Importance of composition and hygroscopicity of BC particles to the effect of BC mitigation on cloud properties: Application to California conditions

Black carbon (BC) has many effects on climate including the direct effect on atmospheric absorption, indirect and semi-direct effects on clouds, snow effects, and others. While most of these are positive (warming), the first indirect effect is negative and quantifying its magnitude in addition to other BC feedbacks is important for supporting policies that mitigate BC. We use the detailed aerosol chemistry parcel model of Russell and Seinfeld (1998), observationally constrained by initial measured aerosol concentrations from five California sites, to provide simulated cloud drop number (CDN) concentrations against which two GCM calculations – one run at the global scale and one nested from the global-to-regional scale are compared. The GCM results reflect the combined effects of their emission inventories, advection schemes, and cloud parameterizations. BC-type particles contributed between 16 and 20% of cloud droplets at all sites even in the presence of more hygroscopic particles. While this chemically detailed parcel model result is based on simplified cloud dynamics and does not consider semi-direct or cloud absorption effects, the cloud drop number concentrations are similar to the simulations of both Chen et al. (2010b) and Jacobson (2010) for the average cloud conditions in California. Reducing BC particle concentration by 50% decreased the cloud droplet concentration by between 6% and 9% resulting in the formation of fewer, larger cloud droplets that correspond to a lower cloud albedo. This trend is similar to Chen et al. (2010b) and Jacobson (2010) when BC particles were modeled as hygroscopic. This reduction in CDN in California due to the decrease in activated BC particles supports the concern raised by Chen et al. (2010a) that the cloud albedo effect of BC particles has a cooling effect that partially offsets the direct forcing reduction if other warming effects of BC on clouds are unchanged. These results suggests that for regions like the California sites studied here, where BC mitigation targets fossil fuel sources, a critical aspect of the modeled reduction is the chemical composition and associated hygroscopicity of the BC particles removed as well as their relative contribution to the atmospheric particle concentrations

Diagnostic errors in paediatric cardiac intensive care

AbstractIntroductionDiagnostic errors cause significant patient harm and increase costs. Data characterising such errors in the paediatric cardiac intensive care population are limited. We sought to understand the perceived frequency and types of diagnostic errors in the paediatric cardiac ICU.MethodsPaediatric cardiac ICU practitioners including attending and trainee physicians, nurse practitioners, physician assistants, and registered nurses at three North American tertiary cardiac centres were surveyed between October 2014 and January 2015.ResultsThe response rate was 46% (N=200). Most respondents (81%) perceived that diagnostic errors harm patients more than five times per year. More than half (65%) reported that errors permanently harm patients, and up to 18% perceived that diagnostic errors contributed to death or severe permanent harm more than five times per year. Medication side effects and psychiatric conditions were thought to be most commonly misdiagnosed. Physician groups also ranked pulmonary overcirculation and viral illness to be commonly misdiagnosed as bacterial illness. Inadequate care coordination, data assessment, and high clinician workload were cited as contributory factors. Delayed diagnostic studies and interventions related to the severity of the patient’s condition were thought to be the most commonly reported process breakdowns. All surveyed groups ranked improving teamwork and feedback pathways as strategies to explore for preventing future diagnostic errors.ConclusionsPaediatric cardiac intensive care practitioners perceive that diagnostic errors causing permanent harm are common and associated more with systematic and process breakdowns than with cognitive limitations.</jats:sec

Left ventricular assist device implantation after acute anterior wall myocardial infarction and cardiogenic shock: A two-center study

ObjectiveLeft ventricular assist device (LVAD) insertion after anterior wall myocardial infarction complicated by cardiogenic shock is an accepted modality of support in select patients. Results of primary revascularization for these patients are poor. We seek to determine the outcomes of patients with myocardial infarction and shock who undergo LVAD insertion alone versus surgical revascularization before LVAD insertion.MethodsSeventy-four patients at 2 institutions underwent LVAD implantation for myocardial infarction and shock over a 12-year period. Twenty-eight underwent direct LVAD placement, and 46 underwent revascularization through coronary artery bypass grafting before LVAD placement. Variables examined included patient demographics, myocardial infarction–LVAD interval, bridge to transplantation, early mortality (≤30 days), survival after LVAD placement, and posttransplantation survivals.ResultsThere were no differences in demographics between the 2 groups. The group undergoing revascularization before LVAD placement had a lower bridge to transplantation, higher early mortality, and lower overall 6- and 12-month survivals after LVAD placement compared with the group undergoing direct LVAD placement (45.50% vs 70.40%, P = .041; 39.10% vs 14.30%, P = .020; 89.3% and 82.1% vs 54.4% and 52.2%, respectively, P = .006). Posttransplantation survival and LVAD explantation rates were equivalent in both groups.ConclusionsCoronary artery bypass grafting before LVAD insertion for cardiogenic shock complicating myocardial infarction adversely affects survival. Confirmation of these findings would require conducting a large, multicenter, randomized clinical trial comparing revascularization versus LVAD support as primary therapy in this setting

