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Fabricando mundos. Realidad, simulacro e inmanencia [Manufacturing worlds. Reality, simulacra and im
Digital manufacturing in both as art and technology is a new way of designing, re-creation and re-invention of reality. This paper considers, from an epistemological point of view, the process of digital fabrication and its hyperlinks to known and simulated reality, and its ontological nature. Through documentation and methodological approach to the construction of a Moebius strip, this paper analyzes the nature and specifications of digital manufacturing. For this purpose, it makes a study of s
Author(s): Amen, Fernando Garc?a; ?lvarez, Marcelo Payss?; Bo

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Introduction

A number of biological changes may occur as a result of eutrophication. Some of these are direct (e.g. stimulation of algal growth in water bodies), while others are indirect (e.g. changes in fish community composition due to reduced oxygen concentrations). This section summarizes some of the typical changes observed in aquatic, marine and terrestrial ecosystems following eutrophication.

Some typical changes observed in lakes following artificial eutrophication are summarized in Table 2
Author(s): The Open University

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1.6 Obesity treatment

Obesity treatment is only successful if weight is reduced and maintained to within a desired range. There are three approaches to obesity treatment: changing behaviour and diet is the most common approach although drugs and surgery can be used in some severe cases of obesity.

Behaviour and diet: it is important to be realistic about an obese patient's target weight as many patients have over-ambitious targets that they are unlikely to achieve. A severely obese patient probably ca
Author(s): The Open University

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1.1 Water as a resource

Water is arguably the most important physical resource as it is the only one that is essential for human survival; we would die very quickly without it. Other physical resources can make life more comfortable, but water makes life possible. If you were shipwrecked on an island, a priority would be to find a source of fresh water fairly quickly; the thought of looking for other physical resources on the island, such as minerals for construction, fuel for warmth or metals for tools would come m
Author(s): The Open University

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Introduction

Most of us are probably more familiar with the Earth’s physical resources than we realise. They are basically those non-biological parts of our natural world that we can put to good use. In this unit we will help you to appreciate aspects of one particular physical resource - water use and the w
Author(s): The Open University

6 Concentrating, storing and transporting energy

The Earth is awash with energy from sources other than fossil fuels; thousands of times as much a
Author(s): The Open University

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7.1 The spectra of galaxies

  • The spectrum of a galaxy is the composite spectrum of the objects of which it is composed.

  • The optical spectrum of a normal galaxy contains contributions from stars and HII regions. An elliptical galaxy has no HII regions and has an optical spectrum that looks somewhat like a stellar spectrum but with rather fainter absorption lines. A spiral galaxy has both stars and star-forming regions, and its optical spectrum is the composite of its st
    Author(s): The Open University

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4.6 Accretion power

Calculations based on the above accretion disc hypothesis show that if a mass m falls into the black hole, then the amount of energy it can radiate before it finally disappears is about 0.1 mc2, or about 10% of its rest energy. Other than matter-antimatter annihilation, this is the most efficient process for converting mass into energy ever conceived. A comparable figure for the nuclear fusion of hydrogen in stars is only 0.7% of the rest energy of the four hydrogen n
Author(s): The Open University

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7 Final thoughts

We deliberately chose a wide range of different initiatives to explore, to reflect the broad range of initiatives underway. And yet, as you have seen, there are common threads that run though all our examples, such as the representativeness of ‘public’ opinion and how outcomes input into policy making. A key issue that Reading 5 highlighted was
Author(s): The Open University

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3.6 How valuable have consensus conferences proved to be?

From the two case studies just considered, certain factors seem critical for the success of lay input into decision making. First, both the choice of topic of the conference and its presentation is crucial. If the plant biotechnology conference had been billed as ‘genetic modification’ (as opposed to plant biotechnology), it might have had more resonance with the political and popular perceptions and hence had greater impact. Independence of the lay or citizens' panel is another key point
Author(s): The Open University

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4.1 Introduction

As bacteria secrete such powerful chelators into the environment, iron in other organisms must be kept under very close control. Any free iron within an organism is likely to be chelated by a siderophore, which may lead to bacterial infection within the organism In this Section we shall examine the biochemical systems that handle iron within the human body. The two areas we shall study are iron transport and iron storage.


Author(s): The Open University

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4.4 Hormonal control of sperm production

The most important hormone involved in controlling sperm production is a steroid called testosterone. This is produced in the testis itself, by the Leydig cells (see Figure 12a). The testosterone is released from the Leydig cells between the tubules, and taken up by the neighbouring Sertoli cells. The Leydig cells are stimulated to make testosterone by two other hormones, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are both produced by the pituitary gland and
Author(s): The Open University

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1 What is development?

In this unit we begin to look at the human being in the context of an individual life cycle, examining some of the processes that contribute to the formation of a new person. This is the first time that many of you will have encountered this level of biological detail; we would ask that you take the time to understand it fully at this stage. We hope to show you that, far from being a dry academic subject, the study of biology allows us to glimpse a dimension of dynamic sophistication and eleg
Author(s): The Open University

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Learning outcomes

By the end of this unit you should be able to:

  • explain the principles that underlie the ability of wave power to deliver useable energy;

  • outline the technologies that are used to harness the power of waves;

  • discuss the positive and negative aspects of wave energy in relation to natural and human aspects of the environment.


Author(s): The Open University

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1 Wind energy

Wind energy was the fastest growing power source at the start of the 21st century, yet wind-driven mills and pumps, and nautical sails for transport were, along with waterwheels, the first mechanical devices to power industrial production. The advantages of harnessing wind energy are obvious; it is free, clean and widely available (but see later). Although a favoured source of ‘green’ energy, the increasing deployment of wind turbines where they are most efficient, on hilltops and coasts,
Author(s): The Open University

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6 Summary

Solar power is an immense source of directly useable energy and ultimately creates other energy resources: biomass, wind, hydropower and wave energy.

Most of the Earth's surface receives sufficient solar energy to permit low-grade heating of water and buildings, although there are large variations with latitude and season. At low latitudes, simple mirror devices can concentrate solar energy sufficiently for cooking and even for driving steam turbines.

The energy of light shifts el
Author(s): The Open University

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2 Solar thermal energy

Solar heating of trapped air, water and solids has been used for centuries, but modern architectural design can enhance all three effects for space heating, hot water supply and heat storage. Such passive solar heating relies on short-wave radiation being absorbed by materials so that they heat up and then slowly re-emit long-wave radiation. The most obvious example is inside a greenhouse, where solar radiation that passes through the glass heats the inside air to temperatures well abo
Author(s): The Open University

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1.7.1 Carboniferous mires

During the late Carboniferous, mires developed over vast areas of the UK. Much of today's land area was an extensive, low-lying plain bordering a sea to the south (a sea that was soon to be the site of a mountain-building episode). Any mountains that existed lay hundreds of kilometres to the north. Large river systems meandered southwards across these plains.

At that time, the UK lay in tropical latitudes, almost on the Equator (see Author(s): The Open University

Learning outcomes

By the end of this unit you should be able to:

  • define and use each of the terms printed in bold in the text;

  • describe the different levels of protein structure and their interdependence;

  • explain how steric limitations determine secondary structure in polypeptides;

  • describe, using examples, the relationship between protein structure and function;

  • understand the significance of domains in protein function and how t
    Author(s): The Open University

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