OPTICAL AND SINGLE PARTICLE PROPERTIES OF NORTH ATLANTIC FREE TROPOSPHERIC AEROSOLS AND IMPLICATIONS FOR AEROSOL DIRECT RADIATIVE FORCING

Human-induced climate change has steadily become a reality rather than a possibility. One factor that plays into climate change is radiative forcing due to aerosol-radiation interactions (ARI). As such, it is important to understand how aerosols (atmospheric particles) interact with solar radiation. This work looks at seven samples of well-aged aerosols (aerosols traveling in the atmosphere for at least a few days) collected at Pico Mountain Observatory in the summer of 2015. Pico Mountain Observatory is located in a remote, high elevation site in the Azores, in the Eastern-North Atlantic Ocean. The goals of the study were to analyze the physicochemical properties of these atmospheric particles and to unravel potential relations with their radiative properties. From single particle analysis, it was found that all samples contained predominantly carbon-based aerosols, with smaller amounts of sea salt and mineral dust observed in some samples. Modeled atmospheric transport paths indicated most sampled particles came from North America with long transport times. The particles in all samples were internally mixed, further supporting the expectation and modeling findings that the sampled particles were well-aged. Two selected samples, one dominated by biomass burning, and a second affected by mineral dust, were compared in more detail. Radiative forcing calculations have been performed for the particles collected during two events. The calculations were performed for two scenarios with different reflectances of the surfaces underneath: clear sky ocean and clouds. It was found that there is potential cooling over areas of low albedo, such as the clear sky ocean, and potential warming over areas of high albedo, such as above clouds

Substance use screening and brief intervention: Evaluation of patient and implementation differences between primary care and emergency department settings

RATIONALE, AIMS, AND OBJECTIVES: There are well-documented barriers that have limited widespread, sustained adoption of screening and brief intervention for risky substance use in health care settings. In order to better inform implementation efforts, this study evaluates whether patient characteristics, screening results, and implementation success indicators differed between two clinical setting types: primary care and emergency. METHODS: Patients presenting to an emergency or primary care setting were screened for risky substance use (n = 41 567). Patients with a positive screen were further assessed for psychosocial, health, and substance use problems (n = 1604). Differences in patient characteristics between primary care and emergency settings were examined using chi-square and t tests. Multilevel logistic regression was used to examine whether setting type predicted screening results. Site-level indicators of implementation success were calculated (percentage prescreens completed, percentage full screens completed, and percentage refused services) for all patient visits (n = 78 656). RESULTS: As compared with primary care patients, emergency patients had more severe substance use patterns and screening scores, were more likely to use a variety of illicit drugs, and reported more psychosocial issues. In logistic regression models, setting type did not predict whether patients screened positive; however, it did predict screening into a higher vs lower risk category such that emergency patients were more likely to be in a higher risk category. Emergency settings had lower indicators of implementation success (eg, 14% lower prescreen completion rate) as compared with primary care settings on some implementation measures. CONCLUSIONS: This evaluation found important differences in patient characteristics and screening and implementation results between primary care and emergency settings. Health care organizations and administrators implementing screening and brief intervention should attend to setting differences that could affect implementation and clinical care

Substance use screening and brief intervention: Evaluation of patient and implementation differences between primary care and emergency department settings.

RATIONALE, AIMS, AND OBJECTIVES: There are well-documented barriers that have limited widespread, sustained adoption of screening and brief intervention for risky substance use in health care settings. In order to better inform implementation efforts, this study evaluates whether patient characteristics, screening results, and implementation success indicators differed between two clinical setting types: primary care and emergency. METHODS: Patients presenting to an emergency or primary care setting were screened for risky substance use (n = 41 567). Patients with a positive screen were further assessed for psychosocial, health, and substance use problems (n = 1604). Differences in patient characteristics between primary care and emergency settings were examined using chi-square and t tests. Multilevel logistic regression was used to examine whether setting type predicted screening results. Site-level indicators of implementation success were calculated (percentage prescreens completed, percentage full screens completed, and percentage refused services) for all patient visits (n = 78 656). RESULTS: As compared with primary care patients, emergency patients had more severe substance use patterns and screening scores, were more likely to use a variety of illicit drugs, and reported more psychosocial issues. In logistic regression models, setting type did not predict whether patients screened positive; however, it did predict screening into a higher vs lower risk category such that emergency patients were more likely to be in a higher risk category. Emergency settings had lower indicators of implementation success (eg, 14% lower prescreen completion rate) as compared with primary care settings on some implementation measures. CONCLUSIONS: This evaluation found important differences in patient characteristics and screening and implementation results between primary care and emergency settings. Health care organizations and administrators implementing screening and brief intervention should attend to setting differences that could affect implementation and clinical care

