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Rapid Evaluation (rapid + evaluation)
Selected AbstractsA Hand-Carried Personal Ultrasound Device for Rapid Evaluation of Left Ventricular Function: Use After Limited Echo TrainingECHOCARDIOGRAPHY, Issue 4 2003Kristina Lemola A hand-carried personal ultrasound device (HCPUD) may be used for rapid cardiac screening by physicians with limited echo training. Our objective was to determine the accuracy of rapid HCPUD evaluation of left ventricular (LV) size and function when used by a Cardiology Fellow. Forty-five patients underwent an HCPUD exam using a 2.4-kg device with a 2- to 4-MHz curved transducer and color power Doppler (SonoSite). The results were compared with sonographer-performed and echocardiographer-interpreted exams using conventional equipment. The HCPUD exam lasted 6 ± 2 minutes. There was 100% agreement between HCPUD and conventional echo on qualitative assessment of LV systolic function. Comparing the HCPUD and conventional linear measurements of left ventricular end-diastolic dimension (LVEDD) and of interventricular septal (IVS) thickness: LVEDD is HCPUD = 0.94 conventional ,0.2,r = 0.82, P < 0.0001; IVS is HCPUD= 0.59conventional+0.6, r = 0.69, P < 0.0001. Thus, an HCPUD can effectively be used after limited training to rapidly screen for qualitative abnormalities of LV systolic function. Quantitative measurements of smaller structures with the HCPUD are more challenging. (ECHOCARDIOGRAPHY, Volume 20, May 2003) [source] VMAT2 quantitation by PET as a biomarker for ,-cell mass in health and diseaseDIABETES OBESITY & METABOLISM, Issue 2008M. Freeby The common pathology underlying both type 1 and type 2 diabetes (T1DM and T2DM) is insufficient ,-cell mass (BCM) to meet metabolic demands. An important impediment to the more rapid evaluation of interventions for both T1DM and T2DM lack of biomarkers of pancreatic BCM. A reliable means of monitoring the mass and/or function of ,-cells would enable evaluation of the progression of diabetes as well as the monitoring of pharmacologic and other interventions. Recently, we identified a biomarker of BCM that is quantifiable by positron emission tomography (PET). PET is an imaging technique which allows for non-invasive measurements of radioligand uptake and clearance, is sensitive in the pico- to nanomolar range and of which the results can be deconvoluted into measurements of receptor concentration. For BCM estimates, we have identified VMAT2 (vesicular monoamine transporter type 2) as a biomarker and [11C] DTBZ (dihydrotetrabenazine) as the transporter's ligand. VMAT2 is highly expressed in ,-cells of the human pancreas relative to other cells of the endocrine and exocrine pancreas. Thus measurements of [11C] DTBZ in the pancreas provide an indirect measurement of BCM. Here we summarize our ongoing efforts to validate the clinical utility of this non-invasive approach to real-time BCM measurements [source] The S and G transformations for computing three-center nuclear attraction integralsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 8 2009Richard Mikael Slevinsky Abstract It is now well established that nonlinear transformations can be extremely useful in the case of oscillatory integrals. In previous work, we could show that the G transformation, which is not so well known among those interested in the numerical evaluation of highly oscillatory integrals, works very well for the extremely challenging integral called Twisted Tail. In this work, we demonstrate that these techniques also apply to three-center nuclear attraction integrals over exponential type functions. The accurate and rapid evaluation of these integrals is required in ab initio molecular structure calculations and density functional theory. Using a basis set of B functions and profiting from their relatively simple Fourier representation, these integrals are formulated as analytical expressions involving highly oscillatory spherical Bessel integral functions. In the present work, we implement two highly accurate algorithms for three-center nuclear attraction integrals. The first algorithm is based on the G transformation and the second is based on a combination of the S and G transformations. The application of these transformations is largely due to the properties of special functions that allow the computation of higher order derivatives of the integrands with exceptional simplicity. The numerical results illustrate the accuracy of these algorithms applied to three-center nuclear attraction integrals over exponential type functions with a miscellany of different parameters. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] A comparison of management options for leatherjacket populations in organic crop rotations using mathematical modelsAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2009Rod P. Blackshaw Abstract 1,Pest management in organic systems is challenged by the paucity of options for direct interventions to control damaging populations compared with conventional agriculture. Consequently, a greater emphasis has to be placed on managing pest numbers through a rotation. In the present study, simulation modelling is used to evaluate the effects of different management options on populations of Tipula paludosa (leatherjackets) in organic rotations. 2,The growth of leatherjacket populations in grass was simulated over 5 years for different starting numbers. A significant risk of leatherjacket attack to subsequent crops can be avoided by limiting the fertility building phase of a rotation to a maximum of 2 years. 