肥胖成因的解释——基于食物奖赏研究的视角

肥胖的形成和发展受生物、心理和社会因素的共同作用,其中食物奖赏对肥胖的产生有重要的作用。食物是一种自然奖赏,它指机体天生对食物的渴望和依赖。食物奖赏包括"wanting"、"liking"以及"learningreinforcement"三个成分,每个成分由相应的神经通路表征。食物奖赏调控机体的摄食行为并以此调控体重变化。目前,关于肥胖与食物奖赏关系的理论模型主要有刺激—敏感化理论、奖赏过度理论以及奖赏不足理论。采用横断面设计、前瞻研究设计和纵向被试内重复测量设计,使用食物图片线索和直接给予美味奶昔的技术方法,人类脑成像研究从不同侧面为以上三个理论模型提供了证据。除此之外,食物奖赏还受基因的调控。目前,研究者关注较多的是多巴胺D2受体基因Taq IA rs1800497的多态性和FTO基因rs9939609的多态性对食物奖赏及体重改变的调控。     

An explanation of orthogonal S-R compatibility effects that vary with hand or response position: the end-state comfort hypothesis

This study presents an explanation of orthogonal stimulus-response compatibility (SRC) effects that vary with hand or response location: the end-state comfort hypothesis. It posits that responses are spatially transformed and cognitively mapped onto the stimulus dimension according to relative hand posture, thereby mediating the pattern of facilitation and interference in response selection. In the first three experiments, we investigated the eccentricity effect, finding that responses by the left hand in left hemispace are faster with up-left/down-right mapping while responses by the right hand in right hemispace are faster with up-right/down-left mapping (Michaels & Schilder, 1991, Experiment 1). The endstate comfort hypothesis correctly predicted that the eccentricity effect occurred irrespective of the relative position of the stimulus and response device in the sagittal plane (Experiments 1 and 2), and that it reversed when the stimulus-response set was reversed, regardless of the relative position of the stimulus and response device in the fronto-parallel plane (Experiments 2 and 3). Experiment 4 shows a new orthogonal SRC effect that was predicted by the end-state comfort hypothesis. Our results are inconsis tent with other explanations, such as the virtual-lines hypothesis and the salient-features hypothesis.     

The development of procedural knowledge: An alternative explanation for chronometric trends of mental arithmetic

In a review of the Chronometrie literature, M. H. Ashcraft (Developmental Review, 1982, 2, 213–236) concluded that the development of number fact efficiency is due to a shift from relying on procedural knowledge such as counting to relying on declarative knowledge (a stored network of facts). This model assumes that all procedural processes are slow or remain slow, which is probably not the case. An alternative account posits that the key change in number fact efficiency involves a shift from slow counting procedures to principled procedural knowledge. As rules, heuristics, and principles become more familiar and interconnected, their use, for example, in producing the number facts becomes more automatic. The use of such procedural knowledge would be cognitively more economical than storing individual facts in long-term memory. Finally, existing Chronometric data can readily be interpreted in terms of this alternative model.     

Repetition priming of face gender judgments: An instance based explanation

Earlier studies of repetition priming using faces have been interpreted as indicating that such effects are confined to the processing of known faces. The experiment reported here employed eight rather than the more usual two presentation trials and required subjects to make gender decisions (is it a male or is it a female face?) to both familiar and unfamiliar faces. This allowed the currently favored recognition unit theories of face processing to be compared with the Logan (1988) instance model. Equivalent repetition priming effects were observed for both familiar and unfamiliar faces and were well fitted by power functions. It is argued that the findings are consistent with the strong predictions made by Logan's model and pose problems for recognition unit based theories.     

Repetition priming of face gender judgments: An instance based explanation

Earlier studies of repetition priming using faces have been interpreted as indicating that such effects are confined to the processing of known faces. The experiment reported here employed eight rather than the more usual two presentation trials and required subjects to make gender decisions (is it a male or is it a female face?) to both familiar and unfamiliar faces. This allowed the currently favored recognition unit theories of face processing to be compared with the Logan (1988) instance model. Equivalent repetition priming effects were observed for both familiar and unfamiliar faces and were well fitted by power functions. It is argued that the findings are consistent with the strong predictions made by Logan's model and pose problems for recognition unit based theories.     

儒家差异思想阐微

Difference is a category of relationship lying between identity and non-identity, and equality and inequality. This concept is both the Confucian reflection of the real relationship between things in the world and the value ideal of Confucianism. The Confucian idea of difference, embodied in the view of human relationships, of world, and of nature, seeks to build a rational order based on difference, so as to reach a harmonious, united and ideal state. Confucians in the past dynasties continually interpreted difference and raised it to the level of ontology, enriching the system of Confucianism. Translated by Yan Xin from Zhexue Yanjiu 哲学研究 (Philosophical Studies), 2006, (3): 32–37     

An erotetic approach to explanation by specification

In earlier publications of the first author it was shown that intentional explanation of actions, functional explanation of biological traits and causal explanation of abnormal events share a common structure. They are called explanation by specification (of a goal, a biological function, an abnormal causal factor, respectively) as opposed to explanation by subsumption under a law. Explanation by specification is guided by a schematic train of thought, of which the argumentative steps not concerning questions were already shown to be logically valid (elementary) arguments.Independently, the second author developed a new, inferential approach to erotetic logic, the logic of questions. In this approach arguments resulting in questions, with declarative sentences and/or other questions as premises, are analyzed, and validity of such arguments is defined.In the present paper it is shown that all four kinds of erotetic argumentative steps occurring in the train of thought of explanation by specification are valid arguments in the sense of inferential erotetic logic. Hence, in view of the fact that the other argumentative steps were already shown to be valid, it may be concluded that the logical structure of explanation by specification can be as well-established as that of explanation by nomological subsumption. Moreover, explanation by specification provides some illustrations of the applicability of erotetic logic in everyday life and some empirical sciences.     

