ovid MEDLINE, Embase.com, PubMed, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 14 June 2021. SELECTION CRITERIA: We included randomized controlled trials (RCTs) comparing VR training to any other method of training, including non-VR simulation training (e.g., wet laboratory training), didactics training, or no supplementary training in postgraduate ophthalmology trainees. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. Primary outcomes were operating times in the operating room and intraoperative complications. Secondary outcomes were operating times in simulated settings, simulator task ratings, and supervising physician ratings, either in the operating room or simulated settings. MAIN RESULTS: We included six RCTs with a total of 151 postgraduate ophthalmology trainees ranging from 12 to 60 participants in each study. The included studies varied widely in terms of geography: two in the US, and one study each in China, Germany, India, and Morocco. Three studies compared VR training for phacoemulsification cataract surgery on the Eyesi simulator (VRmagic, Mannheim, Germany) with wet laboratory training and two studies compared VR training with no supplementary training. One study compared trainees who received VR training with those who received conventional training for manual small incision cataract surgery on the HelpMeSee simulator (HelpMeSee, New York, NY). Industry financially supported two studies. All studies had at least three domains judged at high or unclear risks of bias. We did not conduct a meta-analysis due to insufficient data (i.e., lack of precision measurements, or studies reported only P values). All evidence was very low-certainty, meaning that any estimates were unreliable. The evidence for the benefits of VR training for trainees was very uncertain for primary outcomes. VR-trained trainees relative to those without supplementary training had shorter operating times (mean difference [MD] -17 minutes, 95% confidence interval [CI] -21.62 to -12.38; 1 study, n = 12; very low-certainty evidence). Results for operating time were inconsistent when comparing VR and wet laboratory training: one study found that VR relative to wet laboratory training was associated with longer operating times (P = 0.038); the other reported that two training groups had similar operating times (P = 0.14). One study reported that VR-trained trainees relative to those without supplementary training had fewer intraoperative complications (P < 0.001); in another study, VR and conventionally trained trainees had similar intraoperative complication rates (MD -8.31, 95% CI -22.78 to 6.16; 1 study, n = 19; very low-certainty evidence). For secondary outcomes, VR training may have similar impact on trainee performance compared to wet laboratory and greater impact compared to no supplementary training, but the evidence was very uncertain. One study reported VR-trained trainees relative to those without supplementary training had significantly reduced operating time in simulated settings (P = 0.0013). Another study reported that VR-trained relative to wet laboratory-trained trainees had shorter operating times in VR settings (MD -1.40 minutes, 95% CI -1.96 to -0.84; 1 study, n = 60) and similar times in wet laboratory settings (MD 0.16 minutes, 95% CI -0.50 to 0.82; 1 study, n = 60). This study also found the VR-trained trainees had higher VR simulator ratings (MD 5.17, 95% CI 0.61 to 9.73; 1 study, n = 60). Results for supervising physician ratings in the operating room were inconsistent: one study reported that VR- and wet laboratory-trained trainees received similar supervising physician ratings for cataract surgery (P = 0.608); another study reported that VR-trained trainees relative to those without supplementary training were less likely to receive poor ratings by supervising physicians for capsulorhexis construction (RR 0.29, 95% CI 0.15 to 0.57). In wet laboratory settings, VR-trained trainees received similar supervising physician ratings compared with wet laboratory-trained trainees (MD -1.50, 95% CI -6.77 to 3.77; n = 60) and higher supervising physician ratings compared with trainees without supplementary training (P < 0.0001). However, the results for all secondary outcomes should be interpreted with caution because of very low-certainty evidence.  AUTHORS' CONCLUSIONS: Current research suggests that VR training may be more effective than no supplementary training in improving trainee performance in the operating room and simulated settings for postgraduate ophthalmology trainees, but the evidence is uncertain. The evidence comparing VR with conventional or wet laboratory training was less consistent.


