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871.
Andrew Hall Norman Clark Rasheed Sulaiman M. V. K. Sivamohan B. Yoganand 《Knowledge, Technology, and Policy》2000,13(1):70-91
This article argues that the goals of agricultural research in poor countries have changed substantially over the last four
decades. In particular they have broadened from the early (and narrow) emphasis on food production to a much wider agenda
that includes poverty alleviation, environmental degradation, and social inclusion. Conversely, agricultural research systems
have proved remarkably resistant to the concomitant need for changes in research focus. As a result many, at both the national
and international level, are under great strain. In terms of public policy the article goes on to suggest that shortcomings
of existing conceptual approaches to technology development could be supplemented by adopting analytical principles that view
innovation in systemic terms. An approach where flows of knowledge between institutional nodes is a key to innovative performance
(the “National Systems of Innovation” approach) is suggested as one such conceptual framework that might help supplement conventional
policy analysis.
An earlier version of this paper was presented at a workshop “New Policy Agendas for Agricultural Research: Implications for
Institutional Arrangements” held on 28 March 2000 at the International Crops Research Institute for the Semi-Arid Tropics
(ICRISAT), Patancheru, India. The workshop was supported by the UK Department of International Development (DFID) Crop Post-Harvest
Programme as an output of the project “Optimising Institutional Arrangements.” 相似文献
872.
873.
ZEN MASTERS: A MAVERICK, A MASTER OF MASTERS, AND A WANDERING POET. By John Stevens, 161 pp. Kodansha International: Tokyo/NY/London, 1999. $13.00. THE DEVELOPING MIND: TOWARD A NEUROBIOLOGY OF INTERPERSONAL EXPERIENCE. By Daniel J. Siegel. 394 pp. New York: The Guilford Press, 1999. $37.95. JESUS: A PSYCHOLOGICAL BIOGRAPHY. By Donald Capps. 288 pp. St. Louis: Chalice Press, 2000. $29.99. 相似文献
874.
Randall R. Benson D. H. Whalen Matthew Richardson Brook Swainson Vincent P. Clark Song Lai Alvin M. Liberman 《Brain and language》2001,78(3):364-396
Candidate brain regions constituting a neural network for preattentive phonetic perception were identified with fMRI and multivariate multiple regression of imaging data. Stimuli contrasted along speech/nonspeech, acoustic, or phonetic complexity (three levels each) and natural/synthetic dimensions. Seven distributed brain regions' activity correlated with speech and speech complexity dimensions, including five left-sided foci [posterior superior temporal gyrus (STG), angular gyrus, ventral occipitotemporal cortex, inferior/posterior supramarginal gyrus, and middle frontal gyrus (MFG)] and two right-sided foci (posterior STG and anterior insula). Only the left MFG discriminated natural and synthetic speech. The data also supported a parallel rather than serial model of auditory speech and nonspeech perception. 相似文献
875.
A cognitive model of posttraumatic stress disorder 总被引:45,自引:0,他引:45
Posttraumatic stress disorder (PTSD) is a common reaction to traumatic events. Many people recover in the ensuing months, but in a significant subgroup the symptoms persist, often for years. A cognitive model of persistence of PTSD is proposed. It is suggested that PTSD becomes persistent when individuals process the trauma in a way that leads to a sense of serious, current threat. The sense of threat arises as a consequence of: (1) excessively negative appraisals of the trauma and/or its sequelae and (2) a disturbance of autobiographical memory characterised by poor elaboration and contextualization, strong associative memory and strong perceptual priming. Change in the negative appraisals and the trauma memory are prevented by a series of problematic behavioural and cognitive strategies. The model is consistent with the main clinical features of PTSD, helps explain several apparently puzzling phenomena and provides a framework for treatment by identifying three key targets for change. Recent studies have provided preliminary support for several aspects of the model. 相似文献
876.
