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991.
Science smiles     
  相似文献   
992.
Science Smiles     
  相似文献   
993.
The political uncertainties surrounding Hong Kong's future as a British Crown Colony have not inhibited either the Hong Kong Government or its particular version of a University Grants Committee (UGC) system from devising and planning a continuing expansion of higher education at a time when most other countries are levelling off or contracting their own.This article deals with the many unique features of the Hong Kong situation of which perhaps the most important is the nature of the Hong Kong Government - traditionally colonial and potentially authoritarian, not elected yet highly sensitive to Chinese opinion both internally and externally, and highly efficient in most of its management activities in spite of a strongly laisser faire tradition.The Hong Kong UGC system is charged with much wider planning functions throughout higher education than elsewhere and is responsible for the polytechnic as well as the two universities - hence its trans-binary designation as the University and Polytechnic Grants Committee. While this has helped its overall planning and academic guidance roles, it has involved it in severe difficulties in relation to its basic financial role which requires it to develop methodologies of financial assessment of Polytechnic costs for which no overseas models exist. Its academic membership is still entirely from overseas, with inevitable repercussions on its ability to arrange adequate collective discussion and its reliance on its local secretariat who act as the Government's de facto Department of Higher Education.  相似文献   
994.
Expert systems encode human expertise in limited domains by representing it usingif-then rules. This article explains the development and applications of expert systems.  相似文献   
995.
In 671 mother–child (49% male) pairs from an epidemiological birth cohort, we investigated (a) prospective associations between DNA methylation (at birth) and trajectories (ages 7–13) of oppositional defiant disorder (ODD), and the ODD subdimensions of irritable and headstrong; (b) common biological pathways, indexed by DNA methylation, between ODD trajectories and attention deficit hyperactivity disorder (ADHD); (c) genetic influence on DNA methylation; and (d) prenatal risk exposure associations. Methylome‐wide significant associations were identified for the ODD and headstrong, but not for irritable. Overlap analysis indicated biological correlates between ODD, headstrong, and ADHD. DNA methylation in ODD and headstrong was (to a degree) genetically influenced. DNA methylation associated with prenatal risk exposures of maternal anxiety (headstrong) and cigarette smoking (ODD and headstrong).  相似文献   
996.
997.
998.
Acknowledgements     
  相似文献   
999.
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response.  相似文献   
1000.
Lick suppression experiments with rats revealed that the magnitude of both second-order conditioning (Experiment 1) and sensory preconditioning (Experiment 2) was superior when that conditioning was based on backward (US→CS) relative to forward (CS→US) first-order pairings of a CS and US. The superiority of backward relative to forward first-order conditioning on suppression to the higher order cues can be understood by assuming that the magnitude of higher order conditioning was determined by a memory representation of the higher order cues that provided information about the expected temporal location of the US. The results suggest that temporal information such as order between paired CSs and USs was encoded, preserved, and integrated with memory for the higher order stimuli. The relevance of these findings to memory integration in Pavlovian learning, the temporal coding hypothesis (Barnet, Arnold, & Miller, 1991; Matzel, Held, & Miller, 1988), backward excitatory conditioning, and the associative structure that underlies second-order Pavlovian fear conditioning are discussed.  相似文献   
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