Intravenous TPA for Ischemic Stroke Patients: Houston Experience 1996–2000

Background: Implementation of intravenous (IV) tissue plasminogen activator (TPA) therapy with the NINDS protocol has been reported with variable safety. Our center has an experienced stroke team of fellows and stroke faculty servicing one University hospital and three community hospitals. Methods: We report our experience in the treatment of 269 consecutive patients with ischemic stroke within the first 3 hours after symptom onset with 0.9 mg/kg IV TPA according to the NINDS protocol. Results: A total of 269 patients were treated between 1/96 and 6/00: median age 69 (range 24–93 years, females 48%). Pre-treatment NIHSS was 14±6 (median 14, range 4–33 points). TPA bolus was given at 137 min (range 30–180 minutes) with 28% of patients treated within 2 hours. Median door-to-needle time was 68 minutes (range 10–129 minutes). Overall symptomatic ICH rate was 4.5% (range 2.6% - 8.7% between hospitals, ns), with a decline noted from 1996 to 2000 (Table). Protocol violations (excessive blood pressure, seizure at onset) were found in 13% of all patients and symptomatic ICH rate in these patients was 15%. At 24 hours NIHSS score was 9±8 (median 8, range 0–36 points). In hospital mortality was 15% and discharge NIHSS score was 6±7 (median 3, range 0–36). Long-term follow-up will be reported. Conclusions: Intravenous TPA in a dose of 0.9 mg/kg can be given with a risk of symptomatic ICH lower than previously reported. Safety of TPA improved from 1996 to 2000. We conclude that the safety of TPA therapy depends more on the expertise of the treating team than the type of the hospital

Intravenous Tissue-Type Plasminogen Activator Therapy for Ischemic Stroke

Context Intravenous tissue-type plasminogen activator (tPA) therapy using the National Institute of Neurological Disorders and Stroke criteria has been given with variable safety to less than 5% of the patients who have ischemic strokes nationwide. Our center is experienced in treating large numbers of stroke patients with intravenous tPA. Objective To report our total 4-year experience in the treatment of consecutive patients who had an ischemic stroke. Design Prospective inception cohort registry of all patients seen by our stroke team and an additional retrospective medical record review of all patients treated between January 1, 1996, and June 1, 2000. Setting A veteran stroke team composed of fellows and stroke-specialty faculty servicing 1 university and 3 community hospitals in a large urban setting. Patients Consecutive patients with ischemic stroke treated within the first 3 hours of symptom onset. Intervention According to the National Institute of Neurological Disorders and Stroke protocol, 0.9 mg/kg of intravenous tissue-type plasminogen activator was administered. Main Outcome Measures Number and proportion treated, patient demographics, time to treatment, hemorrhage rates, and clinical outcome. Results A total of 269 patients were treated between January 1, 1996, and June 1, 2000. Their mean age was 68 years (age range, 24-93 years); 48% were women. This represented 9% of all patients admitted with symptoms of cerebral ischemia at our most active hospital (over the final 6 months, 13% of all patients with symptoms of cerebral ischemia and 15% of all acute ischemic stroke patients). Before treatment the mean ± SD National Institutes of Health Stroke Scale (NIHSS) score was 14.4 ± 6.1 points (median, 14 points; range, 4-33 points). A tPA bolus was given at 137 minutes (range, 30-180 minutes); 28% of the patients were treated within 2 hours. The mean door-to-needle time was 70 minutes (range, 10-129 minutes). The symptomatic intracerebral hemorrhage rate was 5.6% of those patients with a second set of brain scans (4.5% of all patients), with a declining trend from 1996 to 2000. Protocol violations were found in 13% of all patients; the symptomatic intracerebral hemorrhage rate in these patients was 15%. At 24 hours, the NIHSS score was 10 ± 8 points (median, 8 points; range, 0-36 points). In-hospital mortality was 15% and the patients\u27 discharge NIHSS scores were 7 ± 7 points (median, 3 points; range, 0-35 points). Conclusions Intravenous tPA therapy can be given to up to 15% of the patients with acute ischemic stroke with a low risk of symptomatic intracerebral hemorrhage. Successful experience with intravenous tPA therapy depends on the experience and organization of the treating team and adherence to published guidelines