61 research outputs found
Mud In His Ears
Illustration of a man\u27s head hovering over a jeep style vehicle.https://scholarsjunction.msstate.edu/cht-sheet-music/2557/thumbnail.jp
Absolute photoionization cross section measurements of the Kr I-isoelectronic sequence
Photoionization spectra have been recorded in the 4s, 4p and 3d resonance regions for the Kr Iisoelectronic sequence using both the dual laser produced plasma technique (at DCU) to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique (at ASTRID) to measure absolute photoionization cross sections. Profile parameters are compared for the 4s − np resonances of Rb+ and Sr2+. Many new 4p " ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb+ and Sr2+ ions show preferential decay via double photoionization. This is only the second report where both the DLP technique and the merged beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques (i.e. better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged beam technique) are highlighted
Modelling of impaired cerebral blood flow due to gaseous emboli
Bubbles introduced to the arterial circulation during invasive medical
procedures can have devastating consequences for brain function but their
effects are currently difficult to quantify. Here we present a Monte-Carlo
simulation investigating the impact of gas bubbles on cerebral blood flow. For
the first time, this model includes realistic adhesion forces, bubble
deformation, fluid dynamical considerations, and bubble dissolution. This
allows investigation of the effects of buoyancy, solubility, and blood pressure
on embolus clearance.
Our results illustrate that blockages depend on several factors, including
the number and size distribution of incident emboli, dissolution time and blood
pressure. We found it essential to model the deformation of bubbles to avoid
overestimation of arterial obstruction. Incorporation of buoyancy effects
within our model slightly reduced the overall level of obstruction but did not
decrease embolus clearance times. We found that higher blood pressures generate
lower levels of obstruction and improve embolus clearance. Finally, we
demonstrate the effects of gas solubility and discuss potential clinical
applications of the model
Perioperative Cerebral Microbleeds After Adult Cardiac Surgery.
Background and Purpose- Cerebral microbleeds (CMBs) have been observed using magnetic resonance imaging in patients with cardiovascular risk factors, cognitive deterioration, small vessel disease, and dementia. They are a well-known consequence of cerebral amyloid angiopathy, chronic hypertension, and diffuse axonal injury, among other causes. However, the frequency and location of new CMBs postadult cardiac surgery, in association with cognition and perioperative risk factors, have yet to be studied. Methods- Pre- and postsurgery magnetic resonance susceptibility-weighted images and neuropsychological tests were analyzed from a total of 75 patients undergoing cardiac surgery (70 men; mean age, 63±10 years). CMBs were identified by a neuroradiologist blinded to clinical details who independently assessed the presence and location of CMBs using standardized criteria. Results- New CMBs were identified in 76% of patients after cardiac surgery. The majority of new CMBs were located in the frontal lobe (46%) followed by the parietal lobe (15%), cerebellum (13%), occipital lobe (12%), and temporal lobe (8%). Patients with new CMBs typically began with a higher prevalence of preexisting CMBs ( P=0.02). New CMBs were associated with longer cardiopulmonary bypass times ( P=0.003), and there was a borderline association with lower percentage hematocrit ( P=0.04). Logistic regression analysis suggested a ≈2% increase in the odds of acquiring new CMBs during cardiac surgery for every minute of bypass time (odds ratio, 1.02; 95% CI, 1.00-1.05; P=0.04). Postoperative neuropsychological decline was observed in 44% of patients and seemed to be unrelated to new CMBs. Conclusions- New CMBs identified using susceptibility-weighted images were found in 76% of patients who underwent cardiac surgery. CMBs were globally distributed with the highest numbers in the frontal and parietal lobes. Our regression analysis indicated that length of cardiopulmonary bypass time and lowered hematocrit may be significant predictors for new CMBs after cardiac surgery. Clinical Trial Registration- URL: http://www.isrctn.com . Unique identifier: 66022965
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Neurological impact of emboli during adult cardiac surgery.