Asunto(s)
Extracción de Catarata , Catarata , Oftalmología , Facoemulsificación , Realidad Virtual , Humanos
4.
Sci Rep ; 11(1): 22291, 2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34785727

RESUMEN

Methane, a potent greenhouse gas, is the main component of natural gas. Previous research has identified considerable methane emissions associated with oil and gas production, but estimates of emission trends have been inconsistent, in part due to limited in-situ methane observations spanning multiple years in oil/gas production regions. Here we present a unique analysis of one of the longest-running datasets of in-situ methane observations from an oil/gas production region in Utah's Uinta Basin. The observations indicate Uinta methane emissions approximately halved between 2015 and 2020, along with declining gas production. As a percentage of gas production, however, emissions remained steady over the same years, at ~ 6-8%, among the highest in the U.S. Addressing methane leaks and recovering more of the economically valuable natural gas is critical, as the U.S. seeks to address climate change through aggressive greenhouse emission reductions.

5.
Shock ; 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34628452

RESUMEN

BACKGROUND: Little is known about the epidemiology of and outcomes related to red blood cell (RBC) transfusion in septic children across multiple centers. We performed propensity-adjusted secondary analyses of the Biomarker Phenotyping of Pediatric Sepsis and Multiple Organ Failure (PHENOMS) study to test the hypothesis that early RBC transfusion is associated with fewer organ failure-free days in pediatric severe sepsis. METHODS: 401 children were enrolled in the parent study. Children were excluded from these analyses if they received extracorporeal membrane oxygenation (n = 22) or died (n = 1) before sepsis day 2. Propensity-adjusted analyses compared children who received RBC transfusion on or before sepsis day 2 (early RBC transfusion) with those who did not. Logistic regression was used to model the propensity to receive early RBC transfusion. A weighted cohort was constructed using stabilized inverse probability of treatment weights. Variables in the weighted cohort with absolute standardized differences > 0.15 were added to final multivariable models. RESULTS: 50% of children received at least one RBC transfusion. The majority (68%) of first transfusions were on or before sepsis day 2. Early RBC transfusion was not independently associated with organ failure-free (-0.34 [95%CI: - 2, 1.3] days) or PICU-free days (-0.63 [-2.3, 1.1]), but was associated with the secondary outcome of higher mortality (aOR 2.9 [1.1, 7.9]). CONCLUSIONS: RBC transfusion is common in pediatric severe sepsis and may be associated with adverse outcomes. Future studies are needed to clarify these associations, to understand patient-specific transfusion risks, and to develop more precise transfusion strategies.

6.
BMC Med Res Methodol ; 21(1): 227, 2021 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-34689753

RESUMEN

BACKGROUND: Data harmonization is a powerful method to equilibrate items in measures that evaluate the same underlying construct. There are multiple measures to evaluate dementia related behavioral symptoms. Pre-statistical harmonization of behavioral instruments in dementia research is the first step to develop a statistical crosswalk between measures. Studies that conduct pre-statistical harmonization of behavioral instruments rarely document their methods in a structured, reproducible manner. This is a crucial step which entails careful review, documentation and scrutiny of source data to ensure sufficient comparability between items prior to data pooling. Here, we document the pre-statistical harmonization of items measuring behavioral and psychological symptoms among people with dementia. We provide a box of recommended procedure for future studies. METHODS: We identified behavioral instruments that are used in clinical practice, a national survey, and randomized trials of dementia care interventions. We rigorously reviewed question content and scoring procedures to establish sufficient comparability across items as well as item quality prior to data pooling. Additionally, we standardized coding to Stata-readable format, which allowed us to automate approaches to identify potential cross-study differences in items and low-quality items. To ensure reasonable model fit for statistical co-calibration, we estimated two-parameter logistic Item Response Theory models within each of the eight studies. RESULTS: We identified 59 items from 11 behavioral instruments across the eight datasets. We found considerable cross-study heterogeneity in administration and coding procedures for items that measure the same attribute. Discrepancies existed in terms of directionality and quantification of behavioral symptoms for even seemingly comparable items. We resolved item response heterogeneity, missingness and skewness, conditional dependency prior to estimation of item response theory models for statistical co-calibration. We used several rigorous data transformation procedures to address these issues, including re-coding and truncation. CONCLUSIONS: This study highlights the importance of each aspect involved in the pre-statistical harmonization process of behavioral instruments. We provide guidelines and recommendations for how future research may detect and account for similar issues in pooling behavioral and related instruments.


