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Increased Volume (increased + volume)
Selected AbstractsIncreased volume of coverage for abdominal contrast-enhanced MR angiography with two-dimensional autocalibrating parallel imaging: Initial experience at 3.0 TeslaJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2009Darren P. Lum MD Abstract Purpose: To assess the feasibility and the quality of abdominal three-dimensional (3D) contrast enhanced MR angiograms acquired at 3.0 Tesla (T) using a new 2D-accelerated autocalibrating parallel reconstruction method for Cartesian sampling (2D-ARC). Materials and Methods: With institutional review board approval and written informed consent, a prospective trial in 6 normal healthy volunteers and 23 patients referred for evaluation of suspected renovascular disease was performed. The volunteers underwent abdominal MRA with and without 2D-ARC acceleration. Images were evaluated independently by two blinded vascular radiologists in randomized order. Vessel conspicuity was rated on a five-point scale. Evaluation for significant differences between the scores for each technique was performed using a Wilcoxon signed-rank test. Results: In the series of six volunteers, no statistical significance was found between the image quality scores for 2D-ARC accelerated and nonaccelerated exams. A high proportion of the 23 clinical 2D-ARC exams were graded as diagnostic (vessel conspicuity score ,2; Reader 1, 96%; Reader 2, 100%) for overall image quality. Conclusion: Subjective image quality of 2D-ARC accelerated MRA was equivalent to the conventional MRA method. However, the 2D-ARC accelerated sequence provided a 3.5-fold increase in imaging volume, complete abdominal coverage, and a 30% reduction in voxel volume, all within the same acquisition time. J. Magn. Reson. Imaging 2009;30:1093,1100. © 2009 Wiley-Liss, Inc. [source] Swedish healthcare under pressureHEALTH ECONOMICS, Issue S1 2005Anders Anell Abstract Swedish healthcare, run by local governments at both the regional (county) and the municipal levels, has been under pressure during the last 15 years, following increased scrutiny of performance and demand for cost-containment. Health-care expenditures per capita and levels of resource inputs have grown, but more slowly than in other EU countries. At the same time, the number of elderly people has increased, as have options for medical treatment. In the late 1980s, several local governments referred to long waiting-lists for elective treatment and anecdotal evidence of inefficiency and poor responsiveness when arguing for market-oriented reforms. A purchaser,provider split followed, and so did changes in the payment systems for health-care providers. According to the available evidence, these reforms yielded an increased volume of services in the short run; but traditional hierarchical management soon replaced the new incentives. Moreover, evidence suggests that changes introduced by the national government, and the deteriorating funding conditions together with a continued use of new medical technology, have had more far-reaching effects on health-care output and outcome than local-government reforms. Copyright © 2005 John Wiley & Sons, Ltd. [source] Short/long heterozygotes at 5HTTLPR and white matter lesions in geriatric depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 3 2008David C. Steffens Abstract Objective We examined the relationship between 5HTTLPR genotype and volume of magnetic resonance imaging (MRI) brain lesions. Method We studied 217 older depressed patients and 141 individuals in the comparison group using a standard brain MRI protocol to calculate lesion volumes. Genotype at 5HTTLPR was determined for each subject. Results In age-adjusted models, the l/s genotype was associated with increased volume of total and white-matter lesions among depressed patients. This relationship lost significance in models controlling for reported hypertension. Conclusions The finding that 5HTTLPR heterozygotes have higher vascular lesion volumes may be related to development of hypertension. Copyright © 2007 John Wiley & Sons, Ltd. [source] Material civilization: things and societyTHE BRITISH JOURNAL OF SOCIOLOGY, Issue 2 2006Tim Dant Abstract This paper argues that although classical sociology has largely overlooked the importance of social relations with the material world in shaping the form of society, Braudel's concept of ,material civilization' is a useful way to begin to understand the sociological significance of this relationship. The limitations of Braudel's historical and general concept can be partially overcome with Elias's analysis of the connection between ,technization' and ,civilization' that allows for both a civilizing and a de-civilizing impact of emergent forms of material relation that both lengthen and shorten the chains of interdependence between the members of a society. It