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1.
The authors examined (a) how traumatic events are associated with children's dream structure and content and (b) which dream characteristics might moderate the negative impact of traumatic events on mental health. Participants were 122 Kurdish children (9-17 years old, M = 13.02, SD = 1.66). Their dreams were collected during 1 week using a semistructured dream diary and scored according to the dream atmosphere, the role of the dreamer, bizarreness, narrative quality, fragmentation and resolution, and content such as themes of death, persecution and rejection, hostility, and anxiety. The results substantiated the hypothesis that children exposed to a high level of traumatic events would report dreams characterized by unpleasant atmosphere, fragmented flow, and low levels of bizarre narrative quality. Pleasant dreams containing complete narratives and happy endings moderated the negative impact of traumatic events on children's mental health. The authors argue that dreaming allows cognitive-emotional processing of traumatic events and may thus enhance child well-being in war conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
This study examined the extent to which the intrinsic predispositions that modulate dream content serve as indicators of the hysterical tendency to conversion and dissociation. The Dream Themes Inventory, Dream Intensity Scale, Limbic System Checklist-33, Dissociative Experiences Scale, Eysenck Personality Questionnaire Revised-Short Form, Boundary Questionnaire-18, and scales for evaluating defense mechanisms were administered to 585 Chinese participants. The findings indicate that the intensity of dream experiences and the narrative content of dreams are useful for identifying individuals with clinically significant hysterical symptoms. Hysterical dissociation is better predicted by the Ego Ideal, Appetite-Instinctual, and Sexual scales of the Dream Themes Inventory, whereas hysterical conversion is better indicated by the Persecution scale. This finding is discussed in relation to the neuropsychological mechanisms of dreaming and delusions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

3.
Ecological succession is described by the 2nd law of thermodynamics. According to the universal law of the maximal energy dispersal, an ecosystem evolves toward a stationary state in its surroundings by consuming free energy via diverse mechanisms. Species are the mechanisms that conduct energy down along gradients between repositories of energy which consist of populations at various thermodynamic levels. The salient characteristics of succession, growing biomass production, increasing species richness and shifting distributions of species are found as consequences of the universal quest to diminish energy density differences in least time. The analysis reveals that during succession the ecosystem's energy transduction network, i.e., the food web organizes increasingly more effective in the free energy reduction by acquiring new, more effective and abandoning old, less effective species of energy transduction. The number of species does not necessarily peak at the climax state that corresponds to the maximum-entropy partition of species maximizing consumption of free energy. According to the theory of evolution by natural selection founded on statistical physics of open systems, ecological succession is one among many other evolutionary processes.  相似文献   

4.

Background and objectives

For viral infections conferring what is usually considered as permanent immunity, re-exposure to the pathogen due to contacts with infectious individuals might be critical for immunity boosting. A major example is represented by the varicella-zoster virus (VZV) where re-exposure is thought to lead to boosting of cell mediated immunity (CMI), which plays a protective role against the development of herpes zoster (HZ). Similar concerns have recently been raised also in relation to measles. However, while the first effective exposure, i.e. infection, has been the object of many studies, both theoretical and epidemiological, there has been no corresponding investigation of the re-exposure process.

Methodology and data

By combining basic concepts from deterministic and stochastic modelling of infection, we develop a basic model for quantifying the timing and number of re-exposures and, consequently, the potential for immune boosting at any given age. The model is then applied to measles, mumps and rubella (MMR) in the UK, and to varicella in Italy, using literature estimates of the pre-vaccination forces of infection.

Results

We supply analytical expressions for the expected number of lifetime re-exposures and for underlying age-patterns, including the average age at which the last re-exposure occurs. Based on updated estimates of the force of VZV infection, we show that the expected number of boosting opportunities of CMI might be in the range 2–3, which is consistent with recent findings about the development of herpes zoster. We also show that the estimate of the age at which the last re-exposure to VZV occurs is highly sensitive to the underlying form of age dependence of the force of infection.