PR-EDB: Power Reactor Embrittlement Database - Version 3

The aging and degradation of light-water reactor pressure vessels is of particular concern because of their relevance to plant integrity and the magnitude of the expected irradiation embrittlement. The radiation embrittlement of reactor pressure vessel materials depends on many factors, such as neutron fluence, flux, and energy spectrum, irradiation temperature, and preirradiation material history and chemical compositions. These factors must be considered to reliably predict pressure vessel embrittlement and to ensure the safe operation of the reactor. Large amounts of data from surveillance capsules are needed to develop a generally applicable damage prediction model that can be used for industry standards and regulatory guides. Furthermore, the investigations of regulatory issues such as vessel integrity over plant life, vessel failure, and sufficiency of current codes, Standard Review Plans (SRPs), and Guides for license renewal can be greatly expedited by the use of a well-designed computerized database. The Power Reactor Embrittlement Database (PR-EDB) is such a comprehensive collection of data for U.S. designed commercial nuclear reactors. The current version of the PR-EDB lists the test results of 104 heat-affected-zone (HAZ) materials, 115 weld materials, and 141 base materials, including 103 plates, 35 forgings, and 3 correlation monitor materials that were irradiated in 321 capsules from 106 commercial power reactors. The data files are given in dBASE format and can be accessed with any personal computer using the Windows operating system. "User-friendly" utility programs have been written to investigate radiation embrittlement using this database. Utility programs allow the user to retrieve, select and manipulate specific data, display data to the screen or printer, and fit and plot Charpy impact data. The PR-EDB Version 3.0 upgrades Version 2.0. The package was developed based on the Microsoft .NET framework technology and uses Microsoft Access for backend data storage, and Microsoft Excel for plotting graphs. This software package is compatible with Windows (98 or higher) and has been built with a highly versatile user interface. PR-EDB Version 3.0 also contains an "Evaluated Residual File" utility for generating the evaluated processed files used for radiation embrittlement study

Perspectives of Health Care Staff On Predictors of Success in a Food Prescription Program: a Qualitative Study

Partnerships between food prescription programs and food banks can address food insecurity and support health; however, few studies have examined the experience and perceptions of health care partners about these programs. Our objective was to analyze secondary qualitative data from clinicians and clinic staff involved in implementing a food prescription program in Houston, Texas. We collected data from 17 health care clinics from May 2018 through March 2021 to learn how implementation of the food prescription program was perceived, and we received 252 responses. Principal themes were the importance of a value-based care strategy, patient and food pantry barriers to success, the importance of interorganizational care coordination, and the need to integrate food prescriptions into clinic workflow. Insights of clinicians and clinic staff on implementation of food prescription programs can inform program development and dissemination

Postcardiac transplant survival in the current era in patients receiving continuous-flow left ventricular assist devices