is suggested that the concept of the ,morality of things' employed by a number of commentators is useful in summarizing the civilizing effects of material objects and addressing their sociological significance. From the sociology of consumption the idea of materiality as a sign of social relationships can be drawn, and from the sociology of technology the idea of socio-technical systems and actor-networks can contribute to the understanding of material civilization. It is argued that the concept of ,material capital' can usefully summarize the variable social value of objects but to understand the complexity of material civilization as it unfolds in everyday life, an analysis of ,material interaction' is needed. Finally the paper suggests some initial themes and issues apparent in contemporary society that the sociological study of material civilization might address; the increased volume, functional complexity and material specificity of objects and the increased social complexity, autonomy and substitutability that is entailed. A theory of ,material civilization' is the first step in establishing a sociology of objects. [source] Getting Out Early: An Analysis of Market Making Activity at the Recommending Analyst's FirmTHE JOURNAL OF FINANCE, Issue 5 2009JENNIFER L. JUERGENS ABSTRACT This paper examines trading volume for Nasdaq market makers around analyst recommendation changes issued by an analyst at the same firm. Using Nasdaq PostData, we find a disproportionate increase in market making volume associated with the firm's recommendation changes and evidence of elevated sell volume at the recommending analyst's firm in the 2 days preceding a downgrade. The implications are that the information source matters in determining the placement of trades and that the issuing analyst's firm appears to be rewarded for prereleasing information through increased volume. These findings constitute new evidence of compensation for research production through the market making channel. [source] Development of a simultaneous liquid,liquid extraction and chiral derivatization method for stereospecific GC-MS analysis of amphetamine-type stimulants in human urine using fractional factorial designBIOMEDICAL CHROMATOGRAPHY, Issue 9 2008W. R. Wan Aasim Abstract A stereospecific gas chromatography,mass spectrometry analysis method for amphetamine-type stimulants in human urine was recently developed. For maximum efficiency, liquid,liquid extraction and chiral derivatization of the analytes using (R)-(,)- , -methoxy- , -(trifluoromethyl)phenylacetyl chloride were performed simultaneously. The effects of (1) use of saturated sodium chloride in 2.0 m sodium hydroxide, (2) extraction solvent volume, (3) percentage of triethylamine, (4) derivatization reagent volume, (5) sample mixing time, (6) incubation temperature and (7) incubation time on method sensitivity and variability were assessed using a two-level, eight-run Plackett,Burman design followed by a fold-over design. The use of saturated sodium chloride solution and the derivatization reagent volume were significant factors (ANOVA, p < 0.01). The saturated sodium chloride solution decreased sensitivity whereas an increased volume of derivatization reagent increased sensitivity. Calibration curves for all analytes were linear between 5 and 500 µg/L, with correlation coefficients of >0.99. Detection limits were ,2.3 µg/L and quantitation limits ,7.7 µg/L. Reproducibility was good, with relative standard deviation values at <20%. Recovery exceeded 100% for most analytes. The experimental design enabled easy and rapid identification of significant factors using a minimal number of samples. This method has good potential for studies requiring rapid and sensitive stereospecific quantification of amphetamine-type stimulants. Copyright © 2008 John Wiley & Sons, Ltd. [source] The Epidemiology of Emergency Medical Services Use by Older Adults: An Analysis of the National Hospital Ambulatory Medical Care SurveyACADEMIC EMERGENCY MEDICINE, Issue 5 2007Manish N. Shah MD ObjectivesTo characterize older adult emergency department (ED) visits arriving by emergency medical services (EMS) and to identify factors associated with those patient visits. MethodsA secondary analysis of the ED component of the 1997,2000 National Hospital Ambulatory Medical Care Survey using logistic regression analyses was conducted. The dependent variable was the modes of arrival (EMS vs. not EMS) to the ED. Independent variables were grouped into four domains: demographic, clinical, system, and service characteristics. ResultsBetween 1997 and 2000, 38% of EMS responses were for patients aged 65 years and older. During that period, 62.2 million older adult ED patient visits occurred; 38% arrived via EMS. The average rate of EMS utilization by older adults was 167/1,000 population per year, more than four times the rate for younger patients (39/1,000 