Decision noise: An explanation for observed violations of signal detection theory

In signal detection theory (SDT), responses are governed by perceptual noise and a flexible decision criterion. Recent criticisms of SDT (see, e.g., Balakrishnan, 1999) have identified violations of its assumptions, and researchers have suggested that SDT fundamentally misrepresents perceptual and decision processes. We hypothesize that, instead, these violations of SDT stem from decision noise: the inability to use deterministic response criteria. In order to investigate this hypothesis, we present a simple extension of SDT—the decision noise model—with which we demonstrate that shifts in a decision criterion can be masked by decision noise. In addition, we propose a new statistic that can help identify whether the violations of SDT stem from perceptual or from decision processes. The results of a stimulus classification experiment—together with model fits to past experiments—show that decision noise substantially affects performance. These findings suggest that decision noise is important across a wide range of tasks and needs to be better understood in order to accurately measure perceptual processes.     

An explanation of conservatism in the bookbag-and-pokerchips situation

An experiment is described in which subjective probability revisions were obtained in a standard probability estimation task, the ‘bookbag-and-pokerchips’situation. Three aspects of probability revision were examined: conservatism, sequential effects, and coherence. Under two experimental conditions, the conservatism effect obtained was closely related to subjects' use of a simple strategy. A recency effect was also obtained. Coherence of the probability estimates was excellent. Conditions under which the observed strategy leads to conservatism are explored and previously published results are reconsidered in the light of this strategy. Conservatism in the bookbag- and-pokerchips situation is explained as an artefact of subjects' strategies     

The paradox of happiness: towards an alternative explanation

There is a common empirical finding in many countries that substantial increases in real per capita income do not correspond to equivalent increases of individual happiness. These findings have puzzled many economists that some have called the “paradox of happiness”. There have been a number of explanations regarding this paradox. This paper attempts to tackle the paradox of happiness by employing the idea of hierarchical choice. The hierarchical approach implies that there are some basic human needs which must be satisfied before non-basic needs come into the picture. The paper argues that the hierarchical structure of needs implies that the satisfaction of basic needs provides substantial increases to individual happiness compared to the subsequent satisfaction of secondary needs. This might also be an alternative explanation of empirical findings showing a positive relationship between income and happiness up to certain level of income. It can also be combined with existing explanations of the paradox and thus enhance our understanding of the issue.

Statistical explanation in physics: The Copenhagen interpretation

The statistical aspects of quantum explanation are intrinsic to quantum physics; individual quantum events are created in the interactions associated with observation and are not describable by predictive theory. The superposition principle shows the essential difference between quantum and non-quantum physics, and the principle is exemplified in the classic single-photon two-slit interference experiment. Recently Mandel and Pfleegor have done an experiment somewhat similar to the optical single-photon experiment but with two independently operated lasers; interference is obtained even with beam intensity so small that only one photon is in the apparatus at a time. The result can be understood in terms of the superposition of states; or, in terms of the Uncertainty Principle, which is found to forbid the determination of which of the two lasers is the source of a given photon (if conditions for interference are to obtain). The Mandel-Pfleegor experiment gives a physical argument against the continuous localization of a photon that is assumed in the hidden variable theories and therefore gives further support for the generally accepted view that an observed entity (observed state) is created in the observation event. This aspect of quantum physics implies a subjectivism on the level of individual quantum-level occurrences, since there is in quantum theory no basis for asserting the existence of the event independently of observation of it. Extension of this subjectivism to large scale, non-quantum phenomena falls within the principles of quantum theory; counter considerations that argue against such an extension are noted.     

An explanation of the indentation size effect in ceramics

Abstract

A quantitative model is proposed to explain the indentation size effect (ISE) often observed in the hardness response of hard brittle materials, namely that hardness is observed to increase with decreasing indentation size. The model is based on a mixed elastic/plastic materials deformation response whereby plastic deformation occurs in a discrete manner progressively to relieve stresses created by elastic flexure of the surface at the edges of the indentation. During unloading of the indenter, recovery of the elastic increment of deformation, which precedes each new band of plastic deformation, results in the indentation appearing smaller than expected, particularly as the indentation sizes decrease to approach the scale of the plastic deformation band spacing. The model fits observed experimental data well and analysis of hardness/size data in this way is shown to allow both a bulk hardness value and a characteristic deformation band scale to be calculated for a given sample.     

《恒先》义释——思想史视野下的一种解读

Hengxian, one of the bamboo books of the Chu State during the Warring States Period that is kept in the Shanghai Museum, was collected by the museum in 1994, and is an important piece of literature that discusses cosmic issues prior to Huainanzi. Based on Li Ling’s work on the text, as well as hermeneutic work by some other scholars, this essay represents another attempt to determine the words and meanings of the Hengxian, with a focus on its cosmological commentary. Translated by Huang Deyuan from Xi’an Jianzhu Keji Daxue Xuebao 西安建筑科技大学学报 (Journal of Xi’an University of Arch & Tech), 2007, (1): 1–8