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1.
The Draw-an-Archaeologist Test (DART) is an easy way to elieit students' conceptions about archaeology and can be adapted to other subject matter. When implemented as the first activity of an archaeology unit, it provides a starting point for introducing archaeology and addressing students' misconceptions about it. In this drawing activity, students are asked to describe not only what archaeologists do, but who they are in terms of gender and ethnicities. This activity can be used to generate a discussion on equity and to access differences between genders and ethnicities, which fulfills one of the national science education standards for the history and nature of science.  相似文献   

2.
Allen JF 《Current biology : CB》2005,15(22):R929-R932
Recent work identifies two kinases required for phosphorylation of proteins of chloroplast thylakoid membranes. One kinase, STN7, is required for phosphorylation of light-harvesting complex II; another, STN8, is required for phosphorylation of photosystem II. How do these kinases interact, what do they do, and what are they for?  相似文献   

3.
In the phytoplankton of the western North Atlantic, speciesare considered adapted to impoverished nutrient availabilityif they respond best to such conditions, and are consideredunadapted only if they do not respond. The same holds for improvednutrient availability. Further, if species adapted to impoverishednutrient availability are broader niched, then narrower nichedspecies are adapted only to improved nutrient availability.Thus two kinds of species are described: (i) adapted-to-impoverished-nutrient,broader niched species; (ii) adapted-to-improved-nutrient, narrowerniched species.  相似文献   

4.
To understand how our brain evolved and what it is for, we are in urgent need of knowledge about the cognitive skills of a large variety of animal species and individuals, and their relationships to rapidly disappearing social and ecological conditions. But how do we obtain this knowledge? Studying cognition in the wild is a challenge. Field researchers (and their study subjects) face many factors that can easily interfere with their variables of interest. Although field studies of cognition present unique challenges, they are still invaluable for understanding the evolutionary drivers of cognition. In this review, I discuss the advantages and urgency of field‐based studies on animal cognition and introduce a novel observational approach for field research that is guided by three questions: (a) what do animals fail to find?, (b) what do they not do?, and (c) what do they only do when certain conditions are met? My goal is to provide guidance to future field researchers examining primate cognition.  相似文献   

5.
Recent experimental work on human control of complex systems has drawn attention to the discrepancy that may exist between the person's reported knowledge of the system and their ability to control it. Sometimes people act correctly but cannot answer questions about what they are doing; sometimes they can say verbally what they should do (perhaps having had verbal instruction in the right answers), but still do not do it. This discrepancy is of major practical importance, for example in designing training programmes or in eliciting expert knowledge for incorporation in a mechanical 'expert system'. It is also puzzling for psychological theory, as it rules out certain plausible models of the functioning of the brain. This paper considers what mechanisms are still possible.  相似文献   

6.
A traditional view of cognition is that it involves an internal process that represents, tracks or predicts an external process. This is not a general characteristic of all complex neural processing or feedback control, but rather implies specific forms of processing giving rise to specific behavioural capabilities. In this paper, I will review the evidence for such capabilities in insect navigation and learning. Do insects know where they are, or do they only know what to do? Do they learn what stimuli mean, or do they only learn how to behave?  相似文献   

7.
A traditional view of cognition is that it involves an internal process that represents, tracks or predicts an external process. This is not a general characteristic of all complex neural processing or feedback control, but rather implies specific forms of processing giving rise to specific behavioural capabilities. In this paper, I will review the evidence for such capabilities in insect navigation and learning. Do insects know where they are, or do they only know what to do? Do they learn what stimuli mean, or do they only learn how to behave?  相似文献   

8.
The resurrection plant, Haberlea rhodopensis can survive nearly total desiccation only in its usual low irradiation environment. However, populations with similar capacity to recover were discovered recently in several sunny habitats. To reveal what kind of morphological, structural and thylakoid-level alterations play a role in the acclimation of this low-light adapted species to high-light environment and how do they contribute to the desiccation tolerance mechanisms, the structure of the photosynthetic apparatus, the most sensitive component of the chlorophyll-retaining resurrection plants, was analyzed by transmission electron microscopy, steady state low-temperature fluorescence and two-dimensional Blue-Native/SDS PAGE under desiccation and rehydration.  相似文献   

9.
Neurofilaments: abundant but mysterious neuronal structures   总被引:1,自引:0,他引:1  
Neurofilaments are by far the most obvious elements of the neuronal cytoskeleton. Their subunits are biochemically among the most abundant neuron specific components, particularly in axons. Clearly they must be important to the neuron or they would not be so numerous But what do they do?.  相似文献   

10.
People not always do what they say that they do, nor do they always say what they really do, an opaqueness that seems to be a necessary condition for the production and reproduction of their mutual relations in society. This lesson about the discrepancy between people’s words and their deeds, between verbally expressing social norms for the well-being of everybody while simultaneously striving for individual or group interests, was already taught by Malinowski (Argonauts of the western Pacific: an account of native enterprise and adventure in the archipelagoes of Melanesian New Guinea. Routledge, London, 1922). He may have learned it himself during his own lengthy fieldwork in New Guinea, but it may also have been an anthropological operationalization of the dictum of Freud, with whom Malinowski was struggling intellectually (at least from his side), that people are not always conscious of the motives of their own words and behavior. It also happens, however, that politicians, business, and church people alike consciously create stories or myths in which they hide their own personal our group intentions. These stories or myths are not only works of art of the human mind, but when they are successfully told within the context of, or directly concern power relationships, the narrator may be attributed mana. At least, this is what many Polynesians would do. In this paper, I will give several ethnographic examples from Polynesia, where I have been working for the last 28 years, in order to defend my theoretical stance concerning asymmetrical ideology and power.  相似文献   

