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131.
Wood Joanne V.; Heimpel Sara A.; Newby-Clark Ian R.; Ross Michael 《Canadian Metallurgical Quarterly》2006,90(6):ii
Reports an error in "Snatching Defeat From the Jaws of Victory: Self-Esteem Differences in the Experience and Anticipation of Success" by Joanne V. Wood, Sara A. Heimpel, Ian R. Newby-Clark and Michael Ross (Journal of Personality and Social Psychology, 2005[Nov], Vol 89[5], 764-780). There are typographical errors in Table 2 (certain values should not have been in bold face). The corrected table is provided in the erratum. (The following abstract of the original article appeared in record 2005-15658-009.) Successes--defined broadly as meeting important standards or receiving positive evaluations--are widely assumed to be enjoyed equally by people with high self-esteem (HSEs) and low self-esteem (LSEs). Three studies examined the contradictory hypothesis that HSEs react more favorably to success than do LSEs and that success brings about certain unfavorable consequences for LSEs. Undergraduate participants reacted to a laboratory-manipulated success (Studies 1 and 2) or imagined highly positive events in the future (Study 3). Self-esteem differences emerged in anxiety, thoughts about the self, and (in Study 3) thoughts about non-self-related aspects of the event. LSEs were more anxious than HSEs after succeeding, success improved HSEs' self-relevant thoughts but not LSEs', and LSEs focused more on success's negative aspects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
The natural mouse pathogen polyoma virus is highly oncogenic in H-2k mice carrying the endogenous superantigen encoded by the mouse mammary tumor provirus Mtv-7. This superantigen results in deletion of Vbeta6 TCR-expressing polyoma-specific CD8+ CTL, which appear to be critical effectors against polyoma tumorigenesis. Here we have isolated cloned lines of CD8+ T cells from resistant (i.e., Mtv-7-) H-2k mice that specifically lyse syngeneic polyoma virus-infected cells and polyoma tumor cells. Nearly all these CTL clones express Vbeta6 and are restricted in their recognition of virus-infected cells by H-2Dk. Screening a panel of synthetic peptides predicted to bind to Dk, for which no consensus peptide binding motif is known, we identified a peptide corresponding to a nine-amino acid sequence in the carboxyl-terminus of the middle T (MT) protein (amino acids 389-397) that was recognized by all the Vbeta6+ CD8+ CTL clones. The inability of MT(389-397)-reactive CTL to recognize cells infected with a mutant polyoma virus encoding a MT truncated just proximal to this sequence indicates that MT(389-397) is a naturally processed peptide. The frequencies of precursor CTL specific for polyoma virus and MT(389-397) peptide were similar, indicating that MT(389-397) is the immunodominant epitope in H-2k mice. In addition, polyoma-infected resistant mice possess a 10- to 20-fold higher MT(389-397)-specific precursor CTL frequency than susceptible mice. This highly focused CTL response to polyoma virus provides a valuable animal model to investigate the in vivo activity of CTL against virus-induced neoplasia. 相似文献
133.
M Shams MD Kilby DA Somerset AJ Howie A Gupta PJ Wood M Afnan PM Stewart 《Canadian Metallurgical Quarterly》1998,13(4):799-804
The evolutionary theory of aging predicts that the equilibrium gene frequency for deleterious mutations should increase with age at onset of mutation action because of weaker (postponed) selection against later-acting mutations. According to this mutation accumulation hypothesis, one would expect the genetic variability for survival (additive genetic variance) to increase with age. The ratio of additive genetic variance to the observed phenotypic variance (the heritability of longevity) can be estimated most reliably as the doubled slope of the regression line for offspring life span on paternal age at death. Thus, if longevity is indeed determined by late-acting deleterious mutations, one would expect this slope to become steeper at higher paternal ages. To test this prediction of evolutionary theory of aging, we computerized and analyzed the most reliable and accurate genealogical data on longevity in European royal and noble families. Offspring longevity for each sex (8409 records for males and 3741 records for females) was considered as a dependent variable in the multiple regression model and as a function of three independent predictors: paternal age at death (for estimation of heritability of life span), paternal age at reproduction (control for parental age effects), and cohort life expectancy (control for cohort and secular trends and fluctuations). We found that the regression slope for offspring longevity as a function of paternal longevity increases with paternal longevity, as predicted by the evolutionary theory of aging and by the mutation accumulation hypothesis in particular. 相似文献
134.
135.
Use of an intravascular T1 contrast agent to improve MR cine myocardial-blood pool definition in man
The feasibility of improving myocardial/blood pool contrast in MR cine images through use of an intravascular contrast agent (Ferumoxtran, Advanced Magnetics, Inc., Cambridge, MA) was tested in four subjects. The contrast-to-noise ratio (CNR) demonstrated a trend toward improvement in the short axis and improved significantly in the long axis cine by an average of 128% (P < .05). Image intensity gradients at the myocardial/blood pool interface increased significantly in both the short and long axis (P < .01). It is expected that larger image intensity gradients at the endocardial border should improve the capabilities of automated segmentation algorithms, reducing the uncertainty and need for manual editing. 相似文献
136.
