bluuebunny/crossref_metadata_2025 huggingface dataset:
Endocrinology
Authors: Phylactou Maria
Published: November 2020

Since 1905, when Professor Ernest Starling first used the term ‘hormone’ in one of four Croonian lectures at the Royal College of Physicians, a lot has changed in the world of endocrinology. Endocrinology is the study of hormones and subsequent pathologies that arise from their imbalance. Endocrinology is also a specialty of common sense where application of basic physiological principles, such as negative feedback loops, can help any doctor appropriately interpret blood test results and form a management plan. Diabetes forms a large part of the specialty and is becoming one of the most prevalent conditions of our time. A solid understanding of its diagnosis, management, and complications is a paramount skill that every doctor should possess in this day and age. New developments in the management of type 1 diabetes with insulin pumps and new drug-targeted treatments of obesity and the metabolic syndrome make this an exciting and ever changing field. But diabetes also offers the treating clinician the challenge of investing in their patient’s education and iden­tifying and addressing the lifestyle, social, and psychological impacts of the disease. Whilst the main aim of this chapter is to arrive at a working practical knowledge of diabetes, it will also raise awareness of the other glands, so that their dysfunction can be recognized and investigated where appropriate.
The Rise of Global Human Capital and the End of World Population Growth
Authors: Lutz Wolfgang , Samir KC
Published: November 2020

This is the first of three chapters that present the population projections by age, sex, and level of educational attainment for all countries in the world with a time horizon of 2060, and extensions to 2100. Before discussing the Wittgenstein Centre for Demography and Global Human Capital (WIC) projections, however, it is worth stepping back to consider how social structures change over time. While understanding the evolution of social structures is important under the conventional demographic approach that breaks down populations by age and sex, a more in-depth understanding of the changes in human capital requires that the interplay between different levels of schooling over time (the flow variable), and the changing educational attainment composition of the adult population (the stock variable) be taken into account. Societies can be stratified along several dimensions. In conventional social science the divisions studied refer to social class, race, or ethnicity. Demographers routinely break down populations by age and sex. Another important demographic dimension is that of birth cohorts or generations, that is, persons born and socialized during the same historical period. Particularly during periods of rapid social change, young cohorts tend to differ from older ones in important respects, and the demographic process of generational replacement is a powerful driver of socio-economic change. This process is analytically described by the theory of ‘Demographic Metabolism’, recently introduced as a generalized predictive demographic theory of socio-economic change by the first author (Lutz, 2013), building on earlier work by Mannheim (1952) and Ryder (1965). Ryder, who introduced the notion of Demographic Metabolism in a qualitative way, saw it as the main force of social change. While this theory applies to many stable human characteristics that are acquired at young age and remain invariant over a lifetime, it is particularly appropriate for studying and modelling the dynamics of the change in the distributions of highest educational attainment by age and sex over time. This perspective on human capital formation is the main focus of this book. This first of the three results chapters will highlight the results with respect to future population numbers by level of education in different parts of the world.
Information for all Seasons
Authors: Vedral Vlatko
Published: November 2020

Imagine that you arrive late at a party. Everyone is already there, sitting at a big round table. The host invites you to sit down with the others and you realize that they are engaged in what appears to be some kind of a game. The host tells you nothing other than to sit down and join in. Let’s say that you quite like playing poker, and you get excited at the prospect of participating, but you quickly realize that this is not poker. Then it dawns on you that you actually have absolutely no idea what is going on. You turn around to consult the host, but he seems to have disappeared. You take a deep breath and keep quiet, not wanting to reveal your ignorance quite so early in the evening, and you quietly continue to observe. The first thing you notice is that no one is allowed to utter any words, so it’s not obvious at all whether this is a game. This seems slightly odd but you think this may be one of the rules of the game and so you play along. You observe that the players are using a common deck of cards, resembling Tarot cards, each card with an elaborate picture on it, such as a warrior killing a lion, or a lady holding two crossed swords. After a while it becomes clear that players take turns to reveal a set of cards, one at a time. As each subsequent card is laid down, adjacent to the previous one, the other players closely observe the card being laid down as well as any body language of the player to further substantiate the meaning of the card. So it’s finally the turn of the player sitting next to you. He puts down a king standing over a dead lion with his sword raised above his head; you think to yourself, ‘Is this guy talking about a particular king who killed a lion?’, ‘Is he talking about royalty in general?’, or ‘Is this card a metaphor for some kind of personal triumph?’.
Murphy’s Law: I Knew this Would Happen to Me
Authors: Vedral Vlatko
Published: November 2020