population). Fifty-three percent of EMS responses with transport to an ED for older adults resulted in hospital admission. Factors found to be associated with EMS mode of arrival included demographic (older age and urban residence), clinical (need for more rapid care and circulatory system illnesses), and service (need for procedures). ConclusionsOlder adults account for a large proportion of EMS responses and use EMS at a disproportionately high rate. As the older adult population grows, EMS systems must prepare for the increased volume of older adults by making changes in training, operations, and equipment. [source] Hypervolaemia improves global and local function and efficiency in postischaemic myocardiumCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2001FY Du SUMMARY 1. In the present study, we investigated the effects of blood volume on postischaemic function and efficiency. In 14 anaesthetized dogs, following recovery from a period of 15 min occlusion of the left anterior descending coronary artery, the effects of hypervolaemia (HYPER; 15% increased volume produced by fast infusion of Hespan; B Braun Medical, Irvine, CA, USA), normovolaemia (NORMO) and hypovolaemia (HYPO) were studied. 2. Although myocardial O2 consumption was not significantly increased by volume (6.37±0.94 vs 6.89±1.1 mL/min per 100 g for HYPO and HYPER, respectively), local work of the stunned myocardium was markedly elevated (8.8±1.7 vs 22.5±3.5 g·mm/ beat, for HYPO and HYPER, respectively; P < 0.05). External work of the heart was also significantly improved (71.8±12.7 vs 139.5±16.2 mmHg·L/min for HYPO and HYPER, respectively). These data indicate markedly improved efficiency produced by volume, because work was increased with no change in myocardial O2 consumption. 3. Local dysfunction was characterized by several parameters, including systolic bulge, end-diastolic length, delay to onset of shortening, end shortening time delay (EST) and tail work ratio. Hypervolaemia reduced EST compared with hypovolaemia (98.6±18.3 vs 110.7±14.9 msec, respectively; P < 0.05) and improved tail work ratio (28.0±7.0 vs 36.0±7.0%, respectively; P < 0.05), with no effects on systolic bulge, end-diastolic length and delay to onset of shortening. 4. Thus, even in the postischaemic myocardium, increasing work by volume is energetically efficient and is accompanied by partial improvement of local dysfunction. [source] Single Implants and Buccal Bone Grafts in the Anterior Maxilla: Measurements of Buccal Crestal Contours in a 6-Year Prospective Clinical StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2005Odont Dr/PhD, Torsten Jemt DDS ABSTRACT Background: Patients provided with buccal bone grafts seem to lose a substantial part of the graft in the short term. Purpose: To measure long-term changes in buccal and proximal tissue volumes after local bone grafting and single implant treatment. Materials and Methods: Eight of 10 originally treated male patients were followed up for 6 years after treatment with buccal bone grafts in the central incisor region. After a healing time of 6 months, a two-stage implant surgery procedure was performed followed by single crown placement. Clinical photographs and impressions were taken prior to the surgical interventions and after crown placement and at first and fifth annual checkups. The photographs were analyzed with regard to papilla regeneration by means of a clinical papilla index. The models were used to measure the clinical length of teeth and tooth movements adjacent to the implants. Changes in buccal crest volume during the study period were measured by means of optical scanning of obtained study models. Results: Papillae volume increased significantly (p < .05) during the first year, thereafter showing a slow further increase during the 4 following years. Three of the patients (38%) presented small movements of their adjacent central incisor in a vertical or palatal direction of less than 1 mm during the follow-up period. All patients showed resorption during the first year after grafting (p < .01), in which three patients (38%) had lost basically all of increased volume at second surgery. After abutment or crown placement, all patients showed an increased volume (p < .01), followed by an average reduction during the first year, reaching a significant level in the apical part of the crest (p < .05). Thereafter, a relatively stable average situation was observed during the following 4 years, with individual variations, however. Conclusion: Local bone grafting seems to create sufficient bone volume for implant placement after 6 months, but individual variations in resorption pattern make the grafting procedure unpredictable for long-term prognosis. Instead, the abutment and the crown seem to play a more important role for building up and maintaining the buccal contour in the coronal part of the crest long term. [source] | ||||||||||