OBJECTIVES: This study draws on advances in Doppler ultrasound bubble sizing to investigate whether high volumes of macro-bubbles entering the brain during cardiac surgery increase the risk of new cerebral microbleeds (CMBs), ischemic MR lesions, or post-operative cognitive decline (POCD). METHODS: Transcranial Doppler (TCD) ultrasound recordings were analysed to estimate numbers of emboli and macrobubbles (>100 μm) entering the brain during cardiac surgery. Logistic regression was used to explore the hypothesis that emboli characteristics affect the incidence of new brain injuries identified through pre- and post-operative MRI and neuropsychological testing. RESULTS: TCD, MRI, and neuropsychological test data were compared between 28 valve and 18 CABG patients. Although valve patients received over twice as many emboli per procedure [median: 1995 vs. 859, p = .004], and seven times as many macro-bubbles [median: 218 vs. 28, p = .001], high volumes of macrobubbles were not found to be significantly associated with new CMBs, new ischaemic lesions, or POCD. The odds of acquiring new CMBs increased by approximately 5% [95% CI: 1 to 10%] for every embolus detected in the first minute after the release of the aortic cross-clamp (AxC). Logistic regression models also confirmed previous findings that cardiopulmonary bypass time and valve surgery were significant predictors for new CMBs (both p = .03). Logistic regression analysis estimated an increase in the odds of acquiring new CMBs of 6% [95% CI: 1 to 12%] for every minute of bypass time over 91 mins. CONCLUSIONS: This small study provides new information about the properties and numbers of bubbles entering the brain during surgery, but found no evidence to substantiate a direct link between large numbers of macrobubbles and adverse cognitive or MR outcome. Clinical Trial Registration URL - http://www.isrctn.com. Unique identifier: 66022965
What’s in a Name? Use of Brand versus Generic Drug Names in United States Outpatient Practice
BACKGROUND: The use of brand rather than generic names for medications can increase health care costs. However, little is known at a national level about how often physicians refer to drugs using their brand or generic names. OBJECTIVE: To evaluate how often physicians refer to drugs using brand or generic terminology. DESIGN AND PARTICIPANTS: We used data from the 2003 National Ambulatory Medical Care Survey (NAMCS), a nationally representative survey of 25,288 community-based outpatient visits in the United States. After each visit, patient medications were recorded on a survey encounter form by the treating physician or transcribed from office notes. MEASUREMENTS: Our main outcome measure was the frequency with which medications were recorded on the encounter form using their brand or generic names. RESULTS: For 20 commonly used drugs, the median frequency of brand name use was 98% (interquartile range, 81–100%). Among 12 medications with no generic competition at the time of the survey, the median frequency of brand name use was 100% (range 92–100%). Among 8 medications with generic competition at the time of the survey (“multisource” drugs), the median frequency of brand name use was 79% (range 0–98%; P < .001 for difference between drugs with and without generic competition). CONCLUSIONS: Physicians refer to most medications by their brand names, including drugs with generic formulations. This may lead to higher health care costs by promoting the use of brand-name products when generic alternatives are available
Report of Third Annual Seminar on Estate Planning
Reports from the UK/CLE Third Annual Seminar on Estate Planning held July 23-24, 1976
Measuring patient-perceived continuity of care for patients with long-term conditions in primary care
Background: Continuity of care is widely acknowledged as important for patients with multi-morbidity but simple, service-orientated indices cannot capture the full impact of continuity in complex care delivery systems. The patient's perspective is important to assess outcomes fully and this is challenging because generic measures of patient-perceived continuity are lacking. We investigate the Chao Perception of Continuity (Chao PC) scale to determine its suitability as a measure of continuity of care for patients with a long-term condition (stroke), and co-morbidity, in a primary care setting. Methods: Design and Setting: A questionnaire study embedded in a prospective observational cohort study of outcomes for patients following acute stroke. Participants: 168 community dwelling patients (58% male) mean age 68 years a minimum one year post-stroke. Functional status: Barthel Index mean =16. Intervention: A 23-item questionnaire, the Chao Perception of Continuity (Chao PC) scale, sent by post to their place of residence or administered face to face as part of the final cohort study assessment. Results: 310 patients were invited to participate; 168 (54%) completed a questionnaire. All 23 questionnaire items were entered into a Principal Component Analysis. Emergent factors from the exploratory analysis were (1) inter-personal trust (relational continuity); (2) interpersonal knowledge and information (informational and relational continuity) and (3) the process of care (managerial continuity). The strongest of these was inter-personal trust. Conclusion: The context-specific items in the Chao PC scale are difficult for respondents to interpret in a United Kingdom Primary Care setting resulting in missing data and low response rates. The Chao-PC therefore cannot be recommended for wider application as a general measure of continuity of care without significant modification. Our findings reflect the acknowledged dimensions of continuity and support the concept of continuity of care as a multi-dimensional construct. We demonstrate the overlapping boundaries across the dimensions in the factor structure derived. Trust and interpersonal knowledge are clearly identified as valuable components of any patient-perceived measure of continuity of care
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