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31.
Anthony McCann 《Information & Communications Technology Law》2005,14(3):217-240
The paper starts by pointing to the lack of any theoretical analysis for the concepts of 'the commons' and 'information' in the general reference to the 'enclosure of the information commons'. The author suggests, instead, the concept of 'enclosure' as a key to understanding of 'the information commons', although it is underdeveloped and often equated with privatization or commodification. This paper attempts to establish a systematic theory of enclosure that enables examination of possible contradictions that may lie deep within the 'information commons'.
相似文献
The information commons is an idea whose time has come. In part this is a result of pressures that face the commons. Issues related to intellectual property law in particular are leading to what many are now calling the enclosure of the information commons—a process that separates people from ideas. This process is analogous to the fencing off of the English commons, an act that separated people from the material resources they needed for their survival. (Info-commons.org, 2002)
Within a repressive society, even progressive movements threaten to turn into their [declared] opposite to the degree to which they accept the rules of the game. (Herbert Marcuse, 1965)
Unless we demonstrate greater caution with analytical models that are products, as they all are, of particular histories, we are in danger not only of solving but also of producing tragedies and dilemmas in the commons and elsewhere. (Pauline E. Peters, 1987)
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A large body of data suggest that brain cholecystokinin (CCK) systems are involved in the regulation of anxiety, and numerous studies have demonstrated that CCK-4, a CCKB agonist, reliably induces panic attacks in patients with panic disorder. Recently, pentagastrin, a commercially available CCKB agonist, has been reported to have similar anxiogenic properties. To further explore the utility of pentagastrin as a challenge agent and to determine whether its effects are dose-related, a dose-response study was conducted in ten healthy volunteers. Pentagastrin (0.2 microgram/kg, 0.6 microgram/kg and 1.0 microgram/kg) and inactive placebo were infused over one minute on four separate challenge days in a double-blind fashion. Subjects received pentagastrin while participating in a structured social interaction task. Repeated measures of anxiety, blood pressure, pulse, ACTH, and cortisol were taken at baseline and postinfusion. Pentagastrin administration led to increases in anxiety, pulse, ACTH, cortisol and physical symptoms of panic, in a dose-related manner. Participation in the social interaction task led to increases in measures of anxiety as well as increases in pulse and blood pressure. Few differences were found between the 0.2 microgram/kg dose of pentagastrin and placebo, or between the 0.6 microgram/kg and the 1.0 microgram/kg doses of pentagastrin. These findings support the notion that CCK systems are involved in the regulation of anxiety, and suggest that the 0.6 microgram/kg dose may be optimal for increasing symptoms of anxiety while minimizing unpleasant side effects. The powerful anxiogenic effects of the social interaction task underscore the importance of contextual variables in challenge studies. 相似文献
34.
Danhauer Suzanne C.; McCann Judith J.; Gilley David W.; Beckett Laurel A.; Bienias Julia L.; Evans Denis A. 《Canadian Metallurgical Quarterly》2004,19(1):198
Random effects models were used to examine the association between behavioral disturbances in persons with Alzheimer's disease (N = 90) and caregiver depressive symptoms at 2-month intervals over an 18-month period. There was substantial variability in trajectories of change in caregiver depressive symptoms over time but no systematic increase in distress despite increased severity of dementia symptoms. Total behavioral disturbances were associated with higher levels of caregiver depressive symptoms: this effect was primarily attributable to aggressive behaviors. No consistent departure from linearity was evident in the relationship between behavior and depression over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Four self-driven photoelectrochemical hydrogen producers: n-TiO2/p-CdTe, n-TiO2/p-GaP, n-SrTiO3/p-CdTe and n-SrTiO3/p-GaP were constructed and examined in 1 M NaOH. the current-potential curves of the individual electrodes and the current-cell voltage relationships were measured. Cell current-density measurements versus time demonstrated that the output of each cell is stable for at least 12 h. the n-SrTiO3/p-GaP cell under xenon light irradiation was the most efficient at 0·7 per cent. the n-TiO2/p-GaP cell was estimated as the most efficient under solar light at 0·1 per cent. the stability of p-CdTe and its energy gap of 1·5 eV make it a prospect for use as a photocathode in future photoelectrochemical hydrogen producers. 相似文献
36.