3,The effect of cultural control through additional cultivation interventions was compared in rotations comprising a grass/clover fertility building phase with host and/or nonhost crops. It is concluded that the effects are marginal and that prophylactic use cannot be recommended. 4,The prophylactic use of biological control agents in permanent grass and grass/arable rotations was investigated. Maximum population reductions in grass were achieved through annual autumn applications but the optimal economic strategy was less frequent than this. Application in the autumn preceding a spring-sown arable crop provided the best risk reduction. 5,A model decision support system for the control of pests in organic systems using data for leatherjacket damage to spring barley is presented. Economic threshold concepts are used to define when cultural control (as additional cultivation) and biocontrol applications should be used. 6,The present study shows the potential benefits of simulation modelling for the rapid evaluation of a wide range of pest management options. Any conclusions drawn from such simulations, however, are provisional until they can be tested experimentally. [source] New algorithms and an in silico benchmark for computational enzyme designPROTEIN SCIENCE, Issue 12 2006Alexandre Zanghellini Abstract The creation of novel enzymes capable of catalyzing any desired chemical reaction is a grand challenge for computational protein design. Here we describe two new algorithms for enzyme design that employ hashing techniques to allow searching through large numbers of protein scaffolds for optimal catalytic site placement. We also describe an in silico benchmark, based on the recapitulation of the active sites of native enzymes, that allows rapid evaluation and testing of enzyme design methodologies. In the benchmark test, which consists of designing sites for each of 10 different chemical reactions in backbone scaffolds derived from 10 enzymes catalyzing the reactions, the new methods succeed in identifying the native site in the native scaffold and ranking it within the top five designs for six of the 10 reactions. The new methods can be directly applied to the design of new enzymes, and the benchmark provides a powerful in silico test for guiding improvements in computational enzyme design. [source] One-year Outcomes Following Coronary Computerized Tomographic Angiography for Evaluation of Emergency Department Patients with Potential Acute Coronary SyndromeACADEMIC EMERGENCY MEDICINE, Issue 8 2009Judd E. Hollander MD Abstract Objectives:, Coronary computerized tomographic angiography (CTA) has high correlation with cardiac catheterization and has been shown to be safe and cost-effective when used for rapid evaluation of low-risk chest pain patients from the emergency department (ED). The long-term outcome of patients discharged from the ED with negative coronary CTA has not been well studied. Methods:, The authors prospectively evaluated consecutive low- to intermediate-risk patients who received coronary CTA in the ED for evaluation of a potential acute coronary syndrome (ACS). Patients with cocaine use, known cancer, and significant comorbidity reducing life expectancy and those found to have significant disease (stenosis , 50% or ejection fraction < 30%) were excluded. Demographics, medical and cardiac history, labs, and electrocardiogram (ECG) results were collected. Patients were followed by telephone contact and record review for 1 year. The main outcome was 1-year cardiovascular death or nonfatal acute myocardial infarction (AMI). Results:, Of 588 patients who received coronary CTA in the ED, 481 met study criteria. They had a mean (±SD) age of 46.1 (±8.8) years, 63% were black or African American, and 60% were female. There were 53 patients (11%) rehospitalized and 51 patients (11%) who received further diagnostic testing (stress or catheterization) over the subsequent year. There was one death (0.2%; 95% confidence interval [CI] = 0.01% to 1.15%) with unclear etiology, no AMI (0%; 95% CI = 0 to 0.76%), and no revascularization procedures (0%; 95% CI = 0 to 0.76%) during this time period. Conclusions:, Low- to intermediate-risk patients with a Thrombosis In Myocardial Infarction (TIMI) score of 0 to 2 who present to the ED with potential ACS and have a negative coronary CTA have a very low likelihood of cardiovascular events over the ensuing year. [source] Increasing Length of Stay Among Adult Visits to U.S. Emergency Departments, 2001,2005ACADEMIC EMERGENCY MEDICINE, Issue 7 2009Andrew Herring MD Abstract Background:, Emergency departments (EDs) are traditionally designed to provide rapid evaluation and stabilization and are neither staffed nor equipped to provide prolonged care. Longer ED length of stay (LOS) may compromise quality of care and contribute to delays in the emergency evaluation of other patients. Objectives:, The objective was to determine whether ED LOS increased between 2001 and 2005 and whether trends varied by patient and hospital factors. Methods:, This was a retrospective analysis of a nationally representative sample of 138,569 adult ED visits from the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2001 to 2005. ED LOS was measured from registration to discharge. Results:, Median ED LOS increased 3.5% per year from 132 minutes in 2001 to 154 