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Bo Feng 《人类交流研究》2009,35(1):115-129
Viewing supportive communication as a multistage process, the present study proposed and tested an integrated model of advice giving, which specifies three sequential moves in supportive interactions involving advice: emotional support, problem inquiry and analysis, and advice. Seven hundred and fifty‐two participants read and responded to a hypothetical scenario in which they received advice from a friend. Results of the study showed that advice that was offered following the moves of emotional support and problem inquiry and analysis was judged to be higher in quality than advice that did not follow this sequential pattern.  相似文献   
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Abstract: It is argued that the so-called principles of "strong centering" and "weak centering" central to the traditional Lewis-Stalnaker semantics for counterfactuals are both fallacious. A foundation for an alternative semantics without these prinsciples is outlined. The core idea is that the statistically normal worlds – rather than those worlds most qualitatively similar to the actual world – should serve as the semantical fulcrum.  相似文献   
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这篇论文在回顾通俗文学中道教神仙形象基础上,阐释了不同时期神仙形象的变化和基本特征,并对形成这些不同的神仙形象的社会及宗教背景进行了分析,指出道教的世俗化是造成通俗文学中神仙形象宗教色彩逐渐减弱,人性特征逐渐加强的根源.  相似文献   
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Discrimination of sensory signals is essential for an organism to form and retrieve memories of relevance in a given behavioral context. Sensory representations are modified dynamically by changes in behavioral state, facilitating context-dependent selection of behavior, through signals carried by noradrenergic input in mammals, or octopamine (OA) in insects. To understand the circuit mechanisms of this signaling, we characterized the function of two OA neurons, sVUM1 neurons, that originate in the subesophageal zone (SEZ) and target the input region of the memory center, the mushroom body (MB) calyx, in larval Drosophila. We found that sVUM1 neurons target multiple neurons, including olfactory projection neurons (PNs), the inhibitory neuron APL, and a pair of extrinsic output neurons, but relatively few mushroom body intrinsic neurons, Kenyon cells. PN terminals carried the OA receptor Oamb, a Drosophila α1-adrenergic receptor ortholog. Using an odor discrimination learning paradigm, we showed that optogenetic activation of OA neurons compromised discrimination of similar odors but not learning ability. Our results suggest that sVUM1 neurons modify odor representations via multiple extrinsic inputs at the sensory input area to the MB olfactory learning circuit.

Behavioral choices depend on discrimination among “sensory objects,” which are neural representations of multiple coincident sensory inputs, across a range of sensory modalities. For example, “odor objects” (Gottfried 2009; Wilson and Sullivan 2011; Gire et al. 2013) are represented in sparse ensembles of neurons, that are coincidence detectors of multiple parallel inputs from odor quality channels. This principle is used widely in animals, including in mushroom bodies (MBs), the insect center for associative memory (Masuda-Nakagawa et al. 2005; Honegger et al. 2011), and in the piriform cortex (PCx) of mammals (Stettler and Axel 2009; Davison and Ehlers 2011).The selectivity of sensory representations can be modulated dynamically by changes in behavioral state, allowing an animal to learn and respond according to perceptual task. In mammals, the noradrenergic system originating in the locus coeruleus (LC) is implicated in signaling behavioral states such as attention, arousal and expectation (Aston-Jones and Cohen 2005; Sara and Bouret 2012).In insects, octopamine (OA), structurally and functionally similar to noradrenalin (NA) in mammals (Roeder 2005), can mediate changes in behavioral state that often promote activity; for example, sensitization of reflex actions in locusts (Sombati and Hoyle 1984), aggressive state in crickets (Stevenson et al. 2005), initiation and maintenance of flight state (Brembs et al. 2007; Suver et al. 2012), and enhanced excitability of Drosophila motion detection neurons during flight (Strother et al. 2018). Another role of OA is as a reward signal: A single OA neuron, VUMmx1, mediates the reinforcing function of unconditioned stimulus in the honeybee proboscis extension reflex (Hammer 1993; Hammer and Menzel 1998; Menzel 2012). In Drosophila, acquisition of appetitive