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Research Help-Attach Notes to Any File or Website in Windows
Want to remind yourself of that super important task each time you open a certain website? Veronica explores GumNotes, which can attach a reminder to any file or website. (01:36)
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Sing, Sing, Sing
Performed by the University of Richmond Jazz Ensemble at the 2012 Cuban Spectacular. Featuring dancers Myra Daleng and Michael Whitten, Emma Phillips, '13, on drums, and Nick Yeutter, '15 on clarinet. Directed by Dr. Mike Davison.
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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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2.4 Analysis of nucleic acids by electrophoresis and hybridisation

Nucleic acids can be separated according to size by gel electrophoresis, most commonly performed using a horizontal gel (Figure 7a). This is in contrast to the vertical gel electrophoresis set-up, which is generally used for analysis of proteins.

The size of DNA molecules is usually expressed in terms of the number of
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1.5 Obesity

At the time of writing (2004) 20% of the adult population of the UK is classified as obese. The number of obese children has doubled since 1982, 10% of six year olds and 17% of fifteen year olds are now classified as obese. As shown in Table 4, obesity is recognized when the BMI exceeds 30 and occurs quite simply wh
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4 Fossil fuels

Part of the incoming solar energy becomes stored in fossil fuels (oil, gas and coal:
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3.6 A ‘non-active’ class – the starburst galaxies

We end this section by drawing a distinction between the classes of active galaxy that are described in the previous subsections and the starburst galaxies mentioned earlier. As you have seen, starburst galaxies are essentially ordinary galaxies in which a massive burst of star formation has taken place. Their spectra show emission lines from their many HII regions and infrared emission from dust but, in the main, they do not show unusual activity in their nuclei. In the past they were
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3.2 Public consultation vs public engagement

‘Public consultation’ is not a new concept in policy making. For society to function effectively, laws and policies must have public support. It is desirable, therefore, to have some idea of what the public thinks about an issue before regulation is finalised. Consultation is based on establishing the nature of a socially collective view that we call ‘public opinion’. The main means of establishing public opinion with at least some degree of confidence is the opinion poll, the methodo
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3.1 Introduction

On an autumnal morning in November 1994, a group of people gathered at Regent's College, London, conscious that they were making history. The purpose of the meeting was to discuss an important issue: plant biotechnology and how it should be regulated in the UK. At the time, the genetic engineering of plants was emerging as a technology of great potential for the development of new pest-resistant, higher yield crops, although the technique hadn't attracted the degree of media attention and pub
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3.5 A new life

There is a common belief that life begins at the moment of conception, i.e. when a sperm fuses with an egg. This is a step forward from past years, when life was alleged to start at the time of ‘quickening’, i.e. when a woman could feel her fetus moving inside her. However, both these opinions suffer from an underlying falsehood: that life ‘begins’ at all. Life is a continuum; gametes are produced by living parents, and fuse to produce new living individuals, but unfused gametes are n
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4.3 Gamete production in men

A sexually mature man is producing sperm all the time at a rate of around 300–600 per gram of testis per second. This provides the 500 million or so which are released at each ejaculation. But the formation of an individual sperm takes about nine weeks (64 days). Sperm are produced in the testes, and production is most efficient at a temperature several degrees lower than the normal body temperature of 371°C. For this reason the testes (plural of testis) are suspended outside the body cavi
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8 Summary

  1. The rate at which water infiltrates into the ground depends on the permeability of the rocks and the state of the ground surface. Below the ground surface there is an unsaturated zone which has air in the pore spaces, and a saturated zone which has all the pores filled with water. The water table is the boundary between the unsaturated zone and the saturated zone, and is the level at which water stands in wells. Water below the water table is called groundwa
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6 Permeability

It is important to distinguish clearly between porosity and permeability. Porosity is a measure of how much water can be stored in a rock, whereas permeability is a measure of the properties of a rock which determine how easily water and other fluids can flow through it (see Section 4). Permeability depends on the exte
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1 Water underground

Many people have the impression that underground water occupies vast caverns, such as those in the Derbyshire Peak District, flowing from one cavern to another along underground rivers. This is a common misconception: underground caverns are fairly rare, but huge quantities of water exist underground, within rocks. This is because many rocks contain pores, spaces that come in all shapes and sizes. In sediments, and consequently sedimentary rocks, there are often pores between gr
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1 Wave energy

The energy carried by ocean waves derives from a proportion of the wind energy transferred to the ocean surface by frictional drag. So, ultimately it stems from the proportion of incoming solar energy that drives air movement. Just how much energy is carried by a single wave depends on the wind speed and the area of ocean surface that it crosses; wave height, wavelength, and therefore wave energy, are functions of the distance or fetch over which the wind blows. Not surprisingly the ma
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6 Summary

  1. Waterlogged organic matter accumulates in deltaic, coastal barrier or raised mires to form peat. Coal forms by the compaction and decomposition of peat. Chemical changes imposed by increasing temperature and pressure over time determine the coal rank.

  2. Coalfields can be classified as either exposed or concealed, depending on whether or not the coal-bearing rocks are hidden by younger strata. In most coalfields, mining commenced in the shallower
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2.7 Summary

  1. Eukaryotic cells contain numerous distinct types of membrane-bound compartment. Transport vesicles move proteins and other molecules between the compartments.

  2. Proteins contain signalling sequences or patches that specify their destination compartment.

  3. Proteins destined for lysosomes, secretion or the plasma membrane are synthesised in the ER, transported to the cis Golgi, modified in the Golgi apparatus, and sorted and pa
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1.7 Localization of signalling proteins

Since signalling proteins cannot diffuse as rapidly as small second messengers, they need be close to their downstream target in order to be able to function. Where they are located with respect to both their subcellular position and their immediate neighbours is therefore vitally important. The plasma membrane is usually the initial location, and proteins can be attached to the plasma membrane in various ways (Author(s): The Open University

Acknowledgements

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Figures

Figures 3, 5–7, 40, 41 Voet, D. and Voet, J. G. (1995) Biochemistry, 2nd edn, copyright © 1995 John Wiley & Sons Inc

Figures 4, 8, 9a, 10, 14, 24, 25a,c Voet, D. and Voet,
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7.4 Proteomics

Traditionally, the study of the biochemistry or structure of a protein necessitated its purification to a high degree. The development of protocols for cloning, manipulation and expression of genes greatly facilitated this kind of study, as will be clear to you from the previous section. In recent years, a number of high-throughput techniques have, to an extent, obviated traditional approaches and permit simultaneous analysis of all the expressed proteins in a cell or organism, known as the <
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