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1.
J Adv Model Earth Syst ; 13(4): e2020MS002413, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34221240

ABSTRACT

The Goddard Earth Observing System composition forecast (GEOS-CF) system is a high-resolution (0.25°) global constituent prediction system from NASA's Global Modeling and Assimilation Office (GMAO). GEOS-CF offers a new tool for atmospheric chemistry research, with the goal to supplement NASA's broad range of space-based and in-situ observations. GEOS-CF expands on the GEOS weather and aerosol modeling system by introducing the GEOS-Chem chemistry module to provide hindcasts and 5-days forecasts of atmospheric constituents including ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and fine particulate matter (PM2.5). The chemistry module integrated in GEOS-CF is identical to the offline GEOS-Chem model and readily benefits from the innovations provided by the GEOS-Chem community. Evaluation of GEOS-CF against satellite, ozonesonde and surface observations for years 2018-2019 show realistic simulated concentrations of O3, NO2, and CO, with normalized mean biases of -0.1 to 0.3, normalized root mean square errors between 0.1-0.4, and correlations between 0.3-0.8. Comparisons against surface observations highlight the successful representation of air pollutants in many regions of the world and during all seasons, yet also highlight current limitations, such as a global high bias in SO2 and an overprediction of summertime O3 over the Southeast United States. GEOS-CF v1.0 generally overestimates aerosols by 20%-50% due to known issues in GEOS-Chem v12.0.1 that have been addressed in later versions. The 5-days forecasts have skill scores comparable to the 1-day hindcast. Model skills can be improved significantly by applying a bias-correction to the surface model output using a machine-learning approach.

2.
Int J Med Educ ; 12: 101-124, 2021 May 28.
Article in English | MEDLINE | ID: mdl-34053914

ABSTRACT

OBJECTIVES: To describe the published literature on EBM curricula for physicians in training and barriers during curriculum implementation. METHODS: We performed a systematic search and review of the medical literature on PubMed, Embase, ERIC, Scopus and Web of Science from the earliest available date until September 4, 2019. RESULTS: We screened 9,042 references and included 29 full-text studies and 14 meeting abstracts. Eighteen studies had moderate validity, and 6 had high validity. The EBM curricular structure proved highly variable in between studies. The majority of the EBM curricula was longitudinal with different lengths. Only five studies reported using Kern's six-step approach for curriculum development. Twenty-one articles reported on EBM skills and knowledge, and only 5/29 full-text articles used a validated assessment tool. Time was the main barrier to EBM curriculum implementation. All the included studies and abstracts, independent of the EBM curriculum structure or evaluation method used, found an improvement in the residents' attitudes and/or EBM skills and knowledge. CONCLUSIONS: The current body of literature available to guide educators in EBM curriculum development is enough to constitute a strong scaffold for developing any EBM curriculum. Given the amount of time and resources needed to develop and implement an EBM curriculum, it is very important to follow the curriculum development steps and use validated assessment tools.


Subject(s)
Internship and Residency , Physicians , Attitude , Curriculum , Evidence-Based Medicine/education , Humans
3.
JACC Case Rep ; 1(1): 5-8, 2019 Jun.
Article in English | MEDLINE | ID: mdl-34316730

ABSTRACT

Malignant melanoma demonstrates the highest rate of cardiac metastases. The incidence of melanoma is rising. The prognosis of people with advanced melanoma is generally poor. This case report emphasizes the potential need for early detection of cardiac involvement in advanced melanoma in view of promising advances in treatment with immune checkpoint inhibitors. (Level of Difficulty: Advanced.).

4.
J Palliat Med ; 13(4): 407-12, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20384501

ABSTRACT

OBJECTIVE: To determine the pattern and characteristics of palliative care (PC) consultations in patients with stroke and compare them with the characteristics of nonstroke consultations. METHODS: The palliative care program at Strong Memorial Hospital (SMH) was established in October 2001. SMH is a 765-bed academic medical center with approximately 38,000 discharges. For each consult from 2005 to 2007, we collected demographic, clinical, and service-related information. We explored similarities and differences in patients with different types of stroke, including patients with ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and subdural hematoma. In addition, we compared these data to the nonstroke patients who had a palliative care consultation during the same time period. RESULTS: Over the 3-year period from 2005 to 2007, there were a total of 101 consultations in patients with stroke (6.3% of all PC consultations). Of the 101 consultations, 31 were in patients with ischemic stroke, 26 in patients with intracerebral hemorrhage, 30 in patients with subarachnoid hemorrhage, and 14 in patients with subdural hematoma. Patients with stroke who had a PC consult were more functionally impaired, less likely to have capacity, more likely to die in the hospital, and to have fewer traditional symptom burdens than other common diagnoses seen on the PC consultation service. The most common trajectory to death was withdrawal of mechanical ventilation, but varied by type of stroke. Common treatments negotiated in these consultations included mechanical ventilation, artificial nutrition, tracheostomy, and less likely antibiobics, intravenous fluids, and various neurosurgical procedures. CONCLUSIONS: Patients with stroke are a common diagnosis seen on an inpatient palliative care consult service. Each stroke type represents patients with potentially distinct palliative care needs.


