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991.
L. J. Van Poolen R. T. Jacobsen M. Jahangiri 《International Journal of Thermophysics》1986,7(3):513-524
A comparison of the prediction of the critical density for ethylene and oxygen from available coexistence density values using three methods is presented. The conventional rectilinear diameter, the rectilinear diameter with an additional term to represent the postulated curvature near the critical point, and the critical liquid volume fraction were each utilized to predict critical density values for ethylene and oxygen. The correlating functions and fitted constants for the three techniques are given for different ranges of saturation density values. The accepted saturation lines for ethylene and oxygen calculated from new correlations of thermodynamic properties for these fluids were used in this study. The critical density of ethylene was predicted using coexistence density values from 220 to 230 K and from 220 to 282.34 K. Similarly, the critical density for oxygen was predicted using coexistence densities from 100 to 116 K, from 100 to 154.004 K, and from 100 to 154.571 K. Values of the critical density predicted using the three methods are compared with the accepted critical density values for these fluids. The ability of the three methods to predict accurate critical density values using saturation densities at temperatures removed from the critical point is assessed.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A. 相似文献
992.
In addition to its interaction at hypothalamic sites to affect feeding and energy expenditure, leptin has been shown to exhibit a proliferative response in erythropoietic cells. The functional leptin receptor is also present in pancreatic islets and we now demonstrate that a commonly used clonal insulin secreting beta-cell line, RINm5F, expresses high levels of the Ob-Rb mRNA. Leptin causes an increase in tyrosine phosphorylation of a number of intracellular proteins and a dose related (10 nM-200 nM) increase in expression of the immediate-early gene, c-fos. This precedes a leptin induced proliferative response in serum-deprived RINm5F cells, which suggests that leptin might be involved in the complex regulation of proliferation of the pancreatic beta-cell. 相似文献
993.
Polychlorinated biphenyl equilibria in an estuarine system 总被引:1,自引:0,他引:1
The stability of the partition of polychlorinated biphenyl (PCB) congeners between water and the compartments of particulate matter (seston), surface sediment, net-plankton and mussels has been investigated for 1.5 years. Samples were regularly obtained from four stations, representing River Rhine, brackish and saline estuarine and stagnant saline conditions. In spite of the PCB gradients, from freshwater to seawater, and time variations in concentrations, the partition coefficients Kd (distribution coefficients) were very stable for each of the congeners. This demonstrates that the partition between water and the other compartments is due to processes which reach their equilibrium within weeks, independent of the local variations in concentrations. This confirms the non-foodchain accumulation concept of Schneider [1] for aquatic organisms. 相似文献
994.
Roth Philip L.; Van Iddekinge Chad H.; Huffcutt Allen I.; Eidson Carl E. Jr.; Bobko Philip 《Canadian Metallurgical Quarterly》2002,87(2):369
Previous studies of standardized ethnic group differences in the employment interview have shown differences to be relatively small. Unfortunately, many researchers conducting interview studies have not considered the issue of range restriction in research design. This omission is likely to lead to underestimates of standardized ethnic group differences (d) when the interview is considered as an initial screening device or used in combination with other initial screening devices. The authors found that 2 forms of a behavioral interview were associated with standardized ethnic group differences of .36 and .56 when corrected for range restriction. These differences are substantially larger than previously thought and demonstrate the importance of considering a variety of study design characteristics in obtaining the appropriate parameter estimates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
J. Nijs S. Sivoththaman J. Szlufcik K. De Clercq F. Duerinckx E. Van Kerschaever R. Einhaus J. Poortmans Tom Vermeulen R. Mertens 《Solar Energy Materials & Solar Cells》1997,48(1-4)
Fabrication technologies for multicrystalline silicon (mc-Si) solar cells have advanced in recent years with efficiencies of mc-Si cells exceeding 18%. Intense efforts have been made at laboratory level to improve process technology, growth methods, and material improvement techniques to deliver better devices at lower cost. Deeper understanding of the physics and optics of the device led to improved device design. This provided a fruitful feedback to the industrial sector. Both screenprinting and buried-contact technologies yield cells of high performance. An increasingly large amount of research activity is also focussed on the fabrication of thin solar cells on cheap substrates such as glass, ceramic, or low quality silicon. Success of these efforts is expected to lead to high efficiency devices at much lower costs. Efforts are also being put on low thermal budget processing of solar cells based on rapid thermal annealing. 相似文献
996.