minutes in 2005 (p-value for trend < 0.001). There was a larger increase among critically ill patients for whom ED LOS increased 7.0% annually from 185 minutes in 2001 to 254 minutes in 2005 (p-value for trend < 0.01). ED LOS was persistently longer for black/African American, non-Hispanic patients (10.6% longer) and Hispanic patients (13.9% longer) than for non-Hispanic white patients, and these differences did not diminish over time. Among factors potentially associated with increasing ED LOS, a large increase was found (60.1%, p-value for trend < 0.001) in the use of advanced diagnostic imaging (computed tomography [CT], magnetic resonance imaging [MR], and ultrasound [US]) and in the proportion of ED visits at which five or more diagnostic or screening tests were ordered (17.6% increase, p-value for trend = 0.001). The proportion of uninsured patients was stable throughout the study period, and EDs with predominately privately insured patients experienced significant increases in ED LOS (4.0% per year from 2001 to 2005, p-value for trend < 0.01). Conclusions:, Emergency department LOS in the United States is increasing, especially for critically ill patients for whom time-sensitive interventions are most important. The disparity of longer ED LOS for African Americans and Hispanics is not improving. [source] High-speed crystal detection and characterization using a fast-readout detectorACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2010Jun Aishima A novel raster-scanning method combining continuous sample translation with the fast readout of a Pilatus P6M detector has been developed on microfocus beamline I24 at Diamond Light Source. This fast grid-scan tool allows the rapid evaluation of large sample volumes without the need to increase the beam size at the sample through changes in beamline hardware. A slow version is available for slow-readout detectors. Examples of grid-scan use in centring optically invisible samples and in detecting and characterizing numerous microcrystals on a mesh-like holder illustrate the most common applications of the grid scan now in routine use on I24. [source] Rapid chain tracing of polypeptide backbones in electron-density mapsACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2010Thomas C. Terwilliger A method for the rapid tracing of polypeptide backbones has been developed. The method creates an approximate chain tracing that is useful for visual evaluation of whether a structure has been solved and for use in scoring the quality of electron-density maps. The essence of the method is to (i) sample candidate C, positions at spacings of approximately 0.6,Å along ridgelines of high electron density, (ii) list all possible nonapeptides that satisfy simple geometric and density criteria using these candidate C, positions, (iii) score the nonapeptides and choose the highest scoring ones, and (iv) find the longest chains that can be made by connecting nonamers. An indexing and storage scheme that allows a single calculation of most distances and density values is used to speed up the process. The method was applied to 42 density-modified electron-density maps at resolutions from 1.5 to 3.8,Å. A total of 21,428 residues in these maps were traced in 24 CPU min with an overall r.m.s.d. of 1.61,Å for C, atoms compared with the known refined structures. The method appears to be suitable for rapid evaluation of electron-density map quality. [source] Geriatric Emergency Medicine Educational Module: Abdominal Pain in the Older AdultACADEMIC EMERGENCY MEDICINE, Issue 2009Lowell Gerson The Society for Emergency Medicine (SAEM) Geriatrics Task Force has created an instructional tool to address the complaint of abdominal pain in older adults presenting to the emergency department (ED). This is the first module in a comprehensive, web-based geriatric emergency medicine curriculum that will address common syndromes in older adults presenting to the ED. There is no formal, residency-based curriculum in geriatric emergency medicine and there is a paucity of geriatric Continuing Medical Education (CME) opportunities for practicing emergency physicians. The amount, quality, and convenience of geriatrics training available to emergency physicians is insufficient. This educational gap is particularly concerning given the ever-growing volume of older adult emergency patients. The Task Force chose to focus first on geriatric abdominal pain because a survey of emergency physicians in the mid 1990s found that it is one of the most difficult complaints to evaluate and manage. The module comprises of six clinical cases with a pre- and post-test. Together, these cases encompass the broad differential diagnosis for geriatric abdominal pain and the core medical knowledge pertaining to the subject. The modules will expose the learner, through either content or modeling, to the six Accreditation Council for Graduate Medical Education (ACGME) core competencies and to the Principles of Geriatric Emergency Medicine including rapid evaluation of functional status, communication skills, and consideration of the effect of polypharmacy and co-morbidity on the presenting complaint. This module will be available to residency programs as an "asynchronous educational session" via the Council of Emergency Medicine Residency Directors (CORD) website as well as to practicing emergency physicians via the SAEM and American College of Emergency Physicians (ACEP) websites. [source] | |||||||||||||