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991.
992.
Work at the University of Ulster has been carried out to investigate methods of achieving startling print colour effects. It has been realised that by arranging fibre blends and distribution, pleasing aesthetic results are made possible. In this article Brian Hill and George Gray give a brief account of their research. 相似文献
993.
Comments on the article Fundamentalism: Sauce for the goose by K. Floyd (see record 2007-09680-001). Floyd reminds us that the application of a little logic to the propositions we claim are true can sometimes show us that our beliefs are untenable, and that such a finding "could turn out to be very freeing indeed". In particular, he uses one of the arguments some of us struggled with the first time we met logic as a discipline: If P is true then Q is true. Q isn't true. Therefore, P isn't true. Floyd applies this principle to religious belief: If I believe that P is true and Q is true when in fact P implies that 0 is false then I am truly inconsistent! He also shows how easily we are willing to use such logic on the beliefs of others but not on our own beliefs. The current authors' attempt to demonstrate that Floyd makes several questionable steps in his reasoning, thereby calling into question the conclusions he draws. Floyd has sought to point out the lack of thought behind numerous religious beliefs. The current authors accept this general observation, but they believe it unfair to attribute this difficulty only to religious beliefs. The difficulty with religious beliefs is not that they are not concerned with truth vs. non-truth, but rather that for a number of reasons, the difference between these two poles is often not obvious. The question of the validity of religious beliefs is a philosophically spiny one that has been addressed, sometimes adequately and sometimes in very illogical, emotional and violent fashions, for thousands of years. It seems obvious to the authors that "three minutes thought" is not sufficient to untangle such an issue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
Identification of olfactory cues used in host-plant finding by diamondback moth,Plutella xylostella (Lepidoptera: Plutellidae) 总被引:1,自引:0,他引:1
Kenneth A. Pivnick Blair J. Jarvis George P. Slater 《Journal of chemical ecology》1994,20(7):1407-1427
Olfactory attraction of female diamondback moths (Plutella xylostella) to odors of intact and homogenized host plants, as well as individual compounds characteristic of host plants, were investigated by behavioral and electrophysiological methods. Moths were attracted to odors ofBrassica juncea andB. napus seedlings in a Y-tube bioassay. Solvent fractions of homogenizedB. juncea leaves were attractive to moths whether or not isothiocyanates (IC) were present. Moths were attracted in Y-tube bioassays and to field traps baited with individual ICs. Volatiles fromB. juncea andB. napus elicited an electroantennogram (EAG) response and were attractive in the Y-tube bioassay. Allyl IC was shown to be the attractive component in homogenized plant volatiles but was found to be virtually absent from intact plant volatiles. Gas chromatographic fractionation of intact plant volatiles revealed a terpene-containing fraction to be most attractive to the moths. We were unable to isolate individual attractive compounds from this fraction. Our results suggest that certain elements of this fraction, possibly in combination, are important olfactory cues for host-plant finding by the diamondback moth with mustard oils playing an important and possibly synergistic role, particularly when plants are damaged. 相似文献
996.
DR Roberts DJ Vincent AM Speer DE Bohning J Cure J Young MS George 《Canadian Metallurgical Quarterly》1997,104(8-9):833-843
Multiple non-invasive methods of imaging brain function are now available for presurgical planning and neurobiological research. As these new methods become available, it is important to understand their relative advantages and liabilities, as well as how the information gained compares across different methods. A current and future trend in neurobiological studies as well as presurgical planning is to combine information from different imaging techniques. Multi-modal integration may perhaps give more powerful information than each modality alone, especially when one of the methods is transcranial magnetic stimulation (TMS), with its ability to non-invasively activate the brain. As an initial venture in cross comparing new imaging methods, we performed the following 2 studies, locating motor cortex with echoplanar BOLD fMRI and TMS. The two methods can be readily integrated, with concurring results, although each have important limitations. 相似文献
997.
