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1.
Computer generated textures are used to examine the recognition of pictorial textures and their edges by supervised learning. Since the recognition of texture at a given spot of the image involves measurements within a certain neighborhood of this spot, misclassification occurs at the edge between different textures, as was shown in Part 1. The edge enhancement procedures do also not produce a sharp edge. Based on some psychooptical evidence, a propagation operator is utilized to define the edges. First, the textures are classified only in those regions where a high level of confidence exists, the rest of the picture being marked as unrecognized. Second, the unrecognized picture elements adjoining a recognized spot are given its class, thus enlarging the recognized area. This process is repeated a few times, the limit being the propagation of results over an area greater than the neighborhood within which the texture parameters were measured in the first instance. The procedure yields welldefined edges at the proper locations.  相似文献   

2.
There is some evidence to suggest that undergraduate biology students need to be given more opportunities for reflection in their education. Some argue that computer-based learning packages may be able to offer such opportunities. This paper presents four different approaches to defining what reflection is and how it can be promoted. These approaches are then used to discuss and review the different ways in which computer-based tutorials can be used to promote lateral thinking. An example of a web-based biology tutorial called ‘How Now Mad Cow’ is described and preliminary evaluation results are presented, in order to illustrate how students may be encouraged to reflect and what factors may influence that. Finally, the role of the tutor in enspiring students to reflect while using computer-based tutorials is discussed. This distinguishes between the role of the tutor in designing a computer-based tutorial, and the role of the tutor in determining and facilitating how a student uses a tutorial once it has been designed.  相似文献   

3.
The capability of Ctenanthe setosa (Rosc.) Eichler (Marantaceae), pre-exposed to severe drought stress, of adaptation to a new drought conditions was investigated. C. setosa unstressed plants were exposed to drought period of 70 days. These plants were named as primary-stress plants (PS). They were trimmed, and new plants were produced from their rhizomes. New growing plants were named as post-stress emerging (PSE) plants. It was observed that leaf area and petiole length of PSE plants were reduced, as compared to unstressed plants. When PSE plants were exposed to a second drought-stress cycle, it was determined that the degree of their leaf rolling was higher but their relative water content (RWC) was less than these parameters of PS plants during drought period. However, at the 81% rolling degree, RWC in PSE plants was higher than in PS plants. Consequently, it can be said that the PSE plant were more resistant to a new drought stress than unstressed and PS plants. In the leaves of PSE plants, which were exposed to a second drought-stress period, the content of soluble protein decreased in the early period of drought, but increased in the later periods. Also, the content of reducing sugar in PSE plants gradually decreased during the stress period. Proline content increased markedly during drought period, whereas peroxidase activity increased up to the 60th day and then decreased. This text was submitted by the authors in English.  相似文献   

4.
In the presented review given literature and results of own studies of dynamics of electrical characteristics of neurons, which change are included in processes both an elaboration of learning, and retention of the long-term memory. Literary datas and our results allow to conclusion, that long-term retention of behavioural reactions during learning is accompanied not only by changing efficiency of synaptic transmission, as well as increasing of excitability of command neurons of the defensive reflex. This means, that in the process of learning are involved long-term changes of the characteristics a membrane of certain elements of neuronal network, dependent from the metabolism of the cells. see text). Thou phenomena possible mark as cellular (electrophysiological) correlates of long-term plastic modifications of the behaviour. The analyses of having results demonstrates an important role of membrane characteristics of neurons (their excitability) and parameters an synaptic transmission not only in initial stage of learning, as well as in long-term modifications of the behaviour (long-term memory).  相似文献   

5.
6.
Approach and avoidance are two behavioral responses that make people tend to approach positive and avoid negative situations. This study examines whether postural behavior is influenced by the affective state of pictures. While standing on the Wii™ Balance Board, participants viewed pleasant, neutral, and unpleasant pictures (passively viewing phase). Then they had to move their body to the left or the right (lateral movement phase) to make the next picture appear. We recorded movements in the anterior-posterior direction to examine approach and avoidant behavior. During passively viewing, people approached pleasant pictures. They avoided unpleasant ones while they made a lateral movement. These findings provide support for the idea that we tend to approach positive and avoid negative situations.  相似文献   

