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81.
Alexander Charles N.; Langer Ellen J.; Newman Ronnie I.; Chandler Howard M.; Davies John L. 《Canadian Metallurgical Quarterly》1989,57(6):950
Can direct change in state of consciousness through specific mental techniques extend human life and reverse age-related declines? To address this question, 73 residents of 8 homes for the elderly (mean age?=?81 years) were randomly assigned among no treatment and 3 treatments highly similar in external structure and expectations: the Transcendental Meditation (TM) program, mindfulness training (MF) in active distinction making, or a relaxation (low mindfulness) program. A planned comparison indicated that the "restful alert" TM group improved most, followed by MF, in contrast to relaxation and no-treatment groups, on paired associate learning; 2 measures of cognitive flexibility; word fluency; mental health; systolic blood pressure; and ratings of behavioral flexibility, aging, and treatment efficacy. The MF group improved most, followed by TM, on perceived control. After 3 years, survival rate was 100% for TM and 87.5% for MF in contrast to lower rates for other groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Stark Kevin D.; Humphrey Laura L.; Laurent Jeff; Livingston Ronnie; Christopher John 《Canadian Metallurgical Quarterly》1993,61(5):878
Contribution of cognitive, behavioral, and family environment variables to the differentiation of depressive and anxiety disorders in children was explored. 59 children from Grades 4–7 (14 diagnosed with a depressive disorder, 16 diagnosed with depressive and anxiety disorders, 11 diagnosed with an anxiety disorder, and 18 nondisturbed controls) completed measures of the depressive cognitive triad, depressive cognitions, social skills, family environment, and maladaptive family messages. Results of a stepwise discriminant function analysis indicated that 2 discriminant functions composed of 7 variables from the cognitive, behavioral, and family environment domains accounted for 91% of the between-groups variance. Results suggest that depressive disorders can be distinguished from anxiety disorders on the basis of ratings of cognition, social skills, and family environment. Implications for existing research and a model of depression during childhood are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Solar radiation is characterized by short fluctuations introduced by passing clouds. An analysis of these fluctuations with regard to solar energy applications should focus on the instantaneous clearness index. Its probability distribution for a given mean clearness index is, as a first approximation, independent from the season and partly also from the site. This is verified for four annual datasets from three different sites.An analysis of fluctuations in solar radiation must focus on their amplitude, persistence, and frequency of occurrence rather than their location in time. The Fourier analysis cannot satisfactorily provide this information since time series of the instantaneous clearness index exhibit no periodicity. Instead, a localized spectral analysis based on wavelet bases rather than on periodic-ones has been applied. This analysis allows the decomposition of the fluctuating clearness index signal into a set of orthonormal subsignals. Each of them represents one specific scale of persistence of the fluctuation.The annual mean square values of all subsignals have been analysed, permitting the allocation of the signal’s power content to the different scales of persistence of a fluctuation. These annual mean values agree well for the different datasets, indicating the existence of statistically significant mean square values of the fluctuations as a function of their persistence.The analysis offers a valuable tool for the estimation of power flow fluctuations introduced by direct solar energy systems. With further elaboration it may be applied by power system operators for network planning in distribution grids with a high density of embedded generation. 相似文献
84.
Franklin Kathryn M.; Janoff-Bulman Ronnie; Roberts John E. 《Canadian Metallurgical Quarterly》1990,59(4):743
Two studies were conducted to examine the long-term impact of parental divorce on beliefs about the self and others. In Study 1, college-aged children of divorce and students from intact families did not differ on 8 basic assumptions or on measures of depression. Those whose parents had divorced, however, were less optimistic about the success of their own future marriages. Assumptions about the benevolence of people best predicted the marital optimism of the parental divorce group, but not of the intact family group. In Study 2, assumptions about the benevolence of people were explored in terms of trust beliefs. College-aged children of divorce and a matched sample from intact homes differed only on marriage-related beliefs, not on generalized trust. Children of divorce reported less trust of a future spouse and were less optimistic about marriage. Exploratory analyses found that continuous conflict in family of origin adversely affected all levels of trust. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Ronnie Trnqvist Colin Servais Jean‐Christophe Ebinger Jan‐Anders E. Mnson 《Polymer Composites》2001,22(1):1-10
The non‐isothermal flow during compression molding of thermoplastic‐based composites having a planar, randomly oriented fiber structure has been investigated. Local interactions at the bundle‐bundle level were measured and a constitutive equation was derived to describe the shear and squeeze flow of the composites. This equation contains only micro‐mechanics‐related variables, and accounts for the temperature dependence of the interaction forces. The flow of the material under industrial processing conditions can thus be related to the deformation mechanisms of the reinforcement structure at the scale of the individual fibers Good agreement was obtained between the predicted and experimentally observed theological behavior of the composites in both shear and squeeze flow. The use of this approach to analyze the industrial molding of complex‐shaped parts is dis cussed. 相似文献
86.