Life now seems so robust that it becomes difficult to imagine how it could ever end. Are we now masters of our own destiny? With the robustness of biological information, combined with deliberate genetic engineering, are we capable of adapting to any environment Nature throws at us? Aside from some exceptional force majeure (in which case no payout is guaranteed) is there any condition under which life may end? One of the most topical and interesting discussions is whether life could run out of energy to function. But how could life ever run out of energy; and what does this actually mean? Are we just talking about the Sun dying or natural resources being depleted? The argument is that however life evolves in the future, it is difficult to imagine how it could run without the basic fuel. So if the Sun does die, we may find ourselves in a bit of pickle. However, in my view this hypothesis is entirely incorrect. At the end of the day, regardless of what happens in the Universe, the total energy is always conserved and it is merely our ability to process this energy that remains in question. Regardless of the Sun dying or natural resources being depleted, the same energy still exists within the Universe, and the challenge would then be to find different ways of harnessing it. My argument in this chapter is that life paradoxically ends not when it underdoses on fuel, but, more fundamentally, when it overdoses on ‘information’ (i.e. when it reaches a saturation point and can no longer process any further information). We have all experienced instances where we feel we cannot absorb any more information. The question is: is this fatal? What would you like the epitaph on your tombstone to read when you die? Usually people do not have a strong desire to inscribe anything grand or meaningful themselves, but their close ones, the family, friends, and relatives, choose to write something down to commemorate their loss.
Cradle Under the Canopy The Forest Origins of our Ape and Hominin Ancestors and the Tropical Forest Forays of the Genus Homo
Authors: Roberts Patrick
Published: November 2020

The evolutionary proximity of the non-human great apes to us is often stressed in studies of animals, such as Kanzi, a bonobo (Pan paniscus) bred in captivity, that demonstrate their capacity to undertake tool-use and even utilize and comprehend language (Toth et al., 1993; Savage-Rumbaugh and Lewin, 1996; Schick et al., 1999). Likewise, studies of chimpanzees (Pan spp.) have highlighted the similarity of their emotional and empathetic capacities to those of humans (Parr et al., 2005; Campbell and de Waal, 2014). However, as noted by Savage- Rumbaugh and Lewin (1996), in palaeoanthropology and archaeology more broadly, the emergence of the hominin clade and, later, our species, is referenced in terms of the ‘chasm’ between ourselves and other extant great apes. Indeed, despite our genetic and behavioural proximity, extant non-human great ape taxa are often popularly characterized as living fossils of how we used to be. They are used as analogues for the subsistence and behaviour of the Last Common Ancestor (LCA) of humans and non-human great apes (Clutton-Brock and Harvey, 1977; Goodall, 1986; Foley and Lewin, 2004) and it is almost as if the fact that they still occupy the tropical environments in which these hominoids likely evolved (though see Elton, 2008) allows them to be treated as static comparisons (Figure 3.1). Since Darwin wrote the Descent of Man in 1871, the forests of the tropics, and their modern non-human great ape inhabitants, have tended to be perceived as being left behind as the hominin clade gained increasingly ‘human’ traits of tool-use, medium to large game hunting, and upright locomotion on open ‘savanna’ landscapes (Dart, 1925; Potts, 1998; Klein, 1999). From this perspective it is perhaps unsurprising that tropical forests are seen as alien to the genus Homo and its closest hominin ancestors.
Conclusion: A lived Neolithic
Authors: Ray Keith , Thomas Julian
Published: November 2020

Why is the Neolithic period in Britain of continuing importance today? For one thing, as we observed in the Introduction to this book, places like Stonehenge, Avebury, and the components of the Heart of Neolithic Orkney World Heritage Site such as Skara Brae, the Stones of Stenness, and the Ness of Brodgar provide an enduring fascination for a wide public, and therefore attract visitors from around the world (even if they don’t arrive presidentially, as Obama did). Confronted with these spectacular but enigmatic remains, it is inevitable that visitors will find themselves looking, and often struggling, for explanations that meet their expectations of the real world. Most obviously, they want to know who made these things, and why. Beyond this, many visitors also want to identify where these people came from, what mattered to them most in their lives, and, perhaps most important of all, how they are connected to those of us inhabiting ‘their’ space, however much it has changed, today. But an equally important issue is that the way we view the Neolithic can have important ramifications for our understanding of the contemporary world, and how it came into being. For example, the adoption of farming appears to have been an escalating process from which British societies have been unable to extricate themselves, and that has led to environmental degradation and other modern ills. But it has also been a process that has shaped our perception of the landscape, and of what is ‘natural’ in our environment. And while the majority of us live a metropolitan way of life in contemporary Britain, our everyday language nonetheless remains full of reference to the land and its working. The popular answers to the ‘whys’ of the Neolithic of Britain have been legion, ranging from the pre-industrial folk stories making intelligible the chambered mounds as giant’s graves or fairy caves, to antiquarian invocations of Merlin or the Druids, and more recent suggestions of priestly astronomers. Equally, as we saw in Chapter 1, each generation of academic archaeologists has brought new conceptual resources to bear on Neolithic Britain, and has come up with novel interpretations.
Take Two Aspirin
Authors: Smith Gary
Published: November 2020

