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11.
Raphaëlle Savoire Jean‐Louis Lanoisellé Hélène Ducatel Eugène Vorobiev 《European Journal of Lipid Science and Technology》2008,110(8):725-734
Seven linseed varieties were harvested at seven times before complete maturity. Microscale oilseed expressions were subsequently carried out on it. A pressure of 10 MPa was applied for 1 h under uniaxial stress. The results were characterized in terms of oil, water and mucilage content, harvest date and oil yield. The piston displacement versus time (creep curves) was described by a four‐Kelvin‐Voigt elements viscoelastic model. Parameters were derived from the model, such as the mechanical properties of seeds (compressibility moduli), showing that the viscoelastic model fits well the experimental data (R² ≈ 0.999). The modeling parameters were combined with some biochemical data in order to predict the kinetics of oil extraction. 相似文献
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EJ Amella 《Canadian Metallurgical Quarterly》1998,19(5):269-74; quiz 275
Adequate nutritional intake is critical to preserving the health of older people. When an elderly person requires assistance with eating, the most social of all activities of daily living, the assessment of nutritional issues becomes multidimensional and interdisciplinary. Management strategies should involve the professional nurse's attention to dietary needs, as well as the social, cultural, and interactive components of mealtime. Additionally, special strategies need to be developed for people with cognitive and physical disabilities. 相似文献
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CB Granger J Hirsch RM Califf J Col HD White A Betriu LH Woodlief KL Lee EG Bovill RJ Simes EJ Topol 《Canadian Metallurgical Quarterly》1996,93(5):870-878
BACKGROUND: Although intravenous heparin is commonly used after thrombolytic therapy, few reports have addressed the relationship between the degree of anticoagulation and clinical outcomes. We examined the activated partial thromboplastin time (aPTT) in 29,656 patients in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO-I) trial and analyzed the relationship between the aPTT and both baseline patient characteristics and clinical outcomes. METHODS AND RESULTS: Intravenous heparin was administered as a 5000-U bolus followed by an initial infusion of 1000 U/h, with dose adjustment to achieve a target aPTT of 60 to 85 seconds. aPTTs were collected 6, 12, and 24 hours after thrombolytic administration. Higher aPTT at 24 hours was strongly related to lower patient weight (P < .00001) as well as older age, female sex, and lack of cigarette smoking (all PT< .0001). At 12 hours, the aPTT associated with the lowest 30-day mortality, stroke, and bleeding rates was 50 to 70 seconds. There was an unexpected direct relationship between the aPTT and the risk of subsequent reinfarction. There was a clustering of reinfarction in the first 10 hours after discontinuation of intravenous heparin. CONCLUSIONS: Although the relationship between aPTT and clinical outcome was confounded to some degree by the influence of baseline prognostic characteristics, aPTTs higher than 70 seconds were found to be associated with higher likelihood of mortality, stroke, bleeding, and reinfarction. These findings suggest that until proven otherwise, we should consider the aPTT range of 50 to 70 seconds as optimal with intravenous heparin after thrombolytic therapy. 相似文献
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Sensors, mounted on the dexterous end of a robot, can be used for feedback control or calibration. When you mount a sensor on a robot it becomes necessary to find the pose (orientation and position) of the sensor relative to the robot. This is the sensor registration problem. Many researchers have provided closed-form solutions to the sensor registration problem; however, the published solutions apply only to sensors that can measure a complete pose (three positions and three orientations). Many sensors, however, can provide only position information; they cannot measure the orientation of an object. This article provides a closed-form solution to the sensor registration problem applicable when: (1) the sensor can provide only position information and (2) the robot can move along and rotate about straight lines. © 1994 John Wiley & Sons, Inc. 相似文献
18.
Pharmacologic profile of survivors of acute myocardial infarction at United States academic hospitals 总被引:1,自引:0,他引:1
BG Phillips JM Yim EJ Brown N Bittar TJ Hoon C Celestin PH Vlasses JL Bauman 《Canadian Metallurgical Quarterly》1996,131(5):872-878
Optimal drug therapy for patients with acute myocardial infarction (AMI) is well described in the medical literature. However, data on the actual pharmacologic management of patients surviving AMI at academic hospitals is unavailable. The purpose of this study was to document treatment profiles in 500 patients surviving AMI at 12 academic hospitals in the United States. These profiles were compared with established guidelines and were evaluated for trends. Overall, thrombolytics (streptokinase > or = tissue-type plasminogen activator) were administered in 29% of the patients, with a greater proportion of patients receiving beta-blockers than calcium channel antagonists in the initial 72 hours (61% vs 40%; p < 0.005) and at discharge (51% vs 35%; p < 0.005). Further, women were less likely than men to receive thrombolytic therapy (odds ratio [OR] = 0.61; confidence interval [CI], 0.54 to 0.69) or beta-blocker therapy within the first 72 hours (OR = 0.61; CI, 0.55 to 0.67) or at hospital discharge (OR = 0.53; CI, 0.48 to 0.58). Overall, improvements could still be made in the number of patients who receive thrombolytic and acute and chronic beta-blocker therapies after AMI, particularly in women. Changes in treatment profiles may be a reflection of the publication of large clinical trials. 相似文献
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Plasma and blood lead concentrations, lead absorption, and lead excretion in nonhuman primates 总被引:2,自引:0,他引:2
EJ O''Flaherty MJ Inskip AP Yagminas CA Franklin 《Canadian Metallurgical Quarterly》1996,138(1):121-130
The effects of pH, temperature, block of energy production, calcium/calmodulin, protein phosphorylation, and cytoskeleton-disrupting agents (cytochalasin D, nocodazole) on the integrity of the membrane skeleton were studied in polarized MDCK cells. The intracellular distributions of alpha-fodrin, actin, and ankyrin were monitored by immunofluorescence microscopy. The membrane skeleton, once assembled, seemed to be quite stable; the only factors releasing alpha-fodrin from the lateral walls were the acidification of the cytoplasm and the depletion of extracellular calcium ions. Upon cellular acidification, some actin was also released from its normal location along the lateral walls and was seen in colocalization with alpha-fodrin in the cytoplasm, whereas ankyrin remained associated with the lateral walls. No accumulation of plasma membrane lipids was observed in the cytoplasm of acidified cells, as visualized by TMA-DPH. These results suggest that the linkages between the fodrin-actin complex and its membrane association sites are broken upon acidification. The pH-induced change in alpha-fodrin localization was reversible upon restoring the normal pH. Reassembly of the membrane skeleton, however, required temperatures above +20 degrees C, normal energy production, proper cell-cell contacts, and polymerized actin. Release of alpha-fodrin from the lateral walls to the cytoplasm was also observed upon depletion of extracellular calcium ions. This change was accompanied by the disruption of cell-cell contacts, supporting the role of proper cell-cell contacts in the maintenance of the membrane skeleton polarity. These results suggest that local alterations of the cytoplasmic pH and calcium ion concentration may be important in regulating the integrity of the membrane skeleton. 相似文献
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