Its controversial past notwithstanding, psychopathy has emerged as one of the most important clinical constructs in the criminal justice and mental health systems. One reason for the surge in theoretical and applied interest in the disorder is the development and widespread adoption of reliable and valid methods for its measurement. The Hare PCL-R provides researchers and clinicians with a common metric for the assessment of psychopathy, and has led to a surge in replicable and meaningful findings relevant to the issue of risk for recidivism and violence, among other things. Most of the research thus far has been based on North American samples of offenders and forensic psychiatric patients. We summarize this research and compare it with findings from several other countries, including England and Sweden. We conclude that the ability of the PCL-R to predict recidivism, violence, and treatment outcome has considerable cross-cultural generalizability, and that the PCL-R and its derivatives play a major role in the understanding and prediction of crime and violence. 相似文献
877.
Trace eyeblink conditioning (with a trace interval ≥500 msec) depends on the integrity of the hippocampus and requires that participants develop awareness of the stimulus contingencies (i.e., awareness that the conditioned stimulus [CS] predicts the unconditioned stimulus [US]). Previous investigations of the relationship between trace eyeblink conditioning and awareness of the stimulus contingencies have manipulated awareness or have assessed awareness at fixed intervals during and after the conditioning session. In this study, we tracked the development of knowledge about the stimulus contingencies trial by trial by asking participants to try to predict either the onset of the US or the onset of their eyeblinks during differential trace eyeblink conditioning. Asking participants to predict their eyeblinks inhibited both the acquisition of awareness and eyeblink conditioning. In contrast, asking participants to predict the onset of the US promoted awareness and facilitated conditioning. Acquisition of knowledge about the stimulus contingencies and acquisition of differential trace eyeblink conditioning developed approximately in parallel (i.e., concurrently). 相似文献
878.
L. Clark Johnson Randal Beaton Shirley Murphy Kenneth Pike 《International journal of stress management》2000,7(4):247-267
Data from a longitudinal occupational health survey of professional fire fighters were used to explore the potential impact of two types of methodological bias: sample selection and reactivity. No significant differences on demographic variables were observed between the group who first responded after a within-study change in survey administration format (Delayed) and respondents who had completed surveys since the study's inception (Initial). However, statistically significant differences in the study's 26 outcome measures provided some evidence that between-group differences did exist and that an administration format type of response bias was also potentially present. The effect sizes associated with the 37 observed significant differences ranged from small to medium. These results provide a context for a reexamination of standard techniques for the identification and interpretation of survey research biases. Methods are suggested to strengthen tests for selection bias and to minimize the impact of response biases. 相似文献
879.
This study assessed the effects of gender, race, and social class on the general and area-specific self-esteem of high school students. One hundred and ninety-five high school students served as subjects in a 2 (gender: male, female) X 2 (race: black, white) X 3 (social class: low, middle and high) factorial design. The Rosenberg General Self-Esteem, the Piers-Harris Children's Self-Concept, and the Brookover Self-Concept of Ability and School Achievement scales were the measures of either general or specific self-esteem. Females, whites, and lower social class adolescents were consistently lower in their self-esteem scores than were males, blacks, and upper social class teenagers, respectively. White females were found to be lower in general and happiness self-esteem than all other gender by race subgroups. High SES white students were lower on the happiness and behavior self-esteem measures than black students and white middle-class students. Black males and white females were less confident in their school ability than were black females and white males. 相似文献
880.
Cognitive—clinical theorists such as Beck have implicated various personality traits as vulnerability factors in the experience of negative, distressing cognitions. A cluster analysis, performed on the basis of Ss' responses to a questionnaire specially constructed to assess anxious and depressive thoughts for features such as frequency, sadness, worry, controllability and unacceptability, demonstrated individual differences in the experience of negative cognitions. These differences were associated with varying levels of trait anxiety, dysphoria and obsessionality. Further analysis revealed that trait anxiety and neuroticism were more strongly associated with depressive rather than anxious cognitions. Obsessional complaints evidenced minimal association with anxious thoughts, though a moderate correlation was obtained between the former and depressive self-statements. It is suggested that personality factors are influential in the experience of negative cognitions in a highly specific manner. 相似文献