IBM’s Watson got an avalanche of publicity when it won Jeopardy, but Watson is potentially far more valuable as a massive digital database for doctors, lawyers, and other professionals who can benefit from fast, accurate access to information. A doctor who suspects that a patient may have a certain disease can ask Watson to list the recognized symptoms. A doctor who notices several abnormalities in a patient, but isn’t confident about which diseases are associated with these symptoms, can ask Watson to list the possible diseases. A doctor who is convinced that a patient has a certain illness can ask Watson to list the recommended treatments. In each case, Watson can make multiple suggestions, with associated probabilities and hyperlinks to the medical records and journal articles that it relied on for its recommendations. Watson and other computerized medical data bases are valuable resources that take advantage of the power of computers to acquire, store, and retrieve information. There are caveats though. One is simply that a medical data base is not nearly as reliable as a Jeopardy data base. Artificial intelligence algorithms are very good at finding patterns in data, but they are very bad at assessing the reliability of the data and the plausibility of a statistical analysis. It could end tragically if a doctor entered a patient’s symptoms into a black-box data-mining program and was told what treatments to use, without any explanation for the diagnosis or prescription. Think for a moment about your reaction if your doctor said, I don’t know why you are ill, but my computer says, “Take these pills.” I don’t know why you are ill, but my computer recommends surgery. Any medical software that uses neural networks or data reduction programs, such as principal components and factor analysis, will be hard-pressed to provide an explanation for the diagnosis and prescribed treatment. Patients won’t know. Doctors won’t know. Even the software engineers who created the black-box system won’t know. Nobody knows. Watson and similar programs are great as a reference tool, but they are not a substitute for doctors because: (a) the medical literature is often wrong; and (b) these errors are compounded by the use of data-mining software.
Digital media and intellectual property
Authors: Baecker Ronald M.
Published: November 2020

Vannevar Bush envisioned a machine that would assist humanity in the creative work of writing. Doug Engelbart imagined the collaborative sharing and enhancement of knowledge. Digital media today—text, drawings, photos, audio, and video—surpass the visions of their pioneers. These media may be copied, shared, and modified in ways that challenge the legal system, because unrestricted content sharing without suitable payment to creators runs counter to intellectual property (IP) traditions and laws. Writers, musicians, artists, and inventors have long relied upon IP protection to enable them to control the use of their creations and inventions. Copyright infringement, that is, copying in violation of copyright, threatens the income that they could receive from their creations. The concept of fair use is a critical issue in such discussions, as it allows certain exceptions to copyright. One area that has received a great deal of attention is the digital copying and sharing of music; we shall examine the interplay between conventional behaviour, ethics, technical interventions to limit or block copying, laws and legal battles, and product and pricing innovation. Next, we shall look at similar issues in the domain of motion pictures. There are effective and legal streaming services, yet there are still concerns about copyright infringement. Copyright holders now automatically produce takedown notices to insist that websites remove illegally or improperly sourced material. Such notices include many errors, causing additional complications for video creators. One interesting challenge to the concept and laws of copyright occurs in the creation of mash-ups. Artists use fragments from existing musical or visual performances as well as their own material to create audio-visual works that combine multiple content sources. Artists, lawyers, and businesspeople debate the extent to which such mash-ups violate reasonable copyright protection. Copyright is also significant for academic articles and textbooks. There are two especially interesting cases to discuss. One is the widespread copying of textbooks by students due to the high price of texts. The other is the fair pricing of the publication of research results that have been funded by government grants. This issue has provided one of several stimuli to the creation of open access publications.
Law and order, war and peace
Authors: Baecker Ronald M.
Published: November 2020