Rapport Lisa J.; Friedman Sara L.; Tzelepis Angela; Van Voorhis Amy 《Canadian Metallurgical Quarterly》2002,16(1):102
[Correction Notice: An erratum for this article was reported in Vol 16(3) of Neuropsychology (see record 2007-17085-001). On Page 102, in the byline and in the author note, and on page 109 in the Rapport et al. (2001) reference, Sara Friedman's middle initial incorrectly reads "L." Her correct middle initial is "R."] Emotional competence and deficits that may disrupt interpersonal interactions were evaluated in 28 adults with attention-deficit hyperactivity disorder (ADHD) and 28 demographically equivalent controls. Participants completed tasks assessing affect recognition and experienced emotional intensity. Adults with ADHD performed worse in affect recognition than did adults without the disorder; however, the impairment was unrelated to gross perceptual processes, fundamental abilities in facial recognition, or attentional aspects of affect perception. Moreover, intensity of experienced emotion moderated affect recognition: Among controls, experienced emotion facilitated affect recognition. Among adults with ADHD, who reported significantly greater intensity, experienced emotion was inversely related to affect recognition. Results are consistent with theories of ADHD as a deficit in behavioral inhibition; yet, results may merely reflect a constellation of deficits associated with the disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
OBJECTIVES: This study sought to identify risk markers associated with the provision of new restorations in children and to investigate whether the carious status of a tooth surface is associated with the restorative decisions of dentists. METHODS: A total of 911 schoolchildren in grades one, two, and three were randomly selected from the island of Montreal, Quebec, Canada. Dental examinations were carried out in 1990, 1991, and 1992. Tooth surfaces of first permanent molars were classified as sound, noncavitated, and cavitated. The carious status of a tooth was matched with restorative decisions reported to the insurance board. RESULTS: The presence of a carious cavity was a strong risk marker for placement of new restorations (odds rations > or = 4.11). After one year, less than 2 percent of sound tooth surfaces of first permanent molars were restored and about 21 percent of noncavitated tooth surfaces were restored. When new class I restorations placed in maxillary first permanent molars within 3-6 months after the baseline examination were evaluated, we found that between 73 percent and 86 percent of these new restorations were placed in sound or noncavitated tooth surfaces. A similar trend also was observed in mandibular first permanent molars. Poor agreement between epidemiologic diagnosis and restorative decisions was found. The restorative profile of dentists was a significant risk marker for placement of new restorations. CONCLUSION: The majority of new restorations in first permanent molars were placed in sound and noncavitated tooth surfaces because of the ubiquitous prevalence of these tooth surfaces and the validity problems of current caries diagnosis methods. 相似文献
998.
Realistic speech animation based on observed 3D face dynamics 总被引:1,自引:0,他引:1
Muller P. Kalberer G.A. Proesmans M. Van Gool L. 《Vision, Image and Signal Processing, IEE Proceedings -》2005,152(4):491-500
An efficient system for realistic speech animation is proposed. The system supports all steps of the animation pipeline, from the capture or design of 3D head models up to the synthesis and editing of the performance. This pipeline is fully 3D, which yields high flexibility in the use of the animated character. Real detailed 3D face dynamics, observed at video frame rate for thousands of points on the face of speaking actors, underpin the realism of the facial deformations. These are given a compact and intuitive representation via independent component analysis (ICA). Performances amount to trajectories through this 'viseme space'. When asked to animate a face, the system replicates the 'visemes' that it has learned, and adds the necessary coarticulation effects. Realism has been improved through comparisons with motion captured groundtruth. Faces for which no 3D dynamics have been observed can be animated nonetheless. Their visemes are adapted automatically to their physiognomy by localising the face in a 'face space'. 相似文献
999.
Heritability estimates, by year of freshening of daughter, were obtained from daughter-dam and granddaughter-granddam regressions using 61,482 triply matched first lactations of artificially sired Holstein cows obtained from the Northeast Dairy Records Processing Laboratory. After adjusting for herd-year-season effects, residual effects may include additive and other genetic effects of the animal, maternal effects, cytoplasmic effects, and other environmental effects. Analysis of residuals showed that cytoplasmic effects accounted for no variation in milk and fat yield and fat percent. Weighted yearly heritability estimates and standard errors from daughter on dam regressions were .35 +/- .01 for milk yield, .30 +/- .01 for milk fat yield, and .63 +/- .01 for milk fat percent and from daughter on granddam regressions were .34 +/- .03 for milk production, .28 +/- .03 for milk fat production, and .55 +/- .03 for milk fat percent. The differences between daughter-dam and daughter-granddam heritability estimates, which estimate twice the fraction of variance due to cytoplasmic effects, were negative and not statistically significant for milk fat yield and also were negative but highly significant for milk fat percent. 相似文献
1000.