Laser diodes (LD) are usually bonded onto heat sinks for the purposes of heat dissipation, mechanical support and electrical interconnect. In this study, energy dispersive X-ray analysis (EDX) and electron backscatter diffraction (EBSD) are employed to investigate the microstructure evolution of 80Au/20Sn solder joint in LD package. During reflow, Pt-Sn and (Au, Ni)Sn IMCs were formed at the respective LD/solder and solder/heatsink interfaces, while δ, β and ζ′ phases of Au/Sn intermetallics were found in the solder joint. The Au-rich β and ζ′ phases in the solder joint limit the growth of interfacial IMCs. Chip shear testing showed that the failure occurred within the LD, with partial brittle fracture at the GaAs substrate and partial interfacial delamination at the GaAs/SiN interface. The strong solder bond can be attributed to the high mechanical strength of 80Au/20Sn solder, which provides improved stability for high temperature applications. 相似文献
87.
Silicon-doped GaN layers grown by low-pressure metalorganic vapor-phase epitaxy with Si concentrations ranging from 2 × 1017 Si/cm3 to 9.2 × 1018 Si/cm3 were investigated by means of the perturbed angular correlation (PAC) technique applied to implanted 111In(Cd). An undoped GaN film is used as a reference. The Si atoms replace Ga atoms in the lattice, and silicon, being a group IV element, acts as a donor on the Ga site and contributes one extra electron to the conduction band. Hall-effect measurements confirmed that the free charge carrier density is essentially increased and of the order of the silicon concentration. PAC investigations of the annealing behavior after implantation of the 111In probes show that best recovery is achieved after annealing at 1200 K and that high silicon concentrations make GaN films more stable at high temperatures. Further, it was found that the temperature dependence of the electric field gradient is reduced by increasing Si concentrations. 相似文献
88.
Rosenbaum (1995) argued that the 1992 and 1993 volumes of Psychoanalytic Psychology detracted from the image of psychologists as being within science because they included articles about homophobia in psychoanalytic theory and practice. Labeling those who view homosexuality as a pathology "homophobic" is political, according to Rosenbaum, because such labeling is objective and neutral. I deconstruct Rosenbaum's use of the notions of objectivism and neutrality, and conclude that they function as masks for politics, ideology, and values. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Fantke P Juraske R Antón A Friedrich R Jolliet O 《Environmental science & technology》2011,45(20):8842-8849
A new dynamic plant uptake model is presented to characterize health impacts of pesticides applied to food crops, based on a flexible set of interconnected compartments. We assess six crops covering a large fraction of the worldwide consumption. Model estimates correspond well with observed pesticide residues for 12 substance-crop combinations, showing residual errors between a factor 1.5 and 19. Human intake fractions, effect and characterization factors are provided for use in life cycle impact assessment for 726 substance-crop combinations and different application times. Intake fractions typically range from 10?2 to 10?? kg(intake) kg(applied)?1. Human health impacts vary up to 9 orders of magnitude between crops and 10 orders of magnitude between pesticides, stressing the importance of considering interactions between specific crop-environments and pesticides. Time between application and harvest, degradation half-life in plants and residence time in soil are driving the evolution of pesticide masses.We demonstrate that toxicity potentials can be reduced up to 99% by defining adequate pesticide substitutions. Overall, leafy vegetables only contribute to 2% of the vegetal consumption, but due to later application times and higher intake fractions may nevertheless lead to impacts comparable or even higher than via the larger amount of ingested cereals. 相似文献
90.