Most computers during the Second World War, such as the British code-breaking Colussus machine, had been developed for military use. The effects on law and order and war and peace of computerization, worldwide telecommunications, social media, artificial intelligence (AI), and robotics is the topic of Chapter 6. As in Chapter 5, the most compelling visions of the potential opportunities and dangers have been in science fiction and in film; we begin the chapter by reviewing some memorable examples. We then discuss how technology is used by the police, such as the use of video evidence to sometimes exonerate the police against false accusations of needless brutality. We also examine how citizens are using social media to protect themselves and alert others to what they believe is unwarranted violence or unjust actions by law enforcement. We expand upon Section 5.7’s discussion of citizen mobilization by social media with the goal of regime change. In this context, we discuss how the government (especially police and security services) gains leverage via the surveillance of the digital information and communications of citizens. This surveillance has significantly increased due to security concerns post-9/11. We will examine these developments in the USA, Canada, and the UK, as well as in other parts of the world. We shall also discuss cases of organizations trying to subvert societies that repress and forbid access to the internet, with the goal of enabling its citizens to access the internet freely. Next, we consider ways in which tools of digital disruption are used by a country or government or a set of individuals against others. The timely and current case study explored is on governmental use of hacking and other aggressive digital means to interfere with the electoral processes of another country, or even to disrupt or destabilize the other country. At the extreme, governments engage in cyberterrorism or even cyberwar­fare. We shall discuss several recent examples of this and argue that weapons of cyberwar­fare could be as catastrophic as nuclear or biological weapons. The technology of warfare has also evolved.
Privacy
Authors: Baecker Ronald M.
Published: November 2020

Fears about loss of privacy in computerized societies have been central to dystopian literature. The issue has also concerned thoughtful computer scientists and lawyers since the 1960s. By then, the scope of the computer revolution was making clear that governments and corporations could keep records about almost every aspect of our lives. As data storage became virtually limitless at trivial cost, effective uses of data grew, as did risks to personal privacy. We shall define privacy, look at its manifestations and roles, and discuss current and future threats to it. We shall introduce concepts that are key to understanding privacy, such as informed consent. A major concern is the threats to information privacy or data privacy, in which a person’s confidential information has errors or becomes exposed to people who should not be able to see or use it. We shall examine situations in which privacy can be invaded by governments, organizations, and individuals. Governments amass vast stores of personal data during the everyday course of administration and regulation. Government surveillance in many nations captures information that should be private, a topic we discussed in Chapter 6. Search engines, credit rating organizations, and insurance companies also gather huge amounts of data on consumers. When data is incorrect, or is hacked, there are serious implications for information privacy. Criminals seek to gain leverage by ferreting out computer-based data about personal financial transactions. Health information is a particularly sensitive area in which many people feel especially vulnerable. These are all ‘classical’ privacy concerns, the dangers of which were evident in the 1960s. New technologies have raised more concerns. Social media holds vast quantities of personal data that we have willingly disclosed, including information that could prove embarrassing later in life. A vivid example of a privacy breech was the Cambridge Analytica/Facebook scandal of 2018. New technologies raise new privacy concerns. Chips use GPS to track our location and movements. Recent advances in computer vision and the widespread deployment of video cameras enable face recognition. Chips located in the environment and embedded as sensors and prostheses in our bodies make our activities and even our moods accessible by others.
Automation, work, and jobs
Authors: Baecker Ronald M.
Published: November 2020

The effect of automation on employment and jobs has engaged thoughtful computer scientists and economists since the earliest days of computing. Yet there have been concerns about the effects of technology on employment since ancient times, and notably during the First Industrial Revolution in the nineteenth century by a group of workers known as the ‘Luddites’. Our first topic is the role of algorithms in enabling more efficient processing of job applicants and the selection of candidates to interview. This now includes the automatic filtering out of huge numbers of résumés that are never seen by human resource professionals. Next, we look at how technology is used in monitoring job performance, with the goal of encouraging or requiring enhanced performance. Oftentimes, these practices have the opposite effect, as it makes workers feel like ‘Big Brother’ is watching. Companies have long used contractors to provide flexibility in the availability of workers as well as to circumvent costs such as medical benefits and liabilities such as severance pay. This practice has recently changed dramatically: internet communication can now rapidly link seekers of services to providers of the services. This is typically called the gig economy or sharing economy, yet a better name is on-demand services. We shall then examine areas where automation threatens to replace human workers with machines. Fear is rampant, as typified by a 2017 New York Times article, ‘Will Robots Take Our Children’s Jobs?’ Between 2014 and 2016, future prospects were analysed in five scholarly books. We examine the phenomenon of unemployment by looking at specific areas: agriculture, manufacturing, service industries, and the professions. We highlight how new robotic technology, incorporating sensing, reasoning, and manipulating abilities, is enabling significant automation. Of particular importance is the extent to which new machine learning systems are enabling the automation of thinking and reasoning, which were previously considered infeasible for machines. Arguably the most interesting, challenging, and risky application is that of automatic diagnosis of disease, and, more speculatively, robot doctors.
Epilogue
Authors: Baecker Ronald M.
Published: November 2020