Asunto(s)
Proyectos de Investigación , Humanos , Encuestas y Cuestionarios
7.
J Cataract Refract Surg ; 47(9): 1240-1241, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34468461
8.
Semin Ophthalmol ; : 1-6, 2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34410880

RESUMEN

PURPOSE: To investigate the characteristics of first-year ophthalmology residents associated with high research productivity in twelve years. METHODS: All first-year ophthalmology residents in the United States (US) in 2009 listed by institutional websites were identified. Publications were obtained from Scopus and Google Scholar, h-indices were calculated, and medical school characteristics such as research productivity, region, rank, and average USMLE Steps 1 and 2 scores were obtained from National Institutes of Health, US Census Bureau, and US News. RESULTS: Data were obtained on 70% (316/453) of residents; most were male, had Doctor of Medicine (MD) degrees, and graduated from medical schools in the US or Canada. Having an additional graduate degree [OR: 3.05, 95% CI: 1.07-8.67], between 1 and 3 publications [OR: 4.16, 95% CI: 2.22-7.79], or 4 or more publications [OR: 14.27, 95% CI: 3.13-64.94] were associated with higher future research productivity. CONCLUSION: Graduate degrees and publication count were key predictors of future research productivity among ophthalmology residents in the US.

9.
J Adv Model Earth Syst ; 13(7): e2020MS002421, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34434490

RESUMEN

The Western United States is dominated by natural lands that play a critical role for carbon balance, water quality, and timber reserves. This region is also particularly vulnerable to forest mortality from drought, insect attack, and wildfires, thus requiring constant monitoring to assess ecosystem health. Carbon monitoring techniques are challenged by the complex mountainous terrain, thus there is an opportunity for data assimilation systems that combine land surface models and satellite-derived observations to provide improved carbon monitoring. Here, we use the Data Assimilation Research Testbed to adjust the Community Land Model (CLM5.0) with remotely sensed observations of leaf area and above-ground biomass. The adjusted simulation significantly reduced the above-ground biomass and leaf area, leading to a reduction in both photosynthesis and respiration fluxes. The reduction in the carbon fluxes mostly offset, thus both the adjusted and free simulation projected a weak carbon sink to the land. This result differed from a separate observation-constrained model (FLUXCOM) that projected strong carbon uptake to the land. Simulation diagnostics suggested water limitation had an important influence upon the magnitude and spatial pattern of carbon uptake through photosynthesis. We recommend that additional observations important for water cycling (e.g., snow water equivalent, land surface temperature) be included to improve the veracity of the spatial pattern in carbon uptake. Furthermore, the assimilation system should be enhanced to maximize the number of the simulated state variables that are adjusted, especially those related to the recommended observed quantities including water cycling and soil carbon.

10.
R I Med J (2013) ; 104(7): 55-58, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34437667

RESUMEN

PURPOSE: Concern about the decline in physician scientists has generated interest in promoting research participation among medical students. This study aimed to examine perceptions of research and research-oriented careers among college-level baccalaureate-MD (BA/MD) students at one institution in the United States. METHODS: A cross-sectional survey was distributed to a sample of 241 BA/MD students. Descriptive statistics were used to examine research perceptions of participants. RESULTS: The response rate was 52% (126/241). Most respondents conducted scientific research in high school and were interested in research-oriented careers. Most students participated in a research program (research course, faculty mentorship, or research grant), disseminated their research, and believed that research programs would be helpful for their research participation. The most common perceived barriers were a lack of time, interest, and prior research experience. CONCLUSIONS: College-level BA/MD students had positive perception of research-oriented careers and found student research programs helpful. However, addressing key barriers such as lack of time, interest and experience will help expand BA/MD student engagement in research.