ObjectivesContinuous-flow left ventricular assist devices have become the standard of care for patients with heart failure requiring mechanical circulatory support as a bridge to transplant. However, data on long-term post-transplant survival for these patients are limited. We evaluated the effect of continuous-flow left ventricular assist devices on postcardiac transplant survival in the current era.MethodsAll patients who received a continuous-flow left ventricular assist device as a bridge to transplant at a single center from June 2005 to September 2011 were evaluated.ResultsOf the 167 patients who received a continuous-flow left ventricular assist device as a bridge to transplant, 77 (46%) underwent cardiac transplantation, 27 died before transplantation (16%), and 63 (38%) remain listed for transplantation and continued with left ventricular assist device support. The mean age of the transplanted patients was 54.5 ± 11.9 years, 57% had an ischemic etiology, and 20% were women. The overall mean duration of left ventricular assist device support before transplantation was 310 ± 227 days (range, 67-1230 days). The mean duration of left ventricular assist device support did not change in patients who had received a left ventricular assist device in the early period of the study (2005-2008, n = 62) compared with those who had received a left ventricular assist device later (2009-2011, n = 78, 373 vs 392 days, P = NS). In addition, no difference was seen in survival between those patients supported with a left ventricular assist device for fewer than 180 days or longer than 180 days before transplantation (P = NS). The actuarial survival after transplantation at 30 days and 1, 3, and 5 years by Kaplan-Meier analysis was 98.7%, 93.0%, 91.1%, and 88.0%, respectively.ConclusionsThe short- and long-term post-transplant survival for patients bridged with a continuous-flow left ventricular assist device in the current era has been excellent. Furthermore, the duration of left ventricular assist device support did not affect post-transplant survival. The hemodynamic benefits of ventricular unloading with continuous-flow left ventricular assist devices, in addition to their durability and reduced patient morbidity, have contributed to improved post-transplant survival

Outcomes of Adult Patients with Small Body Size Supported with a Continuous-Flow Left Ventricular Assist Device

There is insufficient data on patients with small body size to determine if this should be considered a risk factor for continuous-flow left ventricular assist device (CF-LVAD) support. We sought to evaluate survival outcomes, adverse events, and functional status of CF-LVAD patients with body surface area (BSA) <1.5 m2 in a large national registry. Adults with BSA < 1.5 m2 (n = 128) implanted with a HeartMate II (HMII)-LVAD from the Interagency Registry for Mechanically Assisted Circulatory Support registry from April 2008 to December 2012 formed this cohort. Outcomes were compared with HMII bridge to transplant (BTT) and destination therapy (DT) post approval studies. The majority of patients were female (n = 106, 83%). A total of 64% (n = 82) were implanted for BTT and 36% (n = 46) for DT. The median BSA (range) was 1.44 (1.19–1.49) and 1.45 (1.25–1.49) m2 for BTT and DT, respectively. Overall survival 1 year post implant was 81% ± 5% for BTT and 84% ± 6% for DT. The most common adverse events for BTT and DT patients were bleeding (0.91, 0.88 events/patient year) and driveline infection (16%, 0.28 events/patient year). Six months post implantation, 87% of BTT and 77% of DT patients were New York Heart Association functional class I or II. Post implant survival, functional status improvement, and adverse event profile for adult BTT and DT HMII patients with BSA < 1.5 m2 are favorable and comparable with outcomes published in the overall patient population

Clinical Outcomes of a Large-Scale, Partnership-Based Regional Food Prescription Program: Results of a Quasi-Experimental Study

BACKGROUND: Food prescription programs are gaining interest from funders, policy makers, and healthcare payers as a way to provide value-based care. A small body of research suggests that such programs effectively impact health outcomes; however, the quality of existing studies is variable, and most studies use small samples. This study attempts to address these gaps by utilizing a quasi-experimental design with non-equivalent controls, to evaluate clinical outcomes among participants enrolled in a food prescription program implemented at scale. METHODS: We completed a secondary analysis of participant enrollment and utilization data collected between May 2018 and March 2021, by the Houston Food Bank as part of its multi-institution food prescription program. Enrollment data was obtained from 16 health care partners and redemption data from across 40 food pantries in Houston, Texas. Our objective was to assess if program participation impacted multiple cardio-metabolic markers. Exposure was defined as any visit to a food pantry after receipt of prescription. Linear and logistic regression models were used to estimate change in outcomes by exposure status and number of food pantry visits. RESULTS: Exposed patients experienced a -0.28% (p = 0.007) greater change in HbA1c than unexposed patients, over six months. Differences across exposure categories were seen with systolic blood pressure (-3.2, p \u3c 0.001) and diastolic blood pressure (-2.5, p = 0.028), over four months. The odds of any decline in HbA1c (OR = 1.06 per visit, p \u3c 0.001) and clinically meaningful decline in HbA1c (OR = 1.04 per visit, p = 0.007) showed a linear association with visit frequency. CONCLUSIONS: Our study of a large food prescription program involving multiple health care and food pantry sites provides robust evidence of a modest decline in HbA1c levels among participants. These results confirm that food prescription programs can continue to be effective at scale, and portend well for institutionalization of such programs