In the preceding pages, we have introduced, explained, and discussed a large and growing number of ways in which digital technologies are affecting our world. The pace of change is accelerating. Although there are concerns that semiconductor performance and miniaturization will soon no longer obey Moore’s Law (discussed in the Prologue), new technologies such as quantum computers will likely extend the continual improvement of hardware performance. New software approaches such as deep learning have dramatically improved increasingly critical artificial intelligence (AI) computations. Concerns about employment prospects as well as the fascination of computer science have greatly enlarged the talent pool of individuals studying this field or related disciplines and adopting careers involving digital technologies. Corporations now understand the importance of computing, and of investing in research and development. Finally, the astronomical returns yielded by high-tech ‘start-ups’ such as Apple, Google, Facebook, and Amazon have led to enormous pools of investment capital seeking new digital technology innovations. As a result, there are now many social, legal and policy, and moral and ethical issues regarding digital technology and its presence in human society. We have discussed these topics in depth in the preceding pages. To review, we shall now highlight the most important issues. We shall classify the issues under either a social, policy/legal, or ethical/moral heading, yet all three categories are closely related. A social issue is a statement about quality of life, and what kind of world we want to live in. A policy or legal choice is a statement about the way we are governed, and about the rules we adopt as societies to shape the world as we intend. An ethical or moral dilemma is a question that societies, organizations, and individuals must answer and support with appropriate actions and laws to create a world that is fair, just, and good. There are no easy answers. The eminent professor and historian of technology Melvin Kranzberg described this in what he called Kranzberg’s First Law: ‘Technology is neither good nor bad; nor is it neutral.’
Empirical Orthogonal Functions
Authors: van den Dool Huug
Published: November 2020

The purpose of this chapter is to discuss Empirical Orthogonal Functions (EOF), both in method and application. When dealing with teleconnections in the previous chapter we came very close to EOF, so it will be a natural extension of that theme. However, EOF opens the way to an alternative point of view about space–time relationships, especially correlation across distant times as in analogues. EOFs have been treated in book-size texts, most recently in Jolliffe (2002), a principal older reference being Preisendorfer (1988). The subject is extremely interdisciplinary, and each field has its own nomenclature, habits and notation. Jolliffe’s book is probably the best attempt to unify various fields. The term EOF appeared first in meteorology in Lorenz (1956). Zwiers and von Storch (1999) and Wilks (1995) devote lengthy single chapters to the topic. Here we will only briefly treat EOF or PCA (Principal Component Analysis) as it is called in most fields. Specifically we discuss how to set up the covariance matrix, how to calculate the EOF, what are their properties, advantages, disadvantages etc. We will do this in both space–time set-ups already alluded to in Equations (2.14) and (2.14a). There are no concrete rules as to how one constructs the covariance matrix. Hence there are in the literature matrices based on correlation, based on covariance, etc. Here we follow the conventions laid out in Chapter 2. The post-processing and display conventions of EOFs can also be quite confusing. Examples will be shown, for both daily and seasonal mean data, for both the Northern and Southern Hemisphere. EOF may or may not look like teleconnections. Therefore, as a diagnostic tool, EOFs may not always allow the interpretation some would wish. This has led to many proposed “simplifications” of the EOFs, which hopefully are more like teleconnections. However, regardless of physical interpretation, since EOFs are maximally efficient in retaining as much of the data set’s information as possible for as few degrees of freedom as possible they are ideally suited for empirical modeling. Indeed EOFs are an extremely popular tool these days.
Tracing the Trace: Photography, the Index, and the Limits of Representation
Authors: Hauser Kitty
Published: November 2020