Subject(s)
Hospitalization/statistics & numerical data , Palliative Care/methods , Referral and Consultation/statistics & numerical data , Stroke , Aged , Communication , Female , Health Status Indicators , Humans , Length of Stay , Male , Middle Aged , New York , Palliative Care/statistics & numerical data , Physician-Patient Relations
5.
J Hypertens ; 25(3): 707-12, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17278988

ABSTRACT

OBJECTIVE: The ambulatory blood pressure (ABP) monitoring substudy of the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial was carried out in a subset of patients from USA, Italy and Denmark. ABP was measured after 1 year in the trial, with the aim of evaluating comparability of ABP levels on valsartan (VAL) and amlodipine (AML)-based regimens. METHODS: ABP was measured every 20 min during a 25-h period after morning administration of medicine; 659 patients were available for intention-to-treat analysis. RESULTS: Office blood pressure (BP) differences were smaller than in the main study and mean ABP levels also showed only minor differences between the two regimens (VAL, 132.5/74.8 mmHg; AML, 131.5/75.2 mmHg). However, during the first 7 h after dosing, ABP was lower on VAL, whereas AML exerted a significantly stronger effect during the last 4 h of the dosing interval--possibly influencing the differences in office BP found in the main study. Mean heart rate (HR) was higher on AML (72.3 bpm) than on VAL (70.5 bpm) (P = 0.013), suggesting a sustained difference in sympathetic activation. Correlation analysis showed a close relationship between treated ABP levels and the occurrence of combined cardiovascular endpoints--superior to the relationship to office BP. CONCLUSIONS: In these elderly high-risk patients, diastolic ABP levels tended to be less predictive than systolic, and daytime less predictive than night-time for all cardiovascular endpoints. The findings underline the importance of ABP substudies in comparative trials for elucidating significant differences in pharmacodynamics, and stresses the superior predictive power of ABP.


Subject(s)
Antihypertensive Agents/therapeutic use , Blood Pressure Monitoring, Ambulatory , Circadian Rhythm/physiology , Hypertension/drug therapy , Tetrazoles/therapeutic use , Valine/analogs & derivatives , Age Factors , Aged , Amlodipine/pharmacology , Denmark , Female , Heart Rate/drug effects , Humans , Italy , Male , Middle Aged , Office Visits , Randomized Controlled Trials as Topic , Reproducibility of Results , Research , Risk Factors , United States , Valine/therapeutic use , Valsartan
6.
Eur Heart J ; 27(23): 2866-70, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17101637

ABSTRACT

AIMS: Atrial fibrillation (AF) is a risk factor for death in patients with a myocardial infarction, but highly variable results are reported in patients with heart failure. We studied the prognostic impact of AF in heart failure patients with and without ischaemic heart disease. METHODS AND RESULTS: During a period of 2 years, 3587 patients admitted to hospital because of heart failure were included in this study. All patients were examined by echocardiography and the presence of AF was recorded. Follow-up was available for 8 years. Twenty four percent of those discharged alive from hospital had AF. After 4 and 8 years of follow-up, mortality was higher in patients with AF than in patients without, 56 vs. 52% and 77 vs. 73%, respectively. Cox multivariable regression analysis showed a small but significant importance of AF for long-term mortality [hazard ratio (HR) 1.12, 95% confidence limits (CI), 1.02-1.23, P=0.018]. There was a significant interaction between the importance of AF and the presence of ischaemic heart disease (P=0.034). In patients with AF at the time of discharge and ischaemic heart disease, HR was 1.25 (95% CI: 1.09-1.42) and P<0.001; in patients with AF at discharge and without ischaemic heart disease, HR was 1.01 (95% CI: 0.88-1.16) and P=0.88. CONCLUSION: AF is associated with increased risk of death only in patients with ischaemic heart disease. This finding may explain the variable results of studies of the prognosis associated with AF in heart failure.