7.
8.
The need to accelerate breeding for increased yield potential and better adaptation to drought and other abiotic stresses is an issue of increasing urgency. As the population continues to grow rapidly, the pressure on resources (mainly untouched land and water) is also increasing, and potential climate change poses further challenges. We discuss ways to improve the efficiency of crop breeding through a better physiological understanding by both conventional and molecular methods. Thus the review highlights the physiological basis of crop yield and its response to stresses, with special emphasis on drought. This is not just because physiology forms the basis of proper phenotyping, one of the pillars of breeding, but because a full understanding of physiology is also needed, for example, to design the traits targeted by molecular breeding approaches such as marker-assisted selection (MAS) or plant transformation or the way these traits are evaluated. Most of the information in this review deals with cereals, since they include the world's main crops, however, examples from other crops are also included. Topics covered by the review include the conceptual framework for identifying secondary traits associated with yield potential and stress adaptation, and how to measure these secondary traits in practice. The second part of the review deals with the real role of molecular breeding for complex traits from a physiological perspective. This part examines current developments in MAS and quantitative trait loci (QTL) detection as well as plant transformation. Emphasis is placed on the current limitations of these molecular approaches to improving stress adaptation and yield potential. The essay ends by presenting some ideas regarding future avenues for crop breeding given the current and possible future challenges, and on a multidisciplinary approach where physiological knowledge and proper phenotyping play a major role.  相似文献   

9.
There are 19 species in genusMacaca and some of them are living in sympatry (Fooden, 1980). Although inter-specific hybrids are relatively easy to produce under artificial conditions, hybridization does not occur naturally. What is preventing that among the species of genusMacaca? Three rhesus monkeys acquired a discrimination between pictures with rhesus monkeys and without rhesus monkeys. All subjects showed positive transfer of this discrimination to new pictures with rhesus monkeys and without rhesus monkeys. A further test showed that these monkeys could discriminate between pictures of rhesus monkeys and pictures of Japanese monkeys. The results suggest that rhesus monkeys recognize rhesus monkeys as a class, independent of the actual stimuli such as a picture or an individual monkey. The ability to recognize members of their own species and the opportunities for such learning may be an important factor preventing hybridization among the species of genusMacaca.  相似文献   

10.
The activity of basic motivational systems is reflected in emotional responses to arousing stimuli, such as natural pictures. The manipulation of picture properties such as size or detail allows for investigation into the extent to which separate emotional reactions are similarly modulated by perceptual changes, or, rather, may subserve different functions. Pursuing this line of research, the present study examined the effects of two types of perceptual degradation, namely picture size reduction and blurring, on emotional responses. Both manipulations reduced picture relevance and dampened affective modulation of skin conductance, possibly because of a reduced action preparation in response to degraded or remote pictures. However, the affective modulation of the startle reflex did not vary with picture degradation, suggesting that the identification of these degraded affective cues activated the neural circuits mediating appetitive or defensive motivation.  相似文献   

11.
Native Americans have long relied on the oral transmission of their ideas rather than developing an alphabet and a reliance on written records. While the use of pictures to communicate basic concepts is found throughout Alaska during the historic contact period, the development of an alphabet or pictorial text among Natives in Alaska is extremely limited with examples found only in the Kuskokwim Delta (ca. 1901) and Seward Peninsula (ca. 1914). The later appearance of a pictorial text on Nunivak Island (ca. 1940) is believed to have derived from the Seward Peninsula style. Each of these texts is believed to have originated from the influence of missionaries. This paper traces the appearance and development of a picture text among the Nuniwarmiut Eskimo on Nunivak Island and its current status in the Mekoryuk community.  相似文献   