Photography, as is well known, is the image-making technology which specializes in the freezing of time.1 What kind of historiography, then, might photography be said to embody? How can photography, with its ineluctable connection to the present moment, hope to say anything at all about the past—about either the broad processes of history or even the events of the hours and minutes immediately preceding the second in which the photograph is taken? What kinds of knowledge of the past does photography allow, and what does it disallow? How can photography, that most superficial of media, hope to become a vehicle for the archaeological imagination, with its love of immanent depths? If photographic technology is uniquely equipped to record (visually) the present moment, it is also characterized—famously—by its thorough and indiscriminate recording of surface detail. What it lacks in temporal depth it makes up for in this meticulous rendering of appearances; any surface marked by the effects of action or time can be faithfully recorded by this technology which itself produces the marked surfaces of photographic plate, film, or print. History and the passing of time is available to photography only in the form of its traces, the more-or-less legible marks and remnants it has left behind at any one moment in the world. And it is precisely photography’s own nature as a chemical trace (until digitization, at least) that enables it accurately to reproduce these marks and signs of history. As discussed in Chapter 1, since the nineteenth century (at least) historical sciences such as palaeontology, geology, and archaeology have based themselves upon the reading of such signs of the past in the present, and this broad epistemological model could be extended to include military reconnaissance, forensic science, and art connoisseurship. Photography, fixing these signs in an image, has had—unsurprisingly, perhaps—an important part to play in the historical development of these disciplines. Photography meets the archaeological imagination as soon as photographic images are scanned for historical information in these disciplines and practices. In a sense, however, photography cannot help but represent the world archaeologically, since it cannot help but record its objects and landscapes in a temporal context, the traces of the past scattered across their surfaces. Ruskin enthused over this quality of the new medium.
Wave and tidal power
Authors: Millar Dean L.
Published: November 2020

This chapter reviews how electricity can be generated from waves and tides. The UK is an excellent example, as the British Isles have rich wave and tidal resources. The technologies for converting wave power into electricity are easily categorized by location type. 1. Shoreline schemes. Shoreline Wave Energy Converters (WECs) are installed permanently on shorelines, from where the electricity is easily transmitted and may even meet local demands. They operate most continuously in locations with a low tidal range. A disadvantage is that less power is available compared to nearshore resources because energy is lost as waves reach the shore. 2. Nearshore schemes. Nearshore WECs are normally floating structures needing seafloor anchoring or inertial reaction points. The advantages over shoreline WECs are that the energy resource is much larger because nearshore WECs can access long-wavelength waves with greater swell, and the tidal range can be much larger. However, the electricity must be transmitted to the shore, thus raising costs. 3. Offshore schemes. Offshore WECs are typically floating structures that usually rely on inertial reaction points. Tidal range effects are insignificant and there is full access to the incident wave energy resource. However, electricity transmission is even more costly. Tidal power technologies fall into two fundamental categories:1. Barrage schemes. In locations with high tidal range a dam is constructed that creates a basin to impound large volumes of water. Water flows in and out of the basin on flood and ebb tides respectively, passing though high efficiency turbines or sluices or both. The power derives from the potential energy difference in water levels either side of the dam. 2. Tidal current turbines. Tidal current turbines (also known as free flow turbines) harness the kinetic energy of water flowing in rivers, estuaries, and oceans. The physical principles are analogous to wind turbines, allowing for the very different density, viscosity, compressibility, and chemistry of water compared to air. Waves are caused by winds, which in the open ocean are often of gale force (speed >14 m/s).
Photovoltaic and photoelectrochemical conversion of solar energy
Authors: Grätzel Michael
Published: November 2020

The Sun provides about 100,000 Terawatts (TW) to the Earth, which is approximately ten thousand times greater than the world’s present rate of energy consumption (14 TW). Photovoltaic (PV) cells are being used increasingly to tap into this huge resource and will play a key role in future sustainable energy systems. Indeed, our present needs could be met by covering 0.5% of the Earth’s surface with PV installations that achieve a conversion efficiency of 10%. Fig. 8.1 shows a simple diagram of how a conventional photovoltaic device works. The top and bottom layers are made of an n-doped and p-doped silicon, where the charge of the mobile carriers is negative (electrons) or positive (holes), respectively. The p-doped silicon is made by ‘doping’ traces of an electron-poor element such as gallium into pure silicon, whereas n-doped silicon is made by doping with an electron-rich element such as phosphorus. When the two materials contact each other spontaneous electron and hole transfer across the junction produces an excess positive charge on the side of the n-doped silicon (A) and an excess negative charge on the opposite p-doped (B) side. The resulting electric field plays a vital role in the photovoltaic energy conversion process. Absorption of sunlight generates electron-hole pairs by promoting electrons from the valence band to the conduction band of the silicon. Electrons are minority carriers in the p-type silicon while holes are minority carriers in the n-type material. Their lifetime is very short as they recombine within microseconds with the oppositely charged majority carriers. The electric field helps to collect the photo-induced carriers because it attracts the minority carriers across the junction as indicated by the arrows in Fig. 8.1, generating a net photocurrent. As there is no photocurrent flowing in the absence of a field, the maximum photo-voltage that can be attained by the device equals the potential difference that is set up in the dark at the p-n junction. For silicon this is about 0.7V. So far, solid-state junction devices based on crystalline or amorphous silicon (Si) have dominated photovoltaic solar energy converters, with 94% of the market share.
Fuel cells
Authors: Jollie David
Published: November 2020