Asunto(s)
Selección de Profesión , Estudiantes de Medicina , Estudios Transversales , Humanos , Mentores , Percepción , Estados Unidos
12.
Sci Rep ; 11(1): 14397, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34257348

RESUMEN

T-cell-redirecting bispecific antibodies have emerged as a new class of therapeutic agents designed to simultaneously bind to T cells via CD3 and to tumor cells via tumor-cell-specific antigens (TSA), inducing T-cell-mediated killing of tumor cells. The promising preclinical and clinical efficacy of TSAxCD3 antibodies is often accompanied by toxicities such as cytokine release syndrome due to T-cell activation. How the efficacy and toxicity profile of the TSAxCD3 bispecific antibodies depends on the binding affinity to CD3 remains unclear. Here, we evaluate bispecific antibodies that were engineered to have a range of CD3 affinities, while retaining the same binding affinity for the selected tumor antigen. These agents were tested for their ability to kill tumor cells in vitro, and their biodistribution, serum half-life, and anti-tumor activity in vivo. Remarkably, by altering the binding affinity for CD3 alone, we can generate bispecific antibodies that maintain potent killing of TSA + tumor cells but display differential patterns of cytokine release, pharmacokinetics, and biodistribution. Therefore, tuning CD3 affinity is a promising method to improve the therapeutic index of T-cell-engaging bispecific antibodies.


Asunto(s)
Anticuerpos Biespecíficos , Complejo CD3 , Citocinas , Citocinas/metabolismo , Activación de Linfocitos , Distribución Tisular
13.
Crit Care Med ; 49(10): 1779-1789, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34259438

RESUMEN

OBJECTIVES: To describe mechanical ventilation management and factors associated with nonadherence to lung-protective ventilation principles in pediatric acute respiratory distress syndrome. DESIGN: A planned ancillary study to a prospective international observational study. Mechanical ventilation management (every 6 hr measurements) during pediatric acute respiratory distress syndrome days 0-3 was described and compared with Pediatric Acute Lung Injury Consensus Conference tidal volume recommendations (< 7 mL/kg in children with impaired respiratory system compliance, < 9 mL/kg in all other children) and the Acute Respiratory Distress Syndrome Network lower positive end-expiratory pressure/higher Fio2 grid recommendations. SETTING: Seventy-one international PICUs. PATIENTS: Children with pediatric acute respiratory distress syndrome. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Analyses included 422 children. On pediatric acute respiratory distress syndrome day 0, median tidal volume was 7.6 mL/kg (interquartile range, 6.3-8.9 mL/kg) and did not differ by pediatric acute respiratory distress syndrome severity. Plateau pressure was not recorded in 97% of measurements. Using delta pressure (peak inspiratory pressure - positive end-expiratory pressure), median tidal volume increased over quartiles of median delta pressure (p = 0.007). Median delta pressure was greater than or equal to 18 cm H2O for all pediatric acute respiratory distress syndrome severity levels. In severe pediatric acute respiratory distress syndrome, tidal volume was greater than or equal to 7 mL/kg 62% of the time, and positive end-expiratory pressure was lower than recommended by the positive end-expiratory pressure/Fio2 grid 70% of the time. In multivariable analysis, tidal volume nonadherence was more common with severe pediatric acute respiratory distress syndrome, fewer PICU admissions/yr, non-European PICUs, higher delta pressure, corticosteroid use, and pressure control mode. Adherence was associated with underweight stature and cuffed endotracheal tubes. In multivariable analysis, positive end-expiratory pressure/Fio2 grid nonadherence was more common with higher pediatric acute respiratory distress syndrome severity, ventilator decisions made primarily by the attending physician, pre-ICU cardiopulmonary resuscitation, underweight stature, and age less than 2 years. Adherence was associated with respiratory therapist involvement in ventilator management and longer time from pediatric acute respiratory distress syndrome diagnosis. Higher nonadherence to tidal volume and positive end-expiratory pressure recommendations were independently associated with higher mortality and longer duration of ventilation after adjustment for confounding variables. In stratified analyses, these associations were primarily influenced by children with severe pediatric acute respiratory distress syndrome. CONCLUSIONS: Nonadherence to lung-protective ventilation principles is common in pediatric acute respiratory distress syndrome and may impact outcome. Modifiable factors exist that may improve adherence.