12.
Much of what is known about word recognition in toddlers comes from eyetracking studies. Here we show that the speed and facility with which children recognize words, as revealed in such studies, cannot be attributed to a task-specific, closed-set strategy; rather, children’s gaze to referents of spoken nouns reflects successful search of the lexicon. Toddlers’ spoken word comprehension was examined in the context of pictures that had two possible names (such as a cup of juice which could be called “cup” or “juice”) and pictures that had only one likely name for toddlers (such as “apple”), using a visual world eye-tracking task and a picture-labeling task (n = 77, mean age, 21 months). Toddlers were just as fast and accurate in fixating named pictures with two likely names as pictures with one. If toddlers do name pictures to themselves, the name provides no apparent benefit in word recognition, because there is no cost to understanding an alternative lexical construal of the picture. In toddlers, as in adults, spoken words rapidly evoke their referents.  相似文献   

13.
This article examines constructivist philosophies for learning with an emphasis on student-centered environments in education and the active involvement of students in learning as they relate new understanding to what they already know and refine previous skills in terms of newly acquired proficiencies. Active learning is explored from a constructivist perspective in which students adopt an analytic approach to questioning and problem solving. Through these processes, students extend their current understanding and emerge as independent musicians, actively engaged in their work as singers, players, composers, improvisers, and listeners. This approach is contrasted with student involvement in hands-on activities in which the focus is on the actions needed to fulfill a given task and limited awareness is devoted to the thinking required to complete the work. I examine the implications of this approach for educational practice and call on policymakers to re-envision music education with attention to engaged learning as perceived within constructivist ways of knowing.  相似文献   

14.
Dass CR  Choong PF 《Peptides》2006,27(12):3479-3488
There is a current trend towards evaluation of molecular agents for treatment of a variety of ailments, including cancer. One class of such biomolecules is proteins, and their shortened versions, peptides. Use of peptidic entities has been hindered by poor bioavailability in vivo and the high cost involved in mass-producing these macromolecular drugs. The need for localized delivery is being met with the development of various biophysical means, which include devices and aids, mainly transdermal and invasive implants. In addition, various cell-based delivery modalities, which include the use of spore-forming bacteria and stem cells, are being explored. This review discusses these methods in turn, and examines ways by which these can be enhanced for peptide delivery to tumors.  相似文献   

15.
Although pictures are widely used as stimuli in cognitive experiments with both humans and animals, the question of how subjects interpret pictures receives less attention. Gaining a better understanding of this is especially important when working with avian subjects, as their visual anatomy and processing is different from that of humans, and even differs from one avian species to another. Successful testing for picture recognition in birds has been carried out mainly with pigeons, but no such research has been explicitly performed with ‘brainy’ birds like parrots, despite the fact that these have been the subject of exciting cognitive research. This study tested kea (Nestor notabilis) mountain parrots for picture–object recognition using a procedure which required the transfer of a learned discrimination task between pictures and objects. Kea successfully showed both picture‐to‐object and object‐to‐picture transfer and performed at a comparable level when pictures were displayed on a touch screen or as printed photographs.  相似文献   

16.
Involving our corporeal bodies in interaction can create strong affective experiences. Systems that both can be influenced by and influence users corporeally exhibit a use quality we name an affective loop experience. In an affective loop experience, (i) emotions are seen as processes, constructed in the interaction, starting from everyday bodily, cognitive or social experiences; (ii) the system responds in ways that pull the user into the interaction, touching upon end users'' physical experiences; and (iii) throughout the interaction the user is an active, meaning-making individual choosing how to express themselves—the interpretation responsibility does not lie with the system. We have built several systems that attempt to create affective loop experiences with more or less successful results. For example, eMoto lets users send text messages between mobile phones, but in addition to text, the messages also have colourful and animated shapes in the background chosen through emotion-gestures with a sensor-enabled stylus pen. Affective Diary is a digital diary with which users can scribble their notes, but it also allows for bodily memorabilia to be recorded from body sensors mapping to users'' movement and arousal and placed along a timeline. Users can see patterns in their bodily reactions and relate them to various events going on in their lives.The experiences of building and deploying these systems gave us insights into design requirements for addressing affective loop experiences, such as how to design for turn-taking between user and system, how to create for ‘open’ surfaces in the design that can carry users'' own meaning-making processes, how to combine modalities to create for a ‘unity’ of expression, and the importance of mirroring user experience in familiar ways that touch upon their everyday social and corporeal experiences.But a more important lesson gained from deploying the systems is how emotion processes are co-constructed and experienced inseparable from all other aspects of everyday life. Emotion processes are part of our social ways of being in the world; they dye our dreams, hopes and bodily experiences of the world. If we aim to design for affective interaction experiences, we need to place them into this larger picture.  相似文献   