Subject(s)
Atrial Fibrillation/mortality , Heart Failure/mortality , Myocardial Ischemia/mortality , Aged , Aged, 80 and over , Denmark/epidemiology , Female , Hospital Mortality , Humans , Male , Middle Aged , Prognosis , Regression Analysis , Risk Factors
7.
Nature ; 433(7023): 286-9, 2005 Jan 20.
Article in English | MEDLINE | ID: mdl-15662417

ABSTRACT

Mass is the most fundamental parameter of a star, yet it is also one of the most difficult to measure directly. In general, astronomers estimate stellar masses by determining the luminosity and using the 'mass-luminosity' relationship, but this relationship has never been accurately calibrated for young, low-mass stars and brown dwarfs. Masses for these low-mass objects are therefore constrained only by theoretical models. A new high-contrast adaptive optics camera enabled the discovery of a young (50 million years) companion only 0.156 arcseconds (2.3 au) from the more luminous (> 120 times brighter) star AB Doradus A. Here we report a dynamical determination of the mass of the newly resolved low-mass companion AB Dor C, whose mass is 0.090 +/- 0.005 solar masses. Given its measured 1-2-micrometre luminosity, we have found that the standard mass-luminosity relations overestimate the near-infrared luminosity of such objects by about a factor of approximately 2.5 at young ages. The young, cool objects hitherto thought to be substellar in mass are therefore about twice as massive, which means that the frequency of brown dwarfs and planetary mass objects in young stellar clusters has been overestimated.

8.
J Nematol ; 35(1): 35-8, 2003 Mar.
Article in English | MEDLINE | ID: mdl-19265972

ABSTRACT

Because rapeseed, especially canola, has the potential to be grown in rotation with sugarbeet in the north-central region of the United States, this study was initiated to assess its susceptibility to infection by Heterodera schachtii and to develop a screening method for Brassica germplasm. Existing methodology was adapted for growing Brassica juncea, B. napus, B. rapa, Brassica hybrids, and sugarbeet, Beta vulgaris, in H. schachtii-infested soil to count the females that developed on the roots. Cysts on sugarbeet contained a mean of 130 eggs compared with 240 for B. napus, lowest for the Brassica. Viability of eggs produced was assessed in soil planted with Brassica and sugarbeet and infested with with 0, 100, 1,000, 3,000, and 5,000 eggs to count resulting females and cysts. Number of females (y) was related linearly to infestation rate (x) by the regression equations y = 2.82 + 0.07(x) for the Brassica lines (R(2) = 0.79; P < 0.001) and y = 0.43 + 0.04(x) for sugarbeet (R(2) = 0.69; P < 0.007). These data indicated the potential for H. schachtii population increase if the two crops are used in rotation. All of the 111 germplasm lines tested were susceptible. The methodology developed during this research would benefit attempts to develop rapeseed cultivars resistant to H. schachtii.

9.
New Phytol ; 119(2): 299-305, 1991 Oct.
Article in English | MEDLINE | ID: mdl-33874142

ABSTRACT

Previous field studies of recruitment in Pastinaca sativa L. indicate that more seedlings from small seeds than from large seeds survive short-term droughts. To explore this phenomenon, the effects of variation in seed biomass in Pastinaca sativa on embryo size and seedling characteristics 10, 20, 30 and 40 days after emergence were investigated. On the basis of most characteristics, seedlings from large seeds should be superior to seedlings from small seeds. Embryo length and cotyledon area were positively related to seed biomass, as were above ground biomass, total leaf area, and root biomass in all harvests. Total seedling biomass was positively related to seed biomass in the 10, 20, and 30 day harvests, but not the 40 day harvest. However, the ratio of maximum root length/total leaf area was negatively related to seed biomass in the 10 and 20 day harvests, suggesting that, under drought conditions, seedlings from small seeds may transpire less water than those from large seeds relative to their ability to reach water supplies. Although seedlings from larger seeds had greater root biomass, this may be of little advantage under drought conditions since approximately 90% of the root biomass is in the upper 10 cm of soil which dries out quickly. The advantage that seedlings from small seeds have under drought conditions is short-lived, lasting about 20 days in the glasshouse and an estimated 60-90 days in the field. This advantage is short-term because the relationship between seed biomass and resource allocation patterns changes during early seedling development.

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