Asunto(s)
Adhesión a Directriz/normas , Síndrome de Dificultad Respiratoria/prevención & control , Adolescente , Niño , Preescolar , Femenino , Adhesión a Directriz/estadística & datos numéricos , Humanos , Incidencia , Lactante , Unidades de Cuidado Intensivo Pediátrico/organización & administración , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Modelos Logísticos , Masculino , Estudios Prospectivos , Respiración Artificial/métodos , Respiración Artificial/estadística & datos numéricos , Síndrome de Dificultad Respiratoria/epidemiología , Síndrome de Dificultad Respiratoria/terapia
14.
Implement Sci Commun ; 2(1): 77, 2021 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-34274004

RESUMEN

BACKGROUND: Few validated assessment tools are available to increase understanding and measure factors associated with sustainment of clinical practices, an increasingly recognized need among clinicians. We describe the development of the Clinical Sustainability Assessment Tool (CSAT), designed to assess factors that contribute to sustainable practices in clinical settings. METHODS: Sixty-four participants from clinical and research fields participated in concept mapping and were recruited to brainstorm factors that lead to sustained clinical practices. Once repeated factors were removed, participants sorted items based on similarity and rated them by importance and feasibility. Using concept mapping analyses, items were grouped into meaningful domains to develop an initial tool. We then recruited pilot sites and early adopters, for a total of 286 practicing clinicians, to pilot and evaluate the tool. Individuals were recruited from clinical settings across pediatric and adult medical and surgical subspecialties. The data were analyzed using confirmatory factor analysis (CFA) to test hypothesized subscale structure in the instrument. We used root mean square error of approximation (RMSEA) and the standardized root mean square residual (SRMR) to assess fit and thus the ability of CSAT to measure the identified domains. RESULTS: The concept mapping produced sorted statements that were edited into items that could be responded to, resulting in the creation of a tool with seven determinant domains and 47 items. The pilot and CFA testing resulted in a final CSAT instrument made up 35 items, five per domain. CFA results demonstrated very good fit of the seven domain structure of the CSAT (RMSEA = 0.049; SRMR = 0.049). Usability testing indicated the CSAT is brief, easy to use, easy to learn, and does not require extensive training. Additionally, the measure scored highly (18/20) on the Psychometric and Pragmatic Evidence Rating Scale (PAPERS). The seven final CSAT domains were engaged staff and leadership, engaged stakeholders, organizational readiness, workflow integration, implementation and training, monitoring and evaluation, and outcomes and effectiveness. CONCLUSIONS: The CSAT is a new reliable assessment tool which allows for greater practical and scientific understanding of contextual factors that enable sustainable clinical practices over time.

