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Sneller klaar bundel : Allerlei opdrachten
alfabet.jpg

Kinderen van het eerste leerjaar die sneller klaar zijn, kunnen zelfstandig in deze bundel werken. Er komen heel wat rekenoefeningen aan bod zoals optellen, splitsen, aftrekken, de tafel van 2 en deze van 10. Dit afgewisseld met …


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Fall 2012 Capstone Presentation - Introduction
On December 13th, students from the Fall Capstone class presented their projects. Taught this semester by Prof. Gavin Shatkin, the Capstone is a required course that all Master's students in the LPP and MURP programs take in their final semester. This semester's students worked with Street-Works and the City of Quincy on a plan for the redevelopment of the Quincy Center MBTA Station.
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World Science Festival 2008: Beyond Einstein, Part 7 of 8
Albert Einstein spent his last thirty years unsuccessfully searching for
a 'unified theory' - a single master principle to describe everything
in the universe, from tiny subatomic particles to immense clusters of
galaxies. In the decades since, generations of researchers have
continued working toward Einstein's dream.

Renowned physicists Leonard Susskind, Jana Levin, Jim Gates, and prominent historian Peter Galison discussed what's been achieved and tackle

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Integrative Biology 131 - Lecture 02: Skeletal System

General Human Anatomy. UC Berkeley lecture with Professor Marian Diamond. The functional anatomy of the human body as revealed by gross and microscopic examination.

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Carolling at Memorial Church
Each year in December, Harvard's Memorial Church presents members of the University community and beyond with the gift of song. For more than a century, the church's Harvard University Choir has performed two Christmas carol services that include readings by the clergy, and a mix of traditional and contemporary carols and hymns sung by both the choir and congregation. Read more in the Harvard Gazette: http://news.harvard.edu/gazette/story/2012/12/a-musical-gift/
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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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4.4 Reducing nutrient availability

Once nutrients are in an ecosystem, it is usually much harder and more expensive to remove them than tackle the eutrophication at source. The main methods available are:

  • precipitation (e.g. treatment with a solution of aluminium or ferrous salt to precipitate phosphates);

  • removal of nutrient-enriched sediments, for example by mud pumping; and

  • removal of biomass (e.g. harvesting of common reed) and using it for thatchi
    Author(s): The Open University

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1.3 Balanced energy intake

There is a need for a certain daily energy intake to allow metabolism to occur in the body. Metabolism means all the chemical reactions occurring in the body and there are two types of process involved: catabolism breaks down larger molecules into smaller ones often with energy release and anabolism is the building up of larger molecules from smaller precursors, often requiring energy. The body requires energy to power anabolic, mechanical (for example, muscle contraction
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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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Acknowledgements

The material acknowledged below is contained in Chapter 3 of An Introduction to Galaxies and Cosmology (eds Mark H Jones and Robert J Lambourne), published by the Press Syndicate of The University of Cambridge  in association with The Open University. Copyright © The Open University, 2003, 2004.

This publication forms part of an Open University course S282 Astronomy.


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7.7 Physical hazards

In any laboratory, potential hazards arise from the use of electrical equipment. The legal requirements relating to the use and maintenance of such equipment are contained in the ‘Electricity at Work Regulations 1989’ (EAW). The regulations require certain safety objectives to be achieved but do not prescribe in detail the measures to be taken. Instead, precautions should be selected appropriate to risk depending on particular work activities.

‘Portable’ electrical equipment –
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5.2 Cryogenic liquids and ionising radiation safety

5.2.1 Cryogenic liquids

There are a number of hazards associated with cryogenic liquids, the main one being that when accidentally released the liquid expands hugely to form a gas (600 times in the case of nitrogen). The formation of such a large volume of gas can lead to asphyxiation in confined areas.

The other main hazard is cold burns (frostbite).

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5 Summary

At the time of writing (2006) a relatively small number of types of GM crop have been grown globally, in a limited number of countries. The take-up of these crops has been relatively high in countries like the USA and Canada, but very much lower in Europe. However, there is a very rapid increase in the growth of GM crops in developing countries.

The technique most commonly used to introduce new genetic material into dicots has involved the use of a modified soil bacterium, Agrobacter
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4.1 Vitamin A deficiency

Vitamin A, more properly known as retinol, is an important chemical intermediate in a number of biochemical processes in mammals. It is involved in vision, and is found in the rod cells of the retina of the eye. These cells are particularly important in seeing at low light levels, and night blindness is a symptom of vitamin A deficiency (VAD). Vitamin A is also involved in the proper functioning of the immune system. Children suffering from VAD are prone to serious infections, and often die f
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1 How do organisms acquire iron?

Metals are an essential part of biological chemistry. Of all the trace elements, iron is the most important, especially as it is present in many essential enzymes and proteins. But how do organisms acquire the iron from their surroundings? Clearly, organisms need to absorb iron biochemically before it can be used in proteins. Also, some method of replacing lost iron quickly is needed: for instance, how is blood replaced once it has been lost through a cut? This prompts the question: what bioc
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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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