CJ Anobile JA Talbot SJ McCann V Padmanabhan WR Robertson 《Canadian Metallurgical Quarterly》1998,4(7):631-639
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean +/- SD) throughout their menstrual cycles and in five post-menopausal women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7-4) revealed menstrual cycle stage- and postmenopausal-related differences in the serum gonadotrophin charge. There were differences in the proportion of FSH with an isoelectric point (pl) > 4.3 across phases of the menstrual cycle (P = 0.019): midcycle (MC) 50%; early to mid-follicular (EMF) 36%; late follicular (LF) 37%, luteal (L) 29% and following the menopause (PM) 17%. There was no significant difference in the proportion of LH with pl > 6.55 between midcycle (53%) and EMF, LF or L phases (36, 43 and 32% respectively); although all were greater than that found in the menopause (13%). Concanavalin A chromatography revealed less (P < 0.005) complex FSH and LH glycoforms at midcycle (63 and 13%) than in the EMF, LF and L phases (90 and 18; 90 and 20 and 93 and 24% respectively). Menopausal gonadotrophins were least complex (FSH 34%, LH 4%). There was a direct relationship between serum FSH and FSH pl/complexity, and less acidic FSH was associated with reduced FSH complexity. Increased oestradiol was associated with basic FSH isoforms during the menstrual cycle and reduced follicular phase FSH complexity. We conclude that changes in gonadotrophin glycoforms occur through the menstrual cycle which are related to changes in the prevailing steroid environment. Following the menopause oestrogenic loss resulted in acidic, relatively simple glycoforms. 相似文献
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According to action-control theory, volition plays a mediating role between the intention to learn (motivation) and goal-directed behavior (the use of learning strategies). Although extensive theoretical work has been done to document this flow of events, more empirical studies have been needed to identify the specific means by which volitional control protects the intention to learn and maintains the attempts to learn; our intention here was to address this gap in the literature. Using data from a sample of 487 college students in two different domains, we found that the positive effects of intrinsic goal orientation and self-efficacy on cognitive engagement were augmented by volitional control. We also found that the effects of volition differed by domain as well as by the type of learning strategy being considered. These results suggest that volitional control merits greater attention from those doing research in self-regulated learning. Copyright 1998 Academic Press. 相似文献
39.
Three studies investigated a range of parameters affecting individual differences in the incidence of hypnotically induced pseudomemory among hypnotizable Ss. Study 1 replicated Laurence and Perry's (1983) base rates for hypnotically induced pseudomemory response among hypnotizable subjects; in Study 2 the same response was analyzed under more strictly controlled stimulus conditions. Study 3 was an investigation of the impact of a broader range of stimulus events on response and a more sensitive test of the hypothesis that individual differences in pseudomemory effects are tied essentially to the social context of hypnosis. In all 3 studies, independent groups of Ss were tested who were highly responsive to hypnotic suggestion. Data indicated that the incidence of pseudomemory response was stable and consistent when stringent criteria of scoring were adopted. Also, for some Ss, real and suggested memories were maintained at one and the same time when hypnotically induced memory was examined in different test settings, suggesting that pseudomemories do not permanently overlay real experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Two experiments used the locus-of-cognitive-slack method to determine whether dual-task interference occurs before or after the response selection stage. The experiments used the overlapping tasks paradigm, in which 2 signals, each requiring a different speeded choice response, are presented in rapid succession. In Exp 1, stimulus–response (S–R) compatibility was manipulated by varying whether Task 2 stimuli were mapped onto their responses by a rule or arbitrarily. Compatibility effects were additive with the effects of degree of task overlap, manipulated by varying the stimulus onset asynchrony between the signals. Exp 2 examined 2 additional forms of S–R compatibility: symbolic compatibility (arrows vs letters) and spatial compatibility (the "Simon" effect). Effects of symbolic compatibility were additive with effects of degree of task overlap, whereas the effects of spatial compatibility and degree of task overlap were underadditive. It is argued that only a central-bottleneck model provides a consistent account of these results. The nature of the central bottleneck is considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献