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81.
Ab initio calculations have been performed to determine the energetics of oxygen atoms adsorbed onto graphene planes and the possible reaction path extracting carbon atoms in the form of carbon monoxide. From the energetics it is confirmed that this reaction path will not significantly contribute to the gasification of well ordered carbonaceous chars. Modelling results which explore this limit are presented. 相似文献
82.
JA Beatty JJ Callanan A Terry O Jarrett JC Neil 《Canadian Metallurgical Quarterly》1998,72(1):767-771
We describe the histopathological, immunohistochemical, and molecular characterization of a lymphoma arising in a 7-year-old cat following experimental infection with feline immunodeficiency virus (FIV). The tumor was high grade and of B-cell lineage. The transformed cell had an immature phenotype (CD79a+, CD79b-, CD21-, immunoglobulin heavy and light chain negative), confirmed by antigen receptor gene analysis, which showed germ line configuration. Single-copy, clonally integrated FIV provirus was detected in tumor genomic DNA. FIV p24 antigen was not detected in tumor cells by immunostaining. This study provides the first evidence that the feline lentivirus may play a direct role in cell transformation under certain circumstances. 相似文献
83.
L. E. L. Rasmussen Terry D. Lee G. Doyle Daves Jr. Michael J. Schmidt 《Journal of chemical ecology》1993,19(10):2115-2128
In their natural ecosystems, the sexes of Asian elephants,Elephas maximus, live separately. For several weeks prior to ovulation, the urine and cervical mucus of female Asian elephants contain extractable chemical agents of low volatility that elicit a high frequency of flehmen responses from bull elephants as an integral part of mating. Subsequent to flehmen responses, male sexual arousal occurs and, if the female is available, mating results. During the course of our project to determine the agent(s) and describe the responses associated with female to male sexual communication, we have identified an unusual compound. This compound, apparently the sole component of the active fraction, was identified by mass, proton nuclear magnetic resonance, ultraviolet/visible, and infrared spectrometries as indolo-[2,1-b] quinazoline-6,12-dione (tryptanthrine). Exhaustive and repetitive bioassays established that pure authentic (synthetic) tryptanthrine was not the compound responsible for the bioresponse. Rather a coeluting minor component, also of low volatility, elicited the male bioresponse. 相似文献
84.
Gold James M.; Berman Karen Faith; Randolph Christopher; Goldberg Terry E.; Weinberger Daniel R. 《Canadian Metallurgical Quarterly》1996,10(1):3
Deficits in working memory have been proposed to explain the performance failures of frontally lesioned primates on delayed alternation (DA) and delayed response (DR) tasks. The authors examined a computerized test of delayed response alternation (DRA), which combines elements of DR and DA in a sample of 18 normal volunteers who underwent oxygen-15 PET regional cerebral blood flow scans during the DRA and a sensorimotor control task. Significant activations were observed in a network of frontal, parietal, occipital, and temporal regions during initial task performance. A qualitatively similar but somewhat reduced set of activations was observed in a subset of participants who repeated the task after practice and instruction. These results are consistent with distributed models of working memory derived from studies of nonhuman primates and suggest that the frontal lobes contribute to human working memory function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Inconsistent item pair Variable Response Inconsistency (J-VRIN) and True Response Inconsistency (J-TRIN) scales were developed for the Jesness Inventory using 250 male and 250 female delinquents, ages 14–18, to detect the random and acquiescent sets. J-VRIN utility was assessed by comparing protocols of 262 male delinquents, ages 14–18, screened for probable randomness with matched-pair Minnesota Multiphasic Personality Inventory—Adolescent, with 500 all and part random computer-generated protocols. J-TRIN utility was assessed by comparing these protocols with 500 simulated acquiescent and nonacquiescent protocols. Specificities above .90 showed sensitivities up to .89 for J-VRIN and .85 and .62 for J-TRIN. Predictive power and overall effectiveness are reported for base rates of .20, .10, .067, and .05. Scales' relations to gender, race, age, and verbal fluency were investigated using an overlapping sample of 1,085 male and 356 female delinquents. Verbal fluency was the most salient. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
