Colcemid sensitivity of fission yeast and the isolation of colcemid-resistant mutants

Cell division of the fission yeast, Schizosaccharomyces pombe, is reversibly inhibited by the antimitotic agent Colcemid (N-deacetyl-N-methylcolchicine) in nutrient medium. Cell growth continiues until all cells become nonseparating cell doublets in a V configuration. Mutants have been isolated capable of uninhibited growth in the presence of concentrations of Colcemid mycostatic for the parent strain.     

Curvilinear motion in the absence of external forces: naive beliefs about the motion of objects

University students were asked to draw the path a moving object would follow in several different situations. Over half of the students, including many who had taken physics courses, evidenced striking misconceptions about the motion of objects. In particular, many students believed that even in the absence of external forces, objects would move in curved paths.     

Delay of gratification in children

To function effectively, individuals must voluntarily postpone immediate gratification and persist in goal-directed behavior for the sake of later outcomes. The present research program analyzed the nature of this type of future-oriented self-control and the psychological processes that underlie it. Enduring individual differences in self-control were found as early as the preschool years. Those 4-year-old children who delayed gratification longer in certain laboratory situations developed into more cognitively and socially competent adolescents, achieving higher scholastic performance and coping better with frustration and stress. Experiments in the same research program also identified specific cognitive and attentional processes that allow effective self-regulation early in the course of development. The experimental results, in turn, specified the particular types of preschool delay situations diagnostic for predicting aspects of cognitive and social competence later in life.     

What is so disturbing about Jan Smiley's A Thousand Acres?

Jane Smiley's award winning and disturbing novel, A Thousand Acres, invites a critical appraisal of a popular assumption for proponents of sustainable agriculture: that family farming and sustainable agriculture are (at least indirectly) mutually reinforcing. This process begins with a plot that presents an Iowa multigenerational farm family headed by an acutely dominant father. Consequences of this dominance include subjugation of everyone involved with the farming operation, varieties of abuse of the daughters, and primitive non-environmental farming. Also in the novel three structural components of the family farm/rural setting aggravate the nightmarish situation: multigenerational participation in one farming operation, children remaining on the farm, uninterrupted, into adulthood, and the power of community appearances. It is argued that these components contribute not only to the family problems, but also to making the poor farming that emerges in this family not very coincidental. This analysis, if correct, raises many issues about farm structure and farming practices. They include how the younger generation(s) of family farm structures cope with their situations, whether aspects of family farms skew who decides to remain to farm, family farm ownership and transfer structure, how well farmers understand their own farms, and the case for voluntarism regarding environmental issues in farming. One theme throughout the essay is that the novel enables better recognition and appreciation of the subtle relationship between family problems and farming practices.     

Pure reasoning in 12-month-old infants as probabilistic inference

Many organisms can predict future events from the statistics of past experience, but humans also excel at making predictions by pure reasoning: integrating multiple sources of information, guided by abstract knowledge, to form rational expectations about novel situations, never directly experienced. Here, we show that this reasoning is surprisingly rich, powerful, and coherent even in preverbal infants. When 12-month-old infants view complex displays of multiple moving objects, they form time-varying expectations about future events that are a systematic and rational function of several stimulus variables. Infants' looking times are consistent with a Bayesian ideal observer embodying abstract principles of object motion. The model explains infants' statistical expectations and classic qualitative findings about object cognition in younger babies, not originally viewed as probabilistic inferences.     

高校图书馆在农村留守学生“补偿教育”中的作为

农村留守学生在全社会同龄学生的教育中处于弱势地位,他们的教育问题是当前教育界面临的突出难题之一,如不及时解决,他们的弱势地位还会持续下去,影响他们的一生甚至还会遗传下去。高校图书馆作为一个不可或缺的教育阵地,必须突破现有的瓶颈,拓宽服务对象和范围,创新服务措施,对农村留守学生进行＂补偿教育＂,从而在创建和谐社会中尽一份力。     

Scale errors offer evidence for a perception-action dissociation early in life

We report a perception-action dissociation in the behavior of normally developing young children. In adults and older children, the perception of an object and the organization of actions on it are seamlessly integrated. However, as documented here, 18- to 30-month-old children sometimes fail to use information about object size and make serious attempts to perform impossible actions on miniature objects. They try, for example, to sit in a dollhouse chair or to get into a small toy car. We interpret scale errors as reflecting problems with inhibitory control and with the integration of visual information for perception and action.     