15.
Front Cardiovasc Med ; 8: 637106, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34179125

RESUMEN

Purpose: We sought to determine the impact of a comprehensive, context-responsive anticoagulation and transfusion guideline on bleeding and thrombotic complication rates and blood product utilization during extracorporeal membrane oxygenation (ECMO). Design: Single-center, observational pre- and post-implementation cohort study. Setting: Academic pediatric hospital. Patients: Patients in the PICU, CICU, and NICU receiving ECMO support. Interventions: Program-wide implementation of a context-responsive anticoagulation and transfusion guideline. Measurements: Pre-implementation subjects consisted of all patients receiving ECMO between January 1 and December 31, 2012, and underwent retrospective chart review. Post-implementation subjects consisted of all ECMO patients between September 1, 2013, and December 31, 2014, and underwent prospective data collection. Data collection included standard demographic and admission data, ECMO technical specifications, non-ECMO therapies, coagulation parameters, and blood product administration. A novel grading scale was used to define hemorrhagic complications (major, intermediate, and minor) and major thromboembolic complications. Main Results: Seventy-six ECMO patients were identified: 31 during the pre-implementation period and 45 in the post-implementation period. The overall observed mortality was 33% with no difference between groups. Compared to pre-implementation, the post-implementation group experienced fewer major hemorrhagic and major thrombotic complications and less severe hemorrhagic complications and received less RBC transfusion volume per kg. Conclusions: Use of a context-responsive anticoagulation and transfusion guideline was associated with a reduction in hemorrhagic and thrombotic complications and reduced RBC transfusion requirements. Further evaluation of guideline content, compliance, performance, and sustainability is needed.

16.
Earth Space Sci ; 8(4): e2020EA001343, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33869670

RESUMEN

A growing constellation of satellites is providing near-global coverage of column-averaged CO2 observations. Launched in 2019, NASA's OCO-3 instrument is set to provide XCO2 observations at a high spatial and temporal resolution for regional domains (100 × 100 km). The atmospheric column version of the Stochastic Time-Inverted Lagrangian Transport (X-STILT) model is an established method of determining the influence of upwind sources on column measurements of the atmosphere, providing a means of analysis for current OCO-3 observations and future space-based column-observing missions. However, OCO-3 is expected to provide hundreds of soundings per targeted observation, straining this already computationally intensive technique. This work proposes a novel scheme to be used with the X-STILT model to generate upwind influence footprints with less computational expense. The method uses X-STILT generated influence footprints from a key subset of OCO-3 soundings. A nonlinear weighted averaging is applied to these footprints to construct additional footprints for the remaining soundings. The effects of subset selection, meteorological data, and topography are investigated for two test sites: Los Angeles, California, and Salt Lake City, Utah. The computational time required to model the source sensitivities for OCO-3 interpretation was reduced by 62% and 78% with errors smaller than other previously acknowledged uncertainties in the modeling system (OCO-3 retrieval error, atmospheric transport error, prior emissions error, etc.). Limitations and future applications for future CO2 missions are also discussed.

17.
R I Med J (2013) ; 104(1): 61-64, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33517603

RESUMEN

OBJECTIVE: To assess the impact of the COVID-19 pandemic and associated lockdowns on public interest in ophthalmology. METHODS: Search interest data for ophthalmic services and conditions were collected from January 1, 2019 to June 21, 2020. Temporal statistical analysis was used to identify significant trends. Weekly data on ophthalmic services and conditions search interest obtained from Google Trends were analyzed with analysis of variance testing and the generalized linear model based on dates. RESULTS: Ophthalmic services searches decreased after the first COVID-19 case in the country (p<0.001); ophthalmic services and conditions search interest also declined after the first COVID-19 case and lockdown orders in each state (p<0.001). Following the first in-state COVID-19 case, search interest in ophthalmic services fell more than for ophthalmic conditions (p=0.0088). Lockdown and COVID-19 had similar effects on ophthalmic services search interest (p=0.2246), but interest in ophthalmic conditions decreased more after lockdown than after the first in-state case (p<0.0001). CONCLUSIONS: Most of the decrease in search interest in ophthalmic services was associated with COVID-19 rather than lockdown orders, suggesting that public interest in ophthalmic care may be more sensitive to changes in the COVID-19 pandemic than lockdown orders.