BR Chaitman SH Zhou B Tamesis A Rosen AB Terry KM Zumbehl K Stocke B Takase I Gussak PM Rautaharju 《Canadian Metallurgical Quarterly》1996,29(4):265-277
Serial electrocardiographic (ECG) changes are a critical component of the diagnostic algorithm for classification of myocardial ischemic events in large-scale clinical trials. This study describes a computerized serial ECG classification program developed at the St. Louis University Core ECG Laboratory for use in the Bypass Angioplasty Revascularization Investigation (BARI) trial, in which patients with multivessel coronary artery disease were randomized to receive either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. The St. Louis University program detects and codes serial changes in Q, ST, and T wave items according to Minnesota code (MC) criteria using a modified NOVACODE hierarchical classification system. Measurements using a seven-power calibrated coding loupe are used to generate the MC from a customized software program. Significant minor or major changes are detected by the serial comparison program and referred to a physician coder for verification. Serial comparison coding rules are used to adjust for weaknesses in the standard MC classification system resulting from instability at decision boundaries. Of 4,244 BARI randomized and registry study participants with follow-up ECGs received at the Core ECG Laboratory as of March 1995, a grade 2 MC Q wave progression was noted in 568 participants (13.4%) using MC criteria alone, as compared with 367 (8.6%) after the St. Louis University coding rules were applied. The incidence of grade 1 MC Q wave progressions was 16.4% (697/4,244) versus 6.1% (259/4,244) when the St. Louis University program was applied. Intraobserver variability for grade 2 Q wave progression codes determined from a sample of 812 serial. 相似文献
87.
Grant Willson Robert Miller Dennis McKean Nicholas Clecak Terry Tompkins Donald Hofer Josef Michl John Downing 《Polymer Engineering and Science》1983,23(18):1004-1011
The design, synthesis, formulation, and process optimization of a new mid-UV resist are described. The synthesis of a spectrally matched sensitizer was guided by semiempirical quantum mechanical calculations that predict the effect of structural changes on optical absorption characteristics. The formulation was guided by computer profile simulation studies and the process development by a response surface analytical procedure. These techniques allowed formulation optimization to be achieved on the basis of an understanding of the complex interactions between the resist dissolution response functions and the modulation transfer function of the exposure tool for which the resist was designed. 相似文献
88.
Addition polyirnide oligomers with nadimide end groups (I) have been synthesized from 4,4′-oxydiphthalic anhydride and 3,3′,4,4′-benzophenone tetracarboxylic acid dianhydride with several isomeric diamines and, nadic anhydride. The low molecular weight amic acid? and corresponding imides were isolated and characterized. Solubility and melt-flow properties of the imide prepolymers were studied to determine the applicability of the resins as adhesives and composite matrices. Thermomechanical transitions of the polymers were obtained by torsional braid analysis. Properties were compared with a similar addition polymer, P13N. 相似文献
89.
Gold Richard M.; Kapatos Gregory; Prowse James; Quackenbush Patricia M.; Oxford Terry W. 《Canadian Metallurgical Quarterly》1973,85(1):52
Performed 3 experiments on small groups (n = 2-6) of thirsty Carworth female albino rats. Cool water suppressed water intake. The suppression was apparent from the 1st min of drinking. Suppression occurred for both short (20-min) and long (100-min) daily drinking sessions, and occurred whether the water was available from a sipper tube or a bowl. When cellular hydration was delayed by giving Ss isotonic saline instead of water, the suppression by cooling was enhanced. Cool-water suppression of water intake appears to be a short-latency satiety mechanism that anticipates cellular and extracellular hydration. (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Four groups of 12 participants were hired to code videotaped group interactions using the Bales coding system (R. F. Bales, 1950). Each of the 4 groups experienced different leader behaviors of either high or low consideration in conjunction with either high or low initiating structure. Results indicate that subordinates did not perceive the leader manipulations as different but that these manipulations caused differences in quantity and quality of work. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献