The vision of a world without oil or other fossil fuels is both surreal and at the same time seductive as a solution to current concerns over climate change and oil availability. It is also, to some extents, an irrelevant one for fuel cells. Rather than being an energy source they provide a mechanism for transforming one form of energy (chemical) to another (typically electricity or heat). In this way, they resemble batteries, internal combustion engines, and even steam engines. The key to their value is really their efficiency: they are able to carry out this transformation cleanly and efficiently. Fuel cells are not yet fully developed. The technology and the fuel cell effect were discovered in 1839 by, depending on your point of view, William Grove or Christian Schoenbein (Sanstede et al., 2003). For a long time after this, the technology was essentially dormant until the 1940s when Francis Bacon started working on it and the 1950s when Allis-Chalmers built the first application of the technology (a fuel cell powered tractor). Research and development accelerated when fuel cells were chosen as power sources for space missions in the 1960s and the 1970s oil price shocks increased interest in other technologies, but the real impetus came in the 1990s when DaimlerChrysler examined the proton exchange membrane fuel cell and decided that it could be used to power a vehicle. Considerable effort is still to be expended on improving fuel cell technology in terms of cost and performance. Ancillary questions like the best method of fuelling and of carrying fuel still remain to be solved. However, we have begun to see fuel cells entering the commercial marketplace and the coming years and decades should see this accelerate. A simple definition of a fuel cell might be ‘a device that reacts a fuel and an oxidant, without combustion, producing heat and electricity’. The best-known case, that of a proton exchange membrane (PEM) fuel cell (PEMFC), is illustrated in Fig. 11.1. In a PEM fuel cell, the fuel is hydrogen, the oxidant is oxygen and the only chemical product is water, as described in reaction (1): . . . 2H2 + O2 ⇒ 2H2O + heat + electricity (11.1) . . .
Conservation biology: unsolved problems and their policy implications
Authors: Dobson Andy , Turner Will R.
Published: November 2020

A plot of the number of parks and other terrestrial protected areas established around the world over the past 100 years exhibits near-exponential growth, with marine parks following a similar trend. This is a testament to the growing recognition of the importance of sustaining natural systems worldwide. Yet, at the same time an expanding human population and the desire of all people for a more prosperous life have resulted in unprecedented rates of deforestation and habitat conversion. Accompanying these changes has been the spread of invasive, non-native species (including new disease organisms) to virtually all parts of the globe. With recent assessments placing 12% of the world’s birds, 23% of mammals, and 32% of amphibians in danger of extinction (Baillie et al., 2004), conservationists feel a justifiable sense of panic. Any attempt to measure the full extent of the current biodiversity crisis is made immensely more difficult by our astounding lack of knowledge about the species that share this planet with us. For example, we do not know within an order of magnitude the number of species currently present on Earth (May, 1988, 1992; Novotny et al., 2002); estimates range from 3 to more than 30 million species, of which only 1.5–1.8 million have been described to date. Not surprisingly, our inventory of the more charismatic groups of organisms, such as birds, mammals, and butterflies, is vastly more complete than our inventory of insects, arachnids, fungi, and other less conspicuous but no less important groups. If we ask the logical follow-up question—what proportion of known (described) species is in danger of extinction?—we run into a similar barrier. While organizations like the World Conservation Union (IUCN) have prepared reasonably complete assessments for a few groups, notably the charismatic vertebrates, most species are too poorly known to assess. Even within the USA only about 15% of the species catalogued to date are sufficiently known to be given any sort of conservation rank, such as endangered or not endangered (Wilcove and Master, 2005); among invertebrates that value drops to less than 5%. Compounding this shortfall of data is an equally serious shortfall of money.
Perspective
Authors: Zalasiewicz Jan
Published: November 2020