17.
How pictures and words are stored and processed in the human brain constitute a long-standing question in cognitive psychology. Behavioral studies have yielded a large amount of data addressing this issue. Generally speaking, these data show that there are some interactions between the semantic processing of pictures and words. However, behavioral methods can provide only limited insight into certain findings. Fortunately, Event-Related Potential (ERP) provides on-line cues about the temporal nature of cognitive processes and contributes to the exploration of their neural substrates. ERPs have been used in order to better understand semantic processing of words and pictures. The main objective of this article is to offer an overview of the electrophysiologic bases of semantic processing of words and pictures. Studies presented in this article showed that the processing of words is associated with an N 400 component, whereas pictures elicited both N 300 and N 400 components. Topographical analysis of the N 400 distribution over the scalp is compatible with the idea that both image-mediated concrete words and pictures access an amodal semantic system. However, given the distinctive N 300 patterns, observed only during picture processing, it appears that picture and word processing rely upon distinct neuronal networks, even if they end up activating more or less similar semantic representations.  相似文献   

18.
We review models of the Baldwin effect, i.e., the hypothesis that adaptive learning (i.e., learning to improve fitness) accelerates genetic evolution of the phenotype. Numerous theoretical studies scrutinized the hypothesis that a non-evolving ability of adaptive learning accelerates evolution of genetically determined behavior. However, their results are conflicting in that some studies predict an accelerating effect of learning on evolution, whereas others show a decelerating effect. We begin by describing the arguments underlying the hypothesis on the Baldwin effect and identify the core argument: adaptive learning influences the rate of evolution because it changes relative fitness of phenotypes. Then we analyze the theoretical studies of the Baldwin effect with respect to their model of adaptive learning and discuss how their contrasting results can be explained from differences in (1) the ways in which the effect of adaptive learning on the phenotype is modeled, (2) the assumptions underlying the function used to quantify fitness and (3) the time scale at which the evolutionary rate is measured. We finish by reviewing the specific assumptions used by the theoretical studies of the Baldwin effect and discuss the evolutionary implications for cases where these assumptions do not hold.  相似文献   

19.
To address the pressing problems associated with biodiversity loss, changes in awareness and behaviour are required from decision makers in all sectors. Science-policy interfaces (SPIs) have the potential to play an important role, and to achieve this effectively, there is a need to understand better the ways in which existing SPIs strive for effective communication, learning and behavioural change. Using a series of test cases across the world, we assess a range of features influencing the effectiveness of SPIs through communication and argumentation processes, engagement of actors and other aspects that contribute to potential success. Our results demonstrate the importance of dynamic and iterative processes of interaction to support effective SPI work. We stress the importance of seeing SPIs as dynamic learning environments and we provide recommendations for how they can enhance success in meeting their targeted outcomes. In particular, we recommend building long-term trust, creating learning environments, fostering participation and ownership of the process and building capacity to combat silo thinking. Processes to enable these changes may include, for example, inviting and integrating feedback, extended peer review and attention to contextualising knowledge for different audiences, and time and sustained effort dedicated to trust-building and developing common languages. However there are no ‘one size fits all’ solutions, and methods must be adapted to context and participants. Creating and maintaining effective dynamic learning environments will both require and encourage changes in institutional and individual behaviours: a challenging agenda, but one with potential for positive feedbacks to maintain momentum.  相似文献   

20.
Scientists need to find innovative ways to communicate their findings with restoration practitioners in an era of global change. Apps are a promising bridge between restoration science and practice because they apply broad scientific concepts to specific situations. For example, habitat connectivity promotes ecological function, but practitioners lack ways to incorporate connectivity into decision‐making. We created an app where users calculate how habitat restoration or loss affects connectivity. By providing our app as an example and discussing the benefits and challenges in creating apps for practitioners, we encourage other restoration ecologists to similarly create apps that bridge science with practice.  相似文献   

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