The common assumption that emotional expression mediates the course of bereavement is tested. Competing hypotheses about the direction of mediation were formulated from the grief work and social-functional accounts of emotional expression. Facial expressions of emotion in conjugally bereaved adults were coded at 6 months post-loss as they described their relationship with the deceased; grief and perceived health were measured at 6, 14, and 25 months. Facial expressions of negative emotion, in particular anger, predicted increased grief at 14 months and poorer perceived health through 25 months. Facial expressions of positive emotion predicted decreased grief through 25 months and a positive but nonsignificant relation to perceived health. Predictive relations between negative and positive emotional expression persisted when initial levels of self-reported emotion, grief, and health were statistically controlled, demonstrating the mediating role of facial expressions of emotion in adjustment to conjugal loss. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Janet M. Hughes Erna J. Beal George W. Mushrush 《Petroleum Science and Technology》1995,13(4):413-409
A high paraffin, high nitrogen, low sulfur jet fuel derived from Athabasca tar sands was studied. The organo-nitrogen compounds in the fuel were isolated by mild acid extraction followed by silica-gel adsorption. Three extracts were derived from this fuel: a basic nitrogen compounds extract, BNC, in methylene chloride, a non-basic nitrogen compounds extract, NBNC, in methyl alcohol and an NBNC extract in methylene chloride. The major constituents of each extract were identified and quantitated by combined capillary column GC/MS. Alkyl substituted pyrroles, pyridines, indoles, tetrahydro-quinolines, carbazoles, and quinolines were the prevalent organo-nitrogen compounds present. Incompatibility tests were conducted on this fuel using the oxygen overpressure method with both doped and undoped fuel systems. The dopant of choice was cumene hydroperoxide. Practically no sediment formation was observed for the undoped fuel (0.1 mg/100mL fuel). The doped fuel matrix induced incompatibility behavior in proportion to the quantity of dopant present. 相似文献
999.
Graff Robert W.; Whitehead George I.; LeCompte Michael 《Canadian Metallurgical Quarterly》1986,33(3):276
Examined the effectiveness of cognitive-behavioral and supportive-insight group therapy with 46 women (aged 23–36 yrs) who had been divorced between 8 mo and 1? yrs. 12 clients were assigned to the cognitive-behavioral group; 12 were assigned to a supportive-insight group; and 22 Ss were assigned to 2 control groups. Differences between pre- and posttest, and pretest and follow-up scores on measures of depression (Beck Depression Inventory, Lubin Depression Checklist), self-esteem (Rosenberg Self-Esteem Inventory), and neuroticism (Eysenck Personality Inventory) were taken. When compared with the control groups on the posttest, both cognitive-behavioral and supportive-insight treatments were more effective on most criteria. At the 4-mo follow-up, cognitive-behavioral counseling continued to be beneficial, whereas the supportive-insight approach was consistently less effective. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Energy Deposition in a Model of Man: Frequency Effects 总被引:1,自引:0,他引:1
Stuchly Stanislaw S. Stuchly Maria A. Kraszewski Andrzej Hartsgrove George 《IEEE transactions on bio-medical engineering》1986,(7):702-711
A computer-controlled scanning system and implantable, nonperturbing electric field probes were used to measure spatial distributions of the electric field in a full scale homogeneous model of a human body. The measurements were performed at three frequencies (160, 350, and 915 MHz) in the far-field and in the near-field of resonant dipoles. The specific absorption rate (SAR) distributions and the averages for body parts and the whole body are analyzed as functions of frequency. In the far-field, the SAR decreases exponentially in the direction of wave propagation in the torso at all frequencies, and large gradients of the SAR are observed along the body main axis, particularly for the E polarization. At 160 and 350 MHz high local SAR's are produced in the neck. It appears that for plane wave exposures the ratio of the peak SAR to the whole-body average SAR does not exceed 20. In the near-field, large SAR gradients are also produced, and the ratios of the peak spatial SAR to the whole-body average SAR vary from about 30 to 250 depending on the frequency and polarization. It is suggested that for near-field exposures the whole-body average SAR is not a proper dosimetric measure, and the SAR averaged over any 0.1 of the tissue volume is recommended instead. 相似文献