The purest of science fiction. The Earth, in a post-human future, many millions of years hence, being re-explored. By . . . whom? Perhaps extraterrestrial explorers or colonists, just as we now peer at images of rock strata sent back by the Mars landers. Or perhaps a new, home-grown intelligence: say, a newly evolved species of hyper-intelligent rodent. No matter. What would such explorers, of whatever ancestry, find of our own, long-vanished, human empire? A frivolous question, perhaps. But perhaps not. It is hard, as humans, to get a proper perspective on the human race. We know that the Earth has a history that is long beyond human imagination, and that our own history is tiny by comparison. We know that we are animals, and yet we have transcended our natural environment to live in surroundings that, mostly, we have manufactured for ourselves. We know that this created environment is evolving at a speed that is vastly more rapid than the normal evolution of biological organisms or communities. We do not understand, quite, how our created environment and our activities interact with the natural environment, and we do not know what the long-term consequences will be. Let us take one view. We are simply one species out of perhaps 30 million currently inhabiting the planet (reputable estimates range from some 5 million to over 100 million). We are briefly in the golden age of our power, our dominance. But we are destined to extinction also, just as the dinosaurs became extinct. The world will then go on as before. Once a geological age or two has passed, there will be nothing but the odd bone or gold ring to show that we were ever here. In this scenario, comparison with the dinosaurs is apt. They were the top predators of their day, as our single species is now. But consider, also, the differences between us and the dinosaurs. The dinosaurs existed on this Earth for about a hundred million years, and included many species adapted to different environments. Homo sapiens is but one species, and has been around for less than a quarter of a million years, less than a tenth of an average species’ longevity.
Before the Stone Age Existed
Authors: O'Connor Anne
Published: November 2020

What is the difference between temptation and geological time? The one is a wile of the devil and the other is a devil of a while. (Dawkins to Hughes, 17 March 1870: SMC: TMH) In the early eighteenth century, John Conyers, an apothecary and antiquary of London, discovered the body of an elephant as he was digging for gravel at Gray’s Inn Lane. Nearby lay a flint implement (Fig. 1.1). Today we might well call his elephant a ‘mammoth’ and refer the implement to the ‘Palaeolithic’ period; in 1715, however, Conyers’s beast was dated to the reign of Claudius, the Roman Emperor. This was the belief of John Bagford, an old friend of Conyers, a bookseller and one of the founder members of a tavern-based antiquarian club that was soon to become the Society of Antiquaries of London. At the time, a Roman elephant attacked by an Ancient Briton seemed a likely scenario to account for the curious occurrence of this animal in London, far from its hot and distant homeland. It would be a century and a half later when our ancestors were acknowledged as the contemporaries of such enormous animals: they would then be pictured in a newly-discovered geological world, more ancient than the time of the Romans or even the British natives described by Caesar. For Bagford and his contemporaries, the time allotted to humans, and even to the Earth itself, was not long. Their knowledge about the distant past was gathered from folklore or historical texts, and the Bible supplied a particularly important source of chronological information. Back in the seventeenth century, James Ussher (1581–1656) had famously calculated the age of the Earth and the Creation to date to 4004 BC. But Ussher did not, as is often believed, reach this date by counting back through the generations of the Bible; indeed, he could not. As John Fuller has observed, there is no fixed point from which to start counting: a vague gap divides the last of the Hebrew books from the year AD 1.
Antiquities and Political Prestige in the Early Modern Era
Authors: Diaz-Andreu Margarita
Published: November 2020

Television programmes about archaeology, the Asterix series on many children’s bookshelves, Celtic-flavoured holidays in Ireland, the megalomaniacal classical style in the business buildings erected since the late 1980s—all these tell us about the enduring popularity of the past in people’s minds. The intellectual ‘other side of the coin’ are the departments of archaeology, museums of archaeology, and heritage departments operating all over the world. This interest in the past is certainly not new. Whereas the latter—the museums, university and heritage departments—only appeared in the urban landscape less than two hundred years ago, by then several generations of intellectuals with knowledge in the arts had been aware of the existence of an ancient past. A Doric folly on the bank of the river overlooked by the cathedral in the pretty city of Durham was built in 1830 by a Polish count and the eighteenth-century estate of La Alameda de Osuna on the outskirts of Madrid, with its Greek-inspired temple of love with a statue of Bacchus (substituting the original Venus statue that had been taken by the Napoleonic troops on their withdrawal to France)—are only two examples of my own personal daily encounter with the past I have had at diVerent periods in my life. Yet, a different type of past is also familiar to me, a past that is more related to the nation’s past. In La Alameda de Osuna estate, in addition to its many classical features, there is an eighteenth-century copy of a medieval hermit’s chapel, and a country house which used to have displayed automatons in traditional dress. In the seventeenth century a beautiful Gothic-style font cover was made for Durham cathedral illustrating a continuity with a medieval past. Many other examples could be added. All of them illustrate an obsession with the past which on the one hand has lasted at least several centuries. On the other, however, they also appear to indicate an initial quasi-fixation with the classical period, which gradually became counter-balanced by an appeal to each country’s past. This reveals a continuous transformation in time and space in the discourse of the past.