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11.
This research study was undertaken to examine the relationship between pulmonary artery blood temperature (regarded as the 'gold standard' measurement for core body temperature), axilla temperature using the Tempa.DOT Ax chemical thermometer and tympanic membrane temperature using the Diatek 9000 InstaTemp thermometer. Sixty adult intensive care patients had their temperatures monitored. A single set of five simultaneous temperatures, i.e. left and right axilla, left and right tympanic membrane (TM), and pulmonary artery (PA) blood were recorded. The mean difference between left and right TM temperatures was 0.58 degree C, and although both were moderately well correlated with PA temperature (r = 0.63 and 0.78, respectively) the mean differences between the two sites were clinically significant (0.85 degree C and 0.94 degree C, respectively). The range of differences between the sites was significant. Plotting limits of agreement showed that both left and right TM temperatures may be up to 1.2 degrees C above or 1.3 degrees C below PA blood temperature: a clinically unacceptable range. In particular, large temperature differences were recorded when patients were lying with one side of their head to a pillow. Fan therapy directed to the head was not found to affect these differences significantly. The mean difference between left and right axilla temperatures was 0.36 degree C, and although both were modestly correlated with PA temperature (r = 0.48 and 0.53, respectively) the mean differences between the two sites were clinically significant (0.47 degree C and 0.50 degree C, respectively). The range of differences between the sites was particularly significant. Plotting limits of agreement showed that both left and right axilla temperatures may be up to 1.2 degrees C above or 1.6 degrees C below PA blood temperature: a clinically unacceptable range. Because the range of temperature differences found between PA blood and the other sites was so great, it is concluded that neither the chemical axilla thermometer nor the tympanic membrane thermometer used in this study are clinically reliable tools for adult intensive care patients. 相似文献
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The precision of velocity coding for moving stimuli of different spatial frequencies was assessed by measuring velocity discrimination thresholds for a 1-c/deg grating paired with a grating whose spatial frequency ranged from 0.25 to 4 c/deg and for grating pairs of the same spatial frequency (0.25, 1, and 4 c/deg). The gratings always moved upward, with velocities ranging from 0.5 to 16 deg/sec. Velocity discrimination was as precise for stimuli that varied in spatial frequency by +/- 2 octaves (0.25 vs. 1 c/deg and 4 vs. 1 c/deg) as for stimuli of the same spatial frequency, for specific ranges of velocity that depended on the spatial and, therefore, the temporal frequencies of the stimuli. Compared with a 1-c/deg grating, the perceived velocity of 4-c/deg gratings was about 1.3 times faster and that of 0.25-c/deg gratings was about 1.3 times slower. Although these perceived velocity biases imply variation of velocity-signal processing among spatial frequency channels, the discrimination results indicate that the motion-sensing system can compare signals across different spatial frequency channels to make fine velocity discrimination within appropriate temporal frequency limits. 相似文献
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Administered the State-Trait Anxiety Inventory for Children to 78 7th graders before and after they completed the Arithmetic subtest of the Wide Range Achievement Test under differential instructions. Results indicate that only instructions for reporting anxiety during the test showed significant increases in state anxiety. Apparently, state anxiety can subside in a matter of a few minutes after cessation of a stressor, thus emphasizing the need for carefully controlled methods for assessing this phenomenon. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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JW Ely KS Berbaum GR Bergus BH Thompson BT Levy MA Graber ER Evans DA Bedell DS Fick 《Canadian Metallurgical Quarterly》1996,43(3):242-248
Percutaneous cardiopulmonary assist devices (PCPS) have become available in interventional cardiology within recent years. These tools offer the opportunity of performing percutaneous transluminal coronary angioplasty (PTCA) in high-risk patients characterized by significant stenoses of several coronary arteries and a poor left ventricular function. It is unclear for which patients PCPS are necessary and which patients will profit by PTCA as compared to coronary artery bypass grafting (CABG). Therefore, the anticipated risk of CABG and of PTCA without assist devices was calculated according to risk scores and compared with our results of assisted PTCA. In addition the long-term survival rate was investigated. In 35 patients (mean 65.5 years of age, 12 females, 23 males), we performed PTCA concomitant with the use of cardiac assist devices. The indications for the use of a cardiac assist device were severely impaired LV function (EF 30% +/- 8.9%) in combination with significant coronary artery disease (2.7 +/- 0.3 vessels) and a significant supply area of the vessel to be dilated. In 6 patients, PCPS was started before coronary angioplasty because of hemodynamic instability. In 21 cases, PCPS was on a standby basis without being connected to the patient's circulation. In 8 patients, a left heart assist device, the 14F-Hemopump, was inserted percutaneously. The patients were analyzed using risk scores of angioplasty and of coronary bypass graft surgery. The calculated risk of hemodynamic compromise