Conclusions

Our results contribute to the study of the potential immunity boosting effect of re-exposures to an infective agent by quantifying the re-exposure process.  相似文献   

5.
Hydroxyapatite (HAp), the major inorganic component of hard tissues in vivo, was formed in/on a PVA gel. The HAp formation ratio depended on the reaction cycle number, but was independent of the alternate soaking period per cycle. The Ca/P molar ratio of HAp formed at 10 reaction cycles was very close to the theoretical value of HAp, 1.67. CHO-K1 cell adhesion, proliferation and maximum cell density on HAp plates were better on plates formed at two or five reaction cycles using 200 mM CaCl2 and 120 mM Na2HPO4 solutions than on plates formed under other conditions. Furthermore, the adhesion ratio of CHO-K1 cells on HAp plates formed at 10 reaction cycles was about 60% of those at two or five reaction cycles.  相似文献   

6.
The fate of 125I labeled antigen-antibody complexes in the first two hours after intravenous injection was followed in the spleen of mice by light and electron microscopic autoradiography. It appeared that AAC were phagocytized by granulocytes and by macrophages in the marginal zone and were present over the surface of lymphocytes in that area. By rinsing the spleen before fixation it could be shown that AAC were indeed bound to the lymphocyte membrane and not merely present in the blood plasma between the cells. The label was present in a spotty fashion or over a so-called uropod. The majority of labeled uropods (13 out of 17) pointed away from the follicle. From this it was inferred that these lymphocytes moved to and most probably into, the follicles. Inside the follicles, at 1 hour post injectionem, most of the label was associated with interfaces between lymphocytes. At 2 hours post injectionem there was a preferential localization over interfaces between lymphocytes and dendritic reticulum cells. It is conceivable that antigen that is introduced into the circulation is ultimately presented to dendritic reticulum cells in a complexed form with antibody, probably with complement, and with the B-cell receptor, since receptor shedding is a normal event following capping.  相似文献   

7.
利用马尔柯夫过程预测东陵区土地利用格局的变化   总被引:113,自引:10,他引:113  
徐岚  赵羿 《应用生态学报》1993,4(3):272-277
根据沈阳市东陵区3个时期遥感航片和地形图获得的土地利用类型数据,成功地确定了土地利用类型的转移概率,并用马氏链模型预测了该区土地利用类型变化趋势。结果表明,当前该区的土地利用格局正处于一种耕地逐渐减少,居民点工矿用地逐渐增加的变化状态,而且这种变化将持续很长时间,最后将达到以旱地20.66%、水田28.41%、居民点工矿用地37.42%、菜地6.15%、林地4.36%等为主要土地利用类型的稳定状态,形成一个城乡结合的新的土地利用格局。  相似文献   

8.
The baker's yeast process was optimised with a fuzzy logic controller, which is capable of detecting (with the respiratory quotient as indicator) and eliminating overdosage. The controller was developed to enable automatic modification of the set value for the respiratory quotient according to glucose concentration in the broth. With this controller, a cell yield of 55% (w/w) from glucose and a maximum specific growth rate of 0.16 h–1 were obtained.  相似文献   