Rule learning by rats

Using rules extracted from experience to solve problems in novel situations involves cognitions such as analogical reasoning and language learning and is considered a keystone of humans' unique abilities. Nonprimates, it has been argued, lack such rule transfer. We report that Rattus norvegicus can learn simple rules and apply them to new situations. Rats learned that sequences of stimuli consistent with a rule (such as XYX) were different from other sequences (such as XXY or YXX). When novel stimuli were used to construct sequences that did or did not obey the previously learned rule, rats transferred their learning. Therefore, rats, like humans, can transfer structural knowledge from sequential experiences.     

"人"与制度设计--从两个事例谈起

从制度设计与"人"的关系的角度,探讨了有关制度设计的问题.指出由于人极可能会按自己的自主行为选择来行动,因此,制度要求的行为模式与人的现实行动选择可能会发生冲突.因而,鉴于人的行为与制度运作的高度相关性,为避免因这种冲突而可能会导致的制度失灵,制度设计必须重视对"人"的考察,并将"人"的因素纳入制度设计的框架,以在人的自觉行为的带动下,实现自身的良性运作.     

Measurement scales on the continuum

In a seminal article in 1946, S. S. Stevens noted that the numerical measures then in common use exhibited three admissible groups of transformations: similarity, affine, and monotonic. Until recently, it was unclear what other scale types are possible. For situations on the continuum that are homogeneous (that is, objects are not distinguishable by their properties), the possibilities are essentially these three plus another type lying between the first two. These types lead to clearly described classes of structures that can, in principle, be incorporated into the classical structure of physical units. Such results, along with characterizations of important special cases, are potentially useful in the behavioral and social sciences.     

Japanese quail can learn phonetic categories

Japanese quail (Coturnix coturnix) learned a category for syllable-initial [d] followed by a dozen different vowels. After learning to categorize syllables consisting of [d], [b], or [g] followed by four different vowels, quail correctly categorized syllables in which the same consonants preceded eight novel vowels. Acoustic analysis of the categorized syllables revealed no single feature or pattern of features that could support generalization, suggesting that the quail adopted a more complex mapping of stimuli into categories. These results challenge theories of speech sound classification that posit uniquely human capacities.     

农民工“留守子女”教育问题思考

“留守子女”教育问题是伴随着农民工的出现而出现的。大量的农民工留守子女面临着教育危机,他们心理压力大,家教薄弱,少年犯罪现象时有发生。应改革户籍制度,让有条件的农民工将子女带入城市,就近入学;搞好农村义务教育和幼儿教育;留守子女父母应经常与临时监护人、学校及老师沟通。     

Word learning in a domestic dog: evidence for "fast mapping"

During speech acquisition, children form quick and rough hypotheses about the meaning of a new word after only a single exposure-a process dubbed "fast mapping." Here we provide evidence that a border collie, Rico, is able to fast map. Rico knew the labels of over 200 different items. He inferred the names of novel items by exclusion learning and correctly retrieved those items right away as well as 4 weeks after the initial exposure. Fast mapping thus appears to be mediated by general learning and memory mechanisms also found in other animals and not by a language acquisition device that is special to humans.     

Contrast tuning in auditory cortex

The acoustic features useful for converting auditory information into perceived objects are poorly understood. Although auditory cortex neurons have been described as being narrowly tuned and preferentially responsive to narrowband signals, naturally occurring sounds are generally wideband with unique spectral energy profiles. Through the use of parametric wideband acoustic stimuli, we found that such neurons in awake marmoset monkeys respond vigorously to wideband sounds having complex spectral shapes, preferring stimuli of either high or low spectral contrast. Low contrast-preferring neurons cannot be studied thoroughly with narrowband stimuli and have not been previously described. These findings indicate that spectral contrast reflects an important stimulus decomposition in auditory cortex and may contribute to the recognition of acoustic objects.     

