3.5.3 Mechano-electrical transduction is rapid

Many other sensory receptors, such as photoreceptors and olfactory neurons, employ second messengers in the transduction process. This is not true for hair cells. The rapidity with which they respond makes this impossible. In order to deal with the frequencies of biologically relevant stimuli, transduction must be rapid. The highest frequency humans can hear is about 20 000 Hz. This in effect means that hair cells must be able to turn current on and off 20 000 times per second (200 000 tim
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After studying this course, you should be able to:

  • understand the debates and issues surrounding evolution and religion.


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3.4.2 Ecological changes

Creation of a reservoir produces ecological changes not only to the area of the reservoir itself, by destroying the natural vegetation, but also upstream and downstream of the reservoir. The gradient of a river upstream of a reservoir may be reduced, so the water will slow down, changing the character of the river, causing deposition of sediment, and changes to the natural vegetation and animal life. Downstream of the reservoir the discharge will change, as well as the sediment load, also aff
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Former Singaporean PM's health deteriorates further
The health of former Singapore Prime Minister Lee Kuan Yew weakens further as his son and current Prime Minister Lee Hsien Loong visits him in hospital. Julie Noce reports. Subscribe: http://smarturl.it/reuterssubscribe More updates and breaking news: http://smarturl.it/BreakingNews Reuters tells the world's stories like no one else. As the largest international multimedia news provider, Reuters provides coverage around the globe and across topics including business, financial, national, and i
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"Ecology, Human Rights, and Large Dam Projects in South Asia"
Kathleen Morrison is Professor, Department of Anthropology; Director, Center for International Studies, The University of Chicago. There is little doubt that climate change, deforestation, erosion, and the unequal distribution of natural resources around the globe are of pressing importance everywhere, but these problems are perhaps most acute in Asia, home to 64 percent of the world’s population. Much of this population (1 and 1.3 billion, respectively) is concentrated in India and China, tw
Author(s): The Center for International Studies at the Univer

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Environmental Regulation of Federal Lands and Activities: Uncle Sam as a Regulated Entity
Ray Swenson examines the environmental impacts of federal land use policy.
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The Arts in Every Classroom: What is Art?
The Learner Teams and students explore the nature of theatre, music, dance, and visual art as they consider their own definitions for each art form. They watch an excerpt from Quidam, a surrealistic performance piece that combines the four art forms in unusual ways, and begin to explore connections between fantasy and reality.
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Exodus Chapter 1 - New International Version of the Bible
This video contains a high quality narration of The Book of Exodus, Chapter 1, from the New International Version of the Bible.  Scriptures read by professional voice actors, along with good music and sound effects.  No moving images.
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Environment: LA River
Who killed the river that runs through Los Angeles? Did you even know there was a river? Using a mix of archive and new footage , this album tells the fascinating story of a city that has ignored the benefits of its river for decades. Now waking up to the fact that it could be a green belt with more acreage than all of Central Park, river activists are fighting developers to bring back nature to central Los Angeles. Up till now the city conquered the threat of floods by concreting over the river
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Except for third party materials and otherwise stated (see http://www.open.ac.uk/conditions terms and conditions), this content is made available under a http://creativecommons.org/licenses/by-nc-sa/2

Radio-quiet AGNs

There has been a great deal of debate about whether there really are two different types of Seyfert or whether they can both be accounted for by the same model.

For example, suppose that you look at the model AGN in Figure 36a from a direction not too far from the rotation axis of the torus. You will see
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1.8 Enter aspirin!

Aspirin is able to release part of its ester group (Figure 15) in a hydrolysis reaction. Look again at the structure of aspirin, 2.8, and identify this group on the molecule. It is known as an acetyl group and accounts for aspirin also being called acetylsalicylic acid. The acetyl group on aspirin is fairly easily removed and can be available for forming another ester with an —OH group on another molecule; in this case, part of the structure that makes up the inside of the cavi
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Learning outcomes

After studying this course, you should be able to:

  • convert between wavelengths and frequencies

  • describe the main differences between lasers and LEDs as used as light sources for optical-fibre communications systems

  • describe the difference between direct and external modulation of a laser

  • describe the difference in structure and performance of step-index multimode, graded-index multimode and single-mode optical fibres

  • dr
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7.3 The eukaryotic chromosome

Whilst the bulk of eukaryotic DNA is packaged by proteins different from those in the eubacterial chromosome, the principles of bending DNA and neutralising the negative charges in its backbone are shared. Eukaryotic cells have considerably larger genomes than do prokaryotes (in most cases over 1000 times the size of the E. coli genome – see Author(s): The Open University

8.2 Chromosome scaffolds

Most of the chromosomal DNA chains within the interphase nucleus are believed to be held on a scaffold or backbone structure made from various proteins, with loops of between 20 and 200 kb extruding from attachment sites. This chromosome structure is shown schematically in Figure 40. The scaffold, as well as permitting further compaction, serves to bring the DNA together in organised regions. There are many different protein components of these scaffolds, amongst them DNA topoisomerases.


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Indigenous Peoples' Legal Water Forum 2009 Session 9
A forum to explore the rights of Indigenous peoples to be involved in the governance of freshwater. Law Professor Lee Godden and Director of the Centre for Resources, Energy and Environmental law, University of Melbourne, Australia, "Indigenous Property Rights to Water: Environmental Flows, Cultural Values and Tradeable Property Rights in Australia".
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Learning outcomes

After studying this course, you should be able to:

  • understand the legal framework of the Health and Safety at Work etc. Act 1974 and Regulations associated with it

  • understand the employers’, employees’ and visitors’ duties

  • evaluate hazards and risks in order to carry out a risk assessment

  • understand the legal requirement to report any accident or dangerous occurrence

  • develop risk assessments for scientific laborat
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Efficient Computer-User Interface in Electronic Mail Systems
This research explores the question of improving user- computer interface. The approach is one of observing and codifying various parameters that influence the efficiency of interface in the context of electronic mail tasks. In the paper the authors observe 'expert' and 'regular' users of a mail system and analyze the sources of efficiency. It is clear that experts use a different, more specialized, set of commands in performing standard mail tasks. While experts perform these tasks with fewer e
Author(s): Akin, Omer

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What is a Blizzard?
This term gets tossed around at least once every winter for the big snowstorm of the season, and most of the time - it's WRONG!  Blizzards have a very specific, difficult set of criteria to meet before they can be categorized as this type of winter storm - and it has more to do with wind and visibility than snow. (01:55)
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Cogs v2
Cogs v2 - John Savage Keywords:UNSPECIFIED
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After studying this course you should be able to:

  • understand what writing an assignment involves;
  • identify their strength and weaknesses;
  • consider the functions of essays and reports;
  • develop writing skills, whatever the stage they have reached.

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