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色音 《广西民族大学学报》2014,(6):31-36
治病是北方少数民族萨满的主要职能之一。在信仰萨满教的民族中萨满往往充当民间医生的角色。萨满医术是一种精神医术和心灵医术。萨满主要是治心因性的精神疾病,其主要治疗手段也是一种心理治疗。在萨满医术中包含着现代精神医学中使用的一些治疗方法和治愈机制。萨满的精神医术之本质在于通过各种方式使患者的心理得到平衡,与此同时让患者振作起来,对自己的病情持乐观的态度,确立战胜病魔的信心。萨满精神医术就是一种典型的宗教性心理——生理调控术。对萨满医术,应从心理人类学、医学人类学、宗教人类学等多种角度进行研究,这样才能够得出比较全面而相对正确的结论。 相似文献
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Derek Bunn 《Journal of forecasting》1989,8(3):161-166
This paper comprises an editorial review for the Special Issue on Combining Forecasts. It gives a background to the current growth of interest in this topic and speculates upon some of the reasons for this popularity. Some of the main methodological issues in practice are also described. 相似文献
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Mycorrhizae are common plant-fungal symbioses occurring in most land plants. Despite their ubiquity, little is known about the distribution of arbuscular mycorrhizae (AM) in extreme environments. We surveyed for the presence of AM in thermal sites in Yellowstone National Park (YNP) where soils are characterized by extreme pHs, elevated temperatures, and toxic element concentrations. Plants at 5 sites, growing in soils with rooting-zone temperatures up to 48°C and soil pH values as low as 3.4, were mycorrhizal (colonization levels from 4% to 34%). Soils from a sparsely vegetated thermal area and an adjacent, continuously vegetated transition area differed significantly in rooting-zone temperature (35°C vs. 26°C), acidity (pH 3.8 vs. 5.4), electrical conductivity (2.22 vs. 0.49 mmhos cm -1 ), Fe (181.3 vs. 48.5 mg kg -1 ),Mn (7.2 vs. 98.2 mg kg -1 ), and Zn (2.3 vs. 4.5 mg kg -1 ). Mycorrhizal infectivity potential (MIP) was 77% greater in the transition soils, with colonization levels of 26% and 46% in thermal and transition soils, respectively. Furthermore, colonization of Agrostis scabra , Dichanthelium lanuginosum , and Mimulus guttatus was found to be consistently high throughout the growing season (from 48% to 72%). It is possible that AM are essential for plant life on the edge of thermal areas, and that either or both symbionts are specifically adapted to their environment. Further research is required to elucidate AM function in and specific adaptations to YNP's thermal areas. 相似文献
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Haemoglobin is the prototype of an allosteric protein in which cooperative behaviour depends on interaction between unlike subunits. Here we present haematological and biochemical evidence that electrostatic interactions are an important determinant of haemoglobin assembly. Individuals heterozygous for positively charged beta-globin variants have a significantly lower proportion of abnormal haemoglobin than those with negatively charged variants. Moreover, these differences become more pronounced when alpha-thalassaemia is also present. Kinetic experiments using isolated chains indicate that the rate of assembly of the heterotetramer is influenced by alterations in surface charge. A simple electrostatic model is proposed in an attempt to explain these haematological and experimental findings. 相似文献
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This paper proposes an approach that models and forecasts sales through a flexible parametric response function (multifunctional), allowing for differentiated behavioural assumptions of the response determinants to be specified, and uses neural network modelling as a re‐specification tool for the response model in order to improve forecasting performance. An initial experiment on a sample of sales data demonstrates feasibility and gives comparative insights via alternative model specifications. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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The Forecasting Performance of a Finite Mixture Regime‐Switching Model for Daily Electricity Prices
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Forecasting prices in electricity markets is a crucial activity for both risk management and asset optimization. Intra‐day power prices have a fine structure and are driven by an interaction of fundamental, behavioural and stochastic factors. Furthermore, there are reasons to expect the functional forms of price formation to be nonlinear in these factors and therefore specifying forecasting models that perform well out‐of‐sample is methodologically challenging. Markov regime switching has been widely advocated to capture some aspects of the nonlinearity, but it may suffer from overfitting and unobservability in the underlying states. In this paper we compare several extensions and alternative regime‐switching formulations, including logistic specifications of the underlying states, logistic smooth transition and finite mixture regression. The finite mixture approach to regime switching performs well in an extensive, out‐of‐sample forecasting comparison. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献