Asunto(s)
COVID-19/epidemiología , Oftalmopatías/epidemiología , Conducta en la Búsqueda de Información , Oftalmología , COVID-19/prevención & control , COVID-19/psicología , Oftalmopatías/terapia , Humanos , Sistemas en Línea , Oftalmología/estadística & datos numéricos , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Cuarentena
18.
J Child Neurol ; 36(3): 230-236, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33112194

RESUMEN

OBJECTIVE: Determine seizure frequency and association with neurologic outcomes in infants undergoing extracorporeal membrane oxygenation. Identify patient or clinical factors associated with seizures or brain injury on imaging. METHODS: Retrospective, single-center study including infants less than 1 year of age, who underwent extracorporeal membrane oxygenation between 2012 and 2017. RESULTS: A total of 104 infants met study criteria including 45 patients with continuous electroencephalographic (EEG) monitoring during their extracorporeal membrane oxygenation run and 59 infants without EEG. Seizures (electrographic-only or electro-clinical) were identified in 18 of the 45 (40%). Among the 18 infants with seizures, 14 (78%) had moderate to severe brain injury, whereas only 44% of those without seizures (12 of 27) on EEG had moderate to severe brain injury (P = .03). Cardiopulmonary resuscitation prior to extracorporeal membrane oxygenation (ECPR), mode of extracorporeal membrane oxygenation, length of stay, survival to discharge, and congenital heart disease were not associated with seizures. One of 10 patients with cyanotic congenital heart disease due to hypoplastic left heart syndrome had seizures compared with 7 of 10 patients with non-hypoplastic left heart syndrome lesions (P = .02). Seizures were associated with moderate to severe brain injury, after adjusting for ECPR and congenital heart disease (P = .04). CONCLUSIONS: Electrographic seizures were common in patients undergoing extracorporeal membrane oxygenation and higher than previously reported. Seizures were associated with moderate to severe abnormalities on imaging, after adjusting for ECPR and congenital heart disease. This study adds to recent literature describing the risk of seizures in patients on extracorporeal membrane oxygenation and highlights the presence of brain injuries that may be identified by routine EEG surveillance.

19.
J Am Chem Soc ; 143(2): 588-592, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33382947

RESUMEN

The electrochemical CO2 reduction reaction (CO2RR) using Cu-based catalysts holds great potential for producing valuable multi-carbon products from renewable energy. However, the chemical and structural state of Cu catalyst surfaces during the CO2RR remains a matter of debate. Here, we show the structural evolution of the near-surface region of polycrystalline Cu electrodes under in situ conditions through a combination of grazing incidence X-ray absorption spectroscopy (GIXAS) and X-ray diffraction (GIXRD). The in situ GIXAS reveals that the surface oxide layer is fully reduced to metallic Cu before the onset potential for CO2RR, and the catalyst maintains the metallic state across the potentials relevant to the CO2RR. We also find a preferential surface reconstruction of the polycrystalline Cu surface toward (100) facets in the presence of CO2. Quantitative analysis of the reconstruction profiles reveals that the degree of reconstruction increases with increasingly negative applied potentials, and it persists when the applied potential returns to more positive values. These findings show that the surface of Cu electrocatalysts is dynamic during the CO2RR, and emphasize the importance of in situ characterization to understand the surface structure and its role in electrocatalysis.

20.
Environ Sci Technol ; 54(24): 15613-15621, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33274635

RESUMEN

Urban environments are characterized by pronounced spatiotemporal heterogeneity, which can present sampling challenges when utilizing conventional greenhouse gas (GHG) measurement systems. In Salt Lake City, Utah, a GHG instrument was deployed on a light rail train car that continuously traverses the Salt Lake Valley (SLV) through a range of urban typologies. CO2 measurements from a light rail train car were used within a Bayesian inverse modeling framework to constrain urban emissions across the SLV during the fall of 2015. The primary objectives of this study were to (1) evaluate whether ground-based mobile measurements could be used to constrain urban emissions using an inverse modeling framework and (2) quantify the information that mobile observations provided relative to conventional GHG monitoring networks. Preliminary results suggest that ingesting mobile measurements into an inverse modeling framework generated a posterior emission estimate that more closely aligned with observations, reduced posterior emission uncertainties, and extends the geographical extent of emission adjustments.


Asunto(s)
Gases de Efecto Invernadero , Teorema de Bayes , Ciudades , Efecto Invernadero , Gases de Efecto Invernadero/análisis , Lagos , Utah
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