Molecular characterization of the human beta 3-adrenergic receptor

Since the classification of beta-adrenergic receptors (beta-ARs) into beta 1 and beta 2 subtypes, additional beta-ARs have been implicated in the control of various metabolic processes by catecholamines. A human gene has been isolated that encodes a third beta-AR, here referred to as the "beta 3-adrenergic receptor." Exposure of eukaryotic cells transfected with this gene to adrenaline or noradrenaline promotes the accumulation of adenosine 3',5'-monophosphate; only 2 of 11 classical beta-AR blockers efficiently inhibited this effect, whereas two others behaved as beta 3-AR agonists. The potency order of beta-AR agonists for the beta 3-AR correlates with their rank order for stimulating various metabolic processes in tissues where atypical adrenergic sites are thought to exist. In particular, novel beta-AR agonists having high thermogenic, antiobesity, and antidiabetic activities in animal models are among the most potent stimulators of the beta 3-AR.     

中国传统佛教与日本“批判佛教”

从20世纪初开始,一直有日本学者质疑中国传统佛教并非真佛教,最后酝酿出"批判佛教"的思潮。他们在误会《阿含经》缘起法的前提下,强力否定以如来藏之修证为中心的中国传统佛教。影响所及,台湾佛学研究出现了日本化的倾向。事实上,如来藏并不违背《阿含经》。《阿含经》的"我"和"识界"等名相,以及入胎识、持身识等观念,说的都是如来藏,也是实质上的大乘法。     

Memory's penumbra: episodic memory decisions induce lingering mnemonic biases

How do we decide if the people we meet and the things we see are familiar or new? If something is new, we need to encode it as a memory distinct from already stored episodes, using a process known as pattern separation. If familiar, it can be used to reactivate a previously stored memory, by a process known as pattern completion. To orchestrate these conflicting processes, current models propose that the episodic memory system uses environmental cues to establish processing biases that favor either pattern separation during encoding or pattern completion during retrieval. To assess this theory, we measured how people's memory formation and decisions are influenced by their recent engagement in episodic encoding and retrieval. We found that the recent encoding of novel objects improved subsequent identification of subtle changes, a task thought to rely on pattern separation. Conversely, recent retrieval of old objects increased the subsequent integration of stored information into new memories, a process thought to rely on pattern completion. These experiments provide behavioral evidence that episodic encoding and retrieval evoke lingering biases that influence subsequent mnemonic processing.     

Biogenic amines and control of melanophore stimulating hormone release

Release of melanophore stimulating hormone (MSH) from the vertebrate pars intermedia is under inhibitory control by the hypothalamus. Removal of the rat pituitary or the neurointermediate lobe of the frog (Rana pipiens) to in vitro incubation medium results in rapid uninhibited release of MSH. This secretion is inhibited by norepinephrine, epinephrine, phenylephrine, and dopamine, and the inhibition is antagonized by alpha-adrenergic receptor blocking agents. Isoproterenol stimulation of MSH secretion from isolated glands is blocked by pro-pranolol, a beta-adrenergic receptor antagonist. These results implicate dopaminergic or classical alpha-adrenergic receptors (or both) in inhibition of MSH release by catecholamines, and implicate beta-adrenergic receptors in stimulation of MSH release by the bioamines.     

农业转移人口子女语言状况与城市融合——以合肥市调查为例

农业转移人口子女进入城市后所面临的语码选择、家庭语言规划等语言问题与该群体的城市融合之间具有一定的相关性。对合肥两所小学的调查发现,普通话在该群体语言使用和家庭语言规划中具有较高的取向度,而合肥话与该群体的城市融合之间具有更强相关性。语言取向度高的原因在于合肥言语社区中普通话社区的互动人口和设施建设更加完善,而合肥话与城市融合的相关性更强则体现了语言认同在城市融合中的重要作用,也证明了提高城市方言取向度是促进城市融合的有效途径。     

用代数法解析一些英语难句的汉译问题

大学英语教育涉及到非英语专业的学生。理工科的学生善于逻辑思维,喜欢用数学公式来解决一些形象思维问题。把逻辑思维的方式运用到语言学习的翻译中,尝试性地用代数法从四个方面用译例来解析一些英语难句的汉译问题。