9.
N. L. Wallin 《Human Evolution》2000,15(3-4):199-242
Musical experience and creativity are regarded to be largely depending on cultural conditions and hence on higher cognitive functions. True as this may be, there are, however, numerous responses to music-the urge to make music taken into account-which derive from deeper levels of the human organism, namely from arousing alternatively moderating vegetative and limbic functions. Although the behavioral intensity and quality emanating from such evolutionary early nervous structures may be affected by cultural influence, they still seem to be essentially independent. Similar specific responses to acoustical and/or motor patterned stimuli are found among some other higher vertebrates which like humans are equipped with sophisticated mechanisms for hearing, sound production and locomotion, well tuned to each other. However, it is even today an open question whether these manifestations of auditive-phonatory-locomotor abilities just are analogues or if they share a common evolutionary background. The current discussion on this matter has accumulated data which apparently support the latter view pointing to that sexual selection would be the common force, first suggested by Charles Darwin (153). Other, and still more recent data in genetics and neuroscience, may be interpreted as hints at that the common origin would be a more elemental organismic feature, a metabolic-homeostatic variable which due to its evolutionary strength eventually created the platform for a radiation of adaptations concerning species-specific patterned sounds and locomotions with a broad spectrum of tasks, among them sexual selection. This line of reasoning is here, under reference to recent biological data, made the basis for a hypothetical model of music as an expression of an early homeostatic feedback mechanism. Accordingly, in music there is a central variable, a “heart” or a “core”, which is not to be found exclusively in music but appears globally as a releasing mechanism for basic endocrine, autonomous and elementally cognitive functions. It is of acoustical or motoric nature, or of a combination of these characters, and is performed in repetitive trains of impulses. It is further assumed that the target of its operations is mainly proteins with a regulatory effect on the cellular and synaptic states. The principal representatives for these proteins are growth factors, especially the NGF which originally was regarded as a growth stimulator within the peripheral and sympathetical systems but which eventually appeared to be also a synergetic modulator of neuro-endocrine-immuno-reactions, i.e. of the three central homeostatic systems (5, 80). One can speculate that this variable is functionally active at an elemental level such that it has escaped to be knocked out by forceful “higher” and evolutionary younger factors (49:13). This hypothesis — that music has its roots within and is a part of a globally occurring natural acoustical-motoric stimulus, manifested in a great variety of auditory and motoric behavior in humans and among some other higher vertebrates — implies that humankind has developed this stimulus into a category of acoustical structures which oscillate round an instable point of equilibrium. Exactly such structures, not stochastic but neither too predictable, affect the organism mainly on a sensory-vegetative level (59, 102, 137, 151). They are in addition perceptionally optimal in creating cortical space-temporal neural patterns with strong interhemispheric coherence (110, 130). According to this scenario, music did not originate from a human need of communication or as an aspect of sexual selection. It emerged from elemental processes within the individual organism with the aspiration to maintain his bodily and mental fitness, thus on a pre-social level. What was beneficial to the single individual in his fight for survival, was good also for the group and its survival. Starting from that platform music has evolved in symbiosis with dance and play within a large spectrum of social functions, where sexual selection and ritual and autonomously aesthetical tasks got a focal role that increased over time and always was accompanied by emotional events. Behind, the ticking in the deep structure of music of this in cultural-ethical terms totally value-neutral archaic mechanism goes on without pause, contributing to the maintenance of an optimal functional balance in body and mind of the individual, and the group as well.  相似文献   

10.
This article describes the development of a high‐throughput process development (HTPD) platform for developing chromatography steps. An assessment of the platform as a tool for establishing the “characterization space” for an ion exchange chromatography step has been performed by using design of experiments. Case studies involving use of a biotech therapeutic, granulocyte colony‐stimulating factor have been used to demonstrate the performance of the platform. We discuss the various challenges that arise when working at such small volumes along with the solutions that we propose to alleviate these challenges to make the HTPD data suitable for empirical modeling. Further, we have also validated the scalability of this platform by comparing the results from the HTPD platform (2 and 6 μL resin volumes) against those obtained at the traditional laboratory scale (resin volume, 0.5 mL). We find that after integration of the proposed correction factors, the HTPD platform is capable of performing the process optimization studies at 170‐fold higher productivity. The platform is capable of providing semi‐quantitative assessment of the effects of the various input parameters under consideration. We think that platform such as the one presented is an excellent tool for examining the “characterization space” and reducing the extensive experimentation at the traditional lab scale that is otherwise required for establishing the “design space.” Thus, this platform will specifically aid in successful implementation of quality by design in biotech process development. This is especially significant in view of the constraints with respect to time and resources that the biopharma industry faces today. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 403–414, 2013  相似文献   

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