memory is impaired in TβH mutants, unable to synthesize OA (Schwaerzel et al. 2003), and activation of OA neurons can substitute reinforcing stimulus in appetitive learning (Schroll et al. 2006). Moreover, OA receptors are necessary for reward learning in Drosophila (Burke et al. 2012) and crickets (Matsumoto et al. 2015).To understand the neural mechanisms of OA in higher order sensory discrimination, we used the simple sensory “cortex” of larval Drosophila, the calyx, which is the sensory input region of the mushroom bodies (MBs), the insect memory center. Here, each MB neuron (Kenyon cell [KC]) typically arborizes in several glomeruli, most of which are organized around the terminus of an olfactory projection neuron (PN); KCs thus combinatorially integrate multiple sensory input channels (Masuda-Nakagawa et al. 2005) and are coincidence detectors of multiple inputs. The APL provides inhibitory feedback (Lin et al. 2014; Masuda-Nakagawa et al. 2014) and helps to maintain KC sparse responses and odor selectivity (Honegger et al. 2011), analogous to inhibition in the mammalian PCx (Poo and Isaacson 2009; Stettler and Axel 2009; Gire et al. 2013). Thus, odors are represented as a sparse ensemble of KCs that are highly odor selective, a property beneficial for memory (Olshausen and Field 2004).In addition, the larval MB calyx is innervated by two OA neurons, sVUMmd1 and sVUMmx1, ventral unpaired medial neurons with dendritic fields originating in the mandibular and maxillary neuromeres, respectively, of the SEZ in the third instar larva (Selcho et al. 2014). sVUMmd1 and sVUMmx1 are named as OANa-1 and OANa-2, respectively, in the EM connectomic analysis of a 6-h first instar larva (Eichler et al. 2017; Supplemental Fig. 3 of Saumweber et al. 2018). These sVUM1 neurons also innervate the first olfactory neuropile of the antennal lobe (AL). This pattern of innervation is conserved in other insects, for example, the dorsal unpaired median (DUM) neurons in locusts (for review, see Bräunig and Pflüger 2001), the VUMmx1 neuron in honeybees (Hammer 1993; Schröter et al. 2007), and OA-VUMa2 neurons in adult Drosophila (Busch et al. 2009). In adult Drosophila, OA-VUMa2 neurons also show a dense innervation of the lateral horn, implicated in innate behaviors (Busch et al. 2009). The widespread innervation of the insect olfactory neuropiles also resembles the widespread NA innervation of mammalian olfactory processing areas, such as the olfactory bulb, and piriform cortex, by LC neurons originating in the brainstem.We characterized the innervation pattern and synaptic targets of sVUM1 neurons in the calyx, with MB intrinsic and also extrinsic neurons, the localization of the OA receptor Oamb in the calyx circuit, and the impact of sVUM1 neuron activation on behavioral odor discrimination. For this we used an appetitive conditioning paradigm, and tested the ability of larvae to discriminate between similar odors, as opposed to dissimilar odors. Since the larval connectome is based on a single brain, at first instar stage before octopaminergic connections have become as extensive as at third instar, and to obtain a comprehensive understanding of the synaptic targets of sVUM1s in the third-instar larval calyx, we extended our analysis to previously unanalyzed connectivity of VUM1s, to APL and PNs. Further, we combined light microscopy of third-instar larvae with the connectome described by Eichler et al. (2017).We find that sVUM1 neurons in third-instar larvae contact all the major classes of calyx neuron to some degree, consistent with EM synaptic analysis of the 6-h larva (Eichler et al. 2017). A GFP fusion of the OA receptor Oamb is localized in the terminals of PNs, and activating a subset of five SEZ neurons, including sVUM1 neurons, can affect discrimination of similar odors, without affecting underlying olfactory learning and memory ability. We suggest a broad modulatory effect of sVUM1 neurons in the calyx, including a potential role in modulating PN input at the second synapse in the olfactory pathway.  相似文献   
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明末西方传教士出于抬高西方宗教、传播宗教福音的政治考量,翻译出版了大量的西方科学著作.西方演绎逻辑思想正是在这样的背景下,得以在明末被翻译介绍到国内.这其中,尤以利玛窦推动译介的<几何原本>及傅汎际推动译介的<名理探>最为知名.这其中,自然也毫无例外地带有浓厚的为宗教传道先行的色彩.但也在客观上帮助了中国人了解西方演绎逻辑的思想,带动了其后国内学界对挖掘本土以名辩学为基础的中国逻辑史研究的热潮.  相似文献   
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继承语是移民社会的特殊现象.在英语为通用语言的美国社会中,继承语学习者和继承语之间存在着亲缘关系.本文回顾了近年来继承语在美国的发展,指出继承语项目能够维护语言生态,顺应人口变化,促进族裔认同,调整语言关系,将成为美国语言教育的新方向.  相似文献   
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