during PTCA according to the risk scores was more than 50%. The anticipated risk of a fatal outcome following CABG would have been 19.8%. PTCA was performed on an average of 2.0 coronary arteries per patient and was successful in 85%. We observed a decline in angina pectoris classification (CCS) from 3.5 to 1.6. An average reduction of 1.1 NYHA class was achieved. The in-hospital mortality was 8.6% (3 patients: 1 x sepsis, 1 x early reocclusion, 1 x cerebral embolism). At 24 months follow-up, a re-PTCA was necessary in four cases because of restenosis. In the remainder, NYHA and CCS class were stable during the follow-up period. An additional five patients died during the first year and two patients in the second year. We conclude that PTCA with the use of a cardiac assist device shows favorable short-term results in a subset of patients with extended coronary artery disease and severely impaired LV function who are not suitable for nonsupported PTCA or CABG due to their risk profile. However, the long term results are not satisfying and stress the need for complete revascularisation with CABG once the patient's condition is stabilized by means of supported PTCA. 相似文献
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Oligomeric Composition of Polyols From Fatty Acid Methyl Ester: The Effect of Ring‐Opening Reactants of Epoxide Groups
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Tuan Noor Maznee Tuan Ismail Nor Azowa Ibrahim Mohd Azmil Mohd Noor Seng Soi Hoong Kosheela Devi Poo Palam Shoot Kian Yeong Zainab Idris Christi M. Schiffman Ibrahim Sendijarevic Emilia Abd Malek Norhazlin Zainuddin Vahid Sendijarevic 《Journal of the American Oil Chemists' Society》2018,95(4):509-523
Commercial availability of fatty acid methyl ester (FAME) from palm oil targeted for biodiesel offers a good feedstock for the production of structurally well‐defined polyols for polyurethane applications. The effect of molecular weight (MW), odd and even carbon numbers, and the linear and branched structure reactants used in the ring‐opening reaction of epoxidized fatty acid methyl ester (E‐FAME) on the properties of polyols was investigated. Conversions of E‐FAME to PolyFAME polyols were confirmed by Fourier transform infrared analysis, oxirane oxygen content, and hydroxyl number. Gel permeation chromatography (GPC) calibrated against polyether polyols as a standard and vapor pressure osmometry were used for MW determination. GPC chromatograms of PolyFAME polyols clearly demonstrated the formation of oligomers during ring‐opening reactions. MW, and odd and even carbon numbers in a structure of linear diols and branched diol used in the syntheses of PolyFAME polyols did not have an effect on crystallinity, glass transition, or melt temperatures measured using Differential scanning calorimetry (DSC). PolyFAME polyols ring‐opened with water, methanol, and 1,2‐propanediol contained secondary hydroxyl groups, whereas PolyFAME polyols ring‐opened with linear diols contained a mixture of primary and secondary hydroxyl groups. It was found that the concentration of primary hydroxyl groups increased significantly by increasing the number of carbons from C2 to C3 in the linear diols. The viscosity of PolyFAME polyols also increased with the MW of linear diols used in the E‐FAME ring‐opening reaction. These findings would be beneficial for formulators in choosing the most cost effective polyols for polyurethane formulations. 相似文献
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Oscillatory structure–property correlation in azelate polyols and thermoplastic polyurethanes
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Tuan Noor Maznee Tuan Ismail Nor Azowa Ibrahim Aisa Sendijarevic Ibrahim Sendijarevic Christi M. Schiffman Seng Soi Hoong Mohd Azmil Mohd Noor Kosheela Devi Poo Palam Shoot Kian Yeong Zainab Idris Emilia Abd. Malek Norhazlin Zainuddin Vahid Sendijarevic 《应用聚合物科学杂志》2018,135(19)
Azelate polyols of 2000 g mol?1 have been successfully prepared via esterification of renewable azelaic acid with linear diols containing different number of CH2 repeating units. Structure–property correlation of the azelate polyols had been evaluated in thermoplastic polyurethanes (TPUs). TPUs based on azelate polyols of longer chained linear diols with >4 CH2 repeat units retained higher degrees of crystallinity associated with the polyol soft segment. The ratio of hydrogen bonded urethane in the hard segment to free urethane phase mixed with the soft segment in the TPUs showed a complex oscillating dependence with increased number of CH2 repeating unit in the linear diols of azelate polyols. Correspondingly, static and dynamic properties of TPUs also showed the oscillatory dependence, whereby dynamic properties maximized with odd number of CH2 repeating unit and material strength maximized with even number of CH2 repeating unit. The results therefore can be used as guide to select appropriate azelate polyols to target specific TPU performance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46258. 相似文献
20.
Directional sensitivity of the retina (the Stiles-Crawford function of the first kind) was measured at a point 35 degrees from fixation and at the point of fixation. Three normal observers were used. The peripheral test point intercepted the retina between the optic nerve head and the ora serrata. At both test points, photopic and scotopic (one subject) Stiles-Crawford function peaks were contained within the pupillary bound and approximated the center of the pupil. Directionality at the two points was rather similar. These findings add strength to the argument that retinal receptors align approximately with the center of the exit pupil of the eye. Evidence for stability in Stiles-Crawford peak location in time is also presented. 相似文献