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191.
The dissolution of a single stationary bubble held in place by a horizontal plate is commonly observed experimentally. For several decades the standard approach to the analysis of such dissolution data has been to apply a correction factor of ln(2)=0.69 to the Epstein-Plesset equation for an isolated bubble. In this paper, the transport equations for a stationary bubble touching a plate are solved numerically for the common case where the flow field caused by the change in system volume as the bubble dissolves can be neglected. It is found that the total bubble lifetime is not well characterised by the use of the ln(2) factor. However, in most experimental situations, the initial stages of bubble dissolution are not captured. For low gas solubilities the use of a correction factor of 0.69 to the Epstein-Plesset equation is appropriate once the initial transients have dissipated. The correction factor varies from 0.69 to 0.77 across the full range of situations described in this paper. The mathematical model is validated by comparison to experimental data. 相似文献
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S Sonza RE Kiernan AL Maerz NJ Deacon DA McPhee SM Crowe 《Canadian Metallurgical Quarterly》1994,56(3):289-293
Cytocidal retrovirus infection is characterized by rapid accumulation of unintegrated viral DNA forms. These are thought to be generated by multiple rounds of reinfection and have been suggested to play a central role in cytopathogenesis. Here we have reviewed the work done in this area with HIV-1, mostly using acutely and chronically infected T cell and monocytic cell lines and in some cases T cells blocked at S phase of the cell cycle by aphidicolin treatment. To these studies, we have compared our findings with HIV-1 infected primary peripheral blood monocyte-derived macrophages and untreated and growth-arrested MT-2 cells, two biologically disparate cell populations. Using 1- and 2-long terminal repeat (LTR) circular forms as indicators of unintegrated viral DNA, we found similar rapid accumulation in both untreated and growth-arrested MT-2 cells. In contrast, we found much lower levels in monocyte/macrophages. Our findings suggest that accumulation of unintegrated viral DNA does not require virus production and reinfection in growth-arrested T cells. The significantly lower levels found in monocyte/macrophages may reflect superinfection resistance, allowing the maintenance of a persistent infection. 相似文献
195.
Schlesier-Carter Barbara; Hamilton Sharon A.; O'Neil Patrick M.; Lydiard R. Bruce; Malcolm Robert 《Canadian Metallurgical Quarterly》1989,98(3):322
29 bulimics and 16 controls from the general population were first assessed on levels of depression using the Schedule for Affective Disorders and Schizophrenia—Change Version and the Beck Depression Inventory (BDI). Bulimics were significantly more depressed than controls. Bulimics differed significantly from controls on all cognitive measures associated with depression (Automatic Thoughts Questionnaire, Dysfunctional Attitude Scale, and Attributional Style Questionnaire), but differences on these measures were nonsignificant when depression, as measured by the BDI, was controlled. Bulimics differed from controls regardless of level of depression on the 3 scales of the Restraint Inventory, the Rationalization and All-or-None scales of the Thoughts About Eating Inventory, and most of the 8 scales of the Eating Disorders Inventory. Bulimics showed more maladaptive thinking associated with depression, but these differences likely reflect the levels of depression for each group. The differences on the measures of cognitive and behavioral symptoms of bulimia remained when the level of depression was controlled statistically. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Consumers' perceptions regarding the acceptability of treatments for mental disorders can have a direct effect on the clinical practices of professional psychologists. This exploratory study compared the acceptability of single and combined treatments commonly offered to adults with depression (cognitive-behavioral therapy or interpersonal therapy—each by itself and in combination with medication—and support group with medication). All treatments were seen as acceptable, but psychotherapy alone was more desirable than when combined with medication. Support group with medication was least acceptable. Implications for professional practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
198.
Charles Fairhurst Ferruccio Gera Paul Gnirk Malcolm Gray Bengt Stillborg 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1993,8(3)
The International Stripa Project was a cooperative research and development project among several member countries of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development. The scientific and technical objectives of the project were to investigate several aspects of technology concerned with the feasibility and safety of disposal of long-lived, heat-generating radioactive waste at depth in granitic rocks. In particular, the Stripa Project addressed: 1) the development of instruments and procedures to characterize candidate repository sites; 2) the understanding and modelling of groundwater flow and solute transport in fractured crystalline rock; and 3) the design of engineered barriers capable of contributing to waste isolation by restricting groundwater flow in proximity to the waste containers and in the surrounding host rock. This overview summarizes the work focussed on natural barriers and engineered barriers. 相似文献
199.
Previous studies of covert orienting in Alzheimer's disease (AD) have investigated exogenous and endogenous processes separately. We aimed to investigate how the 2 modes of orienting interact to control attention in healthy older participants and patients with AD. The covert orienting of visual attention task (COVAT) with abrupt onset cues was used in all experiments. In Experiments 1 and 2, predictive information was added to cues to initiate an endogenous orienting response. Results showed that healthy older participants were able to use endogenous processes to inhibit exogenous orienting. In contrast, patients with AD were unable to inhibit exogenous orienting to cues even when targets rarely appeared there. Experiment 3 investigated inhibition of return (IOR) in patients with AD. Both healthy older controls and patients with AD showed a normal IOR, suggesting that exogenous orienting processes are relatively unaffected by the normal aging process or in patients with AD. A model of covert orienting in which exogenous and endogenous orienting processes interact to control attentional behaviors is discussed. 相似文献
200.
Suggests that K. C. Mace and H. D. Warner's (1973) ratings data of psychology journals say more about the orientation of departmental chairmen than they do about the journals' professional reputations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献