11.
《Biochemical education》1999,27(2):93-96
We have successfully implemented a simple computerised data acquisition system which has been used extensively in our biochemistry teaching laboratory classes. Our experience suggests that it is important to consider carefully what the computers are required to do in the laboratory well before their introduction. Finally, we believe that it is desirable to keep the system simple and sufficiently versatile that it can be adapted to several different uses without too much difficulty.  相似文献   

12.
What is a support vector machine?   总被引:3,自引:0,他引:3  
Noble WS 《Nature biotechnology》2006,24(12):1565-1567
Support vector machines (SVMs) are becoming popular in a wide variety of biological applications. But, what exactly are SVMs and how do they work? And what are their most promising applications in the life sciences?  相似文献   

13.
Ultimate divers     
An extraordinary variety of mammals, birds, amphibians and reptiles are adapted to life in the oceans. Many of them spend their entire lives there without being able to breathe underwater. But just how do they exploit this hostile environment?  相似文献   

14.
Decision trees have been applied to problems such as assigning protein function and predicting splice sites. How do these classifiers work, what types of problems can they solve and what are their advantages over alternatives?  相似文献   

15.
Abstract There is a world-wide research effort to develop biodegradable polymers as a waste-management option for polymers in the environment. This effort may prove to be fruitless unless we can agree on a definition and test protocols—what do we expect biodegradable polymers to do in the environment and how do we demonstrate that they do what we expect? Establishing a definition and test protocols is not trivial; the task is made complex by the wide range of disciplines involved directly in or interested in the subject, including polymer scientist, biochemists, environmentalists, legislators, and laypeople, all with their own perspectives and expectations. In this paper, I present arguments in favor of biodegradable polymers and indicate what remains to be done to satisfy detractors that they represent a viable option for polymer waste-management.  相似文献   

16.
There are more senior house officers than doctors in any other training grade in Britain but nobody knows what they do in hospitals or has a clear idea what skills they should be learning. Nobody is responsible for them and they suffer from having a poor career structure and inadequate training. Now that there are government initiatives to reduce the hours that junior doctors work and to limit the time it takes to train to become a specialist, the problems that senior house officers face can no longer be ignored. A conference for senior house officers held last week talked about the problems that they face and tried to find some solutions.  相似文献   

17.
Secretion of proteins into host cells by Apicomplexan parasites   总被引:1,自引:0,他引:1  
The phylum Apicomplexa consists of a diverse group of obligate, intracellular parasites. The distinct evolutionary pressures on these protozoans as they have adapted to their respective niches have resulted in a variety of methods that they use to interact with and modify their hosts. One of these is the secretion and trafficking of parasite proteins into the host cell. We review this process for Theileria , Toxoplasma and Plasmodium . We also present what is known about the mechanisms by which parasite proteins are exported into the host cell, as well as information on their known and putative functions once they have reached their final destination.  相似文献   

18.
Although ignorance and uncertainty are usually unwelcome feelings, they have unintuitive advantages for both human and non-human animals, which we review here. We begin with the perils of too much information: expertise and knowledge can come with illusions (and delusions) of knowing. We then describe how withholding information can counteract these perils: providing people with less information enables them to judge more precisely what they know and do not know, which in turn enhances long-term memory. Data are presented from a new experiment that illustrates how knowing what we do not know can result in helpful choices and enhanced learning. We conclude by showing that ignorance can be a virtue, as long as it is recognized and rectified.  相似文献   

19.
Two of the most fundamental questions in tadpole biology, also applicable to most small, under-studied organisms are: (1) ‘Why are they built the way they are?’ and (2) ‘Why do they live where they do?’ Regrettably, despite significant progress in most aspects of tadpole biology, the answers to these questions are not much better now than they were in the last century. We propose that an autecological approach, that is the careful observation of individuals and how they interact with the environment, is a potential path towards a fuller understanding of tadpole ecomorphology and evolution. We also discuss why more attention should be given to studying atypical tadpoles from atypical environments, such as torrential streams, water-filled cavities of terrestrial plants and wet rock surfaces neighbouring streams. Granted, tadpoles are rare in these settings, but in those unusual habitats the physical environments can be well described and characterized. In contrast, the more common ponds where tadpoles are found are typically too structurally complex to be easily delineated. This makes it difficult to know exactly what individual tadpoles are doing and what environmental parameters they are responding to. Our overall thesis is that to understand tadpoles we must see exactly what they are doing, where they are doing it, and how they are doing it. This takes work, but we suggest it is feasible and could greatly advance our understanding of how anuran larvae have evolved. The same strategies for studying tadpoles that we encourage here can be applied to the study of many other small and fast-moving animals.  相似文献   

20.
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