QY Liu AE Schaffner YH Chang K Vaszil JL Barker 《Canadian Metallurgical Quarterly》1997,33(6):848-864
Embryonic rat hippocampal neurons were cultured in a serum-free defined medium (MEM/N3) either directly on poly-D-lysine (PDL) or on a confluent monolayer of postnatal cortical astrocytes, C6 glioma cells, or Rat2 fibroblasts. Neurons on PDL were grown in MEM/N3 or in MEM/N3 conditioned for 24 h by astrocytes or C6 cells. Membrane capacitance (Cm) and gamma-aminobutyric acid (GABA)-, glycine-, kainate-, and N-methyl-D-aspartate (NMDA)-induced currents were quantified using whole-cell patch-clamp recordings. Cm as well as the amplitude and the density of these currents in neurons cultured on astrocytes were significantly greater than those in neurons grown on PDL after 24 and 48 h. C6 cells mimicked astrocytes in promoting Cm and GABA-, glycine-, and NMDA-evoked, but not kainate-evoked, currents. Cm and currents in neurons grown on Rat2 cells were comparable to those in neurons on PDL. Astrocytes maintained in culture for 3 months were noticeably less effective than freshly prepared ones just grown to confluence. Suppression of spontaneous cytoplasmic Ca2+ (Ca[c]2+) elevations in astrocytes by 1,2-bis(2-aminophenoxy) ehane-N, N, N, N-tetraacetic acid acetoxymethyl ester (BAPTA-AM) loaded intracellularly blocked the observed modulatory effects. Medium conditioned by either astrocytes or C6 cells mimicked the effects of direct coculture of neurons on these cells in promoting Cm and amino acid-evoked currents. Inclusion of antagonists at GABA and glutamate receptors in coculture experiments blocked the observed effects. Thus, diffusible substances synthesized and/ or secreted by astrocytes in a Ca(c)2+-dependent manner can regulate neuronal growth and aminoacid receptor function, and these effects may involve neuronal GABA and glutamate receptors. 相似文献
137.
The oxidation of several largely austenitic Fe-Cr-Ni alloys in 1 atm oxygen at 800–1200°C has been studied thermogravimetrically, metallographically, and in detail by electron probe micro analysis. Fe-Cr-Ni alloys of this type are protected by Cr2O3-healed scale, which thickens slower than on the corresponding binary Fe-Cr and Ni-Cr alloys, presumably because nickel and iron ions dope the Cr2O3 more effectively together than singly and/or because the alloy composition and ability to absorb cation vacancies are such as to produce a smaller vacancy activity gradient or level in the scale, or voids within it. The scale adhesion, as on Ni-Cr alloys, is generally good after long times, at least partly due to the convoluted alloy-oxide interface, in some cases to large intergranular Cr2O3-rich stringers, and possibly to the general specimen mechanical properties. Nonprotective stratified scale development is relatively unusual and often produces nickel-rich, alloy-particle-containing nodules, as on Fe-Ni alloys. Careful selection of ternary and more complex alloys with appropriate alloy interdiffusion coefficients and oxygen solubilities and diffusivities should permit development of materials with the best compromise between ease of Cr2O3 establishment, avoidance of breakaway, and readiness of scale healing. 相似文献
138.
Erbilgin N Gillette NE Mori SR Stein JD Owen DR Wood DL 《Journal of chemical ecology》2007,33(4):817-823
Host location and colonization by bark beetles is dependent upon the relative and absolute amounts of attractant and antiattractant
compounds available. Many investigations have lead to use of antiattractants for the management of these pests and have been
especially focused on verbenone. However, recent studies have identified new antiattractants for several species of bark beetles.
We report results of recent investigations of the response of western pine beetle, Dendroctonus brevicomis LeConte, to two recently identified antiattractants, acetophenone, and fenchyl alcohol, with verbenone as a standard of comparison,
in northern California. Release of both acetophenone and verbenone resulted in significantly lower trap catches of D. brevicomis in aggregation pheromone-baited traps, while fenchyl alcohol was inactive. Acetophenone was the only antiattractant that
did not reduce numbers of the most abundant predator of D. brevicomis, Temnochila chlorodia (Mannerheim), responding to the attractant pheromone of its prey. Aggregation pheromone-baited traps with acetophenone also
had the highest predator/prey ratio. Our results suggest that acetophenone may be part of the intra- and interspecific interactions
among sympatric species of bark beetles and may have application in their control. 相似文献
139.
140.
Factors controlling ammonia loss from trash covered sugarcane fields fertilized with urea 总被引:1,自引:0,他引:1
J. R. Freney O. T. Denmead A. W. Wood P. G. Saffigna L. S. Chapman G. J. Ham A. P. Hurney R. L. Stewart 《Nutrient Cycling in Agroecosystems》1992,31(3):341-349
Ammonia losses following surface applications of urea to trash covered sugar cane fields were investigated in four climatic zones of tropical Queensland. Volatilization of ammonia and evaporation of water were determined by micrometeorological techniques. The results showed that the pattern, rate and extent of ammonia loss were controlled by the availability of water in the trash and its evaporation. Water added by dewfall, rainfall or condensation of evaporated soil moisture dissolved some of the urea and allowed it to be hydrolyzed to ammonia by the urease enzyme in the sugarcane residues; when the water evaporated, ammonia was lost to the atmosphere.In the dry climatic zone, where no rain or dew fell, water addition to the trash by condensation of evaporated soil moisture was not sufficient to dissolve much urea so very little ammonia was lost. In the cool and warm moist zones, small additions of water to the trash from dew, light rain and condensation maintained a slow but steady pattern of ammonia loss over a period of six weeks and resulted in losses of 32% and 39% of the applied nitrogen. At the site in the wet zone, heavy rainfall apparently washed the urea from the trash layer into the soil and limited ammonia loss to 17% of the applied nitrogen.Substitution of ammonium sulfate for urea reduced ammonia loss to less than 1.8% of the applied nitrogen. 相似文献