bluuebunny/crossref_metadata_2025 huggingface dataset:
Biodiversity Along Core–Periphery Clines
Authors: Volis Sergei , Kark Salit
Published: November 2020

The study of biodiversity has received wide attention in recent decades. Biodiversity has been defined in various ways (Gaston and Spicer, 1998, Purvis and Hector 2000, and chapters in this volume). Discussion regarding its definitions is dynamic, with shifts between the more traditional emphasis on community structure to emphasis on the higher ecosystem level or the lower population levels (e.g., chapters in this volume, Poiani et al. 2000). One of the definitions, proposed in the United Nations Convention on Biological Diversity held in Rio de Janeiro (1992) is “the diversity within species, between species and of ecosystems.” The within-species component of diversity is further defined as “the frequency and diversity of different genes and/or genomes . . .” (IUCN 1993) as estimated by the genetic and morphological diversity within species. While research and conservation efforts in the past century have focused mainly on the community level, they have recently been extended to include the within-species (Hanski 1989) and the ecosystem levels. The component comprising within-species genetic and morphological diversity is increasingly emphasized as an important element of biodiversity (UN Convention 1992). Recent studies suggest that patterns of genetic diversity significantly influence the viability and persistence of local populations (Frankham 1996, Lacy 1997, Riddle 1996, Vrijenhoek et al. 1985). Revealing geographical patterns of genetic diversity is highly relevant to conservation biology and especially to explicit decision-making procedures allowing systematic rather than opportunistic selection of populations and areas for in situ protection (Pressey et al. 1993). Therefore, studying spatial patterns in within-species diversity may be vital in defining and prioritizing conservation efforts (Brooks et al. 1992). Local populations of a species often differ in the ecological conditions experienced by their members (Brown 1984, Gaston 1990, Lawton et al. 1994). These factors potentially affect population characteristics, structure, and within-population genetic and morphological diversity (Brussard 1984, Lawton 1995, Parsons 1991). The spatial location of a population within a species range may be related to its patterns of diversity (Lesica and Allendorf 1995). Thus, detecting within-species diversity patterns across distributional ranges is important for our understanding of ecological and evolutionary (e.g., speciation) processes (Smith et al. 1997), and for the determination of conservation priorities (Kark 1999).
Linking Species Diversity and Landscape Diversity
Authors: Boeken Bertrand , Oren Yarden
Published: November 2020

Ecologists generally agree that species diversity is linked to landscape features (Pickett and White 1985, Glenn et al. 1992, Wiens et al. 1993, Rosenzweig 1995, Hoagland and Collins 1997, Ritchie and Olff 1999). We present a conceptual framework for connecting species diversity and landscapes by showing how changes in species assemblages and changes in landscape structure coincide. We focus on the dynamics of the mutual relationship between (1) the frequency of occurrence of the various landscape mosaic components (patches) and their properties in terms of abiotic conditions, resource availabilities, and structural features, and (2) the occurrence and abundance of the species of an assemblage within and among these components. Although we use examples of assemblages of annual plants in semiarid shrubland, we stress the generality of our approach and its applicability to many other groups of organisms and landscapes. Most ecologists would also agree that there are connections between the observations that (1) individuals and populations of organisms are affected by environmental heterogeneity in the landscape, (2) species assemblages (or communities) consist of populations (or parts of them), and (3) changes in the landscape affect species assemblages, and vice versa. In this chapter we explore this often intuitive relationship explicitly. Our basic premise is that species assemblages are collections of populations interacting with the heterogeneity of the landscape. We use the term “assemblage” to preclude assumptions about interactions and proximity or encounters among the organisms. Simple presence in the sampled landscape is the criterion for belonging to an assemblage; the landscape mosaic is an assemblage of patches, which, like species, may or may not interact. We assume that the landscape is heterogeneous, comprising a mosaic of distinct patches, which can be distinguished by some patch property. Our approach does not require a particular size or kind of landscape, but its scale and structure and the definition of patches have to be relevant for the distribution of the organisms whose diversity we study. In this chapter we discuss the functional connection between the dynamics of landscapes and of species assemblages.
Properties of Relativistic Mean-Field Theory
Authors: Dyall Kenneth G. , Faegri Knut
Published: November 2020

We have previously seen how the Dirac equation for one particle requires some rather special consideration and interpretation in order to arrive at a form that is able to treat electrons and positrons on an equal footing. These problems persist also when we go to systems with more than one electron. One might think that the extension to several electrons should not introduce dramatic changes. After all, we noted that even the one-electron problem must be viewed as a many-electron (and -positron) system in order to arrive at a consistent description. The problem with introducing more electrons is that electron–electron interactions that were previously small—for the one-electron case typically arising from vacuum polarization and self-interaction—now occur to the same order as the kinetic energy and the interaction with the potential. So while a perturbative approach such as QED can use the solutions of the one-electron Dirac equations as a very good starting approximation to a more accurate description of the full system, the same would not work for a system with more electrons because it would mean neglecting interactions of the same magnitude as the zeroth-order energy. For applications to quantum chemistry, the treatment of the entire electron–electron interaction as a perturbation would be hopelessly impractical, as it is even in manyelectron relativistic atomic structure calculations. The technique for dealing with this problem is well known from nonrelativistic calculations on many-electron systems. One-particle basis sets are developed by considering the behavior of the single electron in the mean field of all the other electrons, and while this neglects a smaller part of the interaction energy, the electron correlation, it provides a suitable starting point for further variational or perturbational treatments to recover more of the electron–electron interaction. It is only natural to pursue the same approach for the relativistic case. Thus one may proceed to construct a mean-field method that can be used as a basis for the perturbation theory of QED.
Molecular Properties
Authors: Dyall Kenneth G. , Faegri Knut
Published: November 2020

Strictly speaking, in quantum mechanics a measurable property is defined as an observable connected to a self-adjoint operator. However, in common usage the term molecular property is loosely taken to mean any physical attribute of a molecule, preferably amenable to experimental measurement. Common examples of properties of interest to chemists are molecular structure, thermodynamic quantities, spectroscopic transition energies and intensities, and various electric and magnetic moments. The amenability to experiment may exist only in principle—one of the strong points of modern computational chemistry is the possibility of studying phenomena occurring under conditions that lie beyond the present experimental capabilities. Sometimes, differential effects between different theoretical models are also regarded as properties: thus the correlation energy is generally considered to be the difference between the Hartree–Fock energy and the energy obtained from a complete many-electron treatment (e.g. full CI or MBPT to all orders). At best only the latter of these is accessible to experiment. Similarly, certain relativistic effects (e.g. bond contraction) only appear as the difference between results from a relativistic and a nonrelativistic calculation. The calculation of molecular properties in a relativistic framework follows the same principles as for the nonrelativistic case once a wave function or electron density of adequate quality is available. Our aim here is therefore not to provide explicit expressions and formulas for the calculation of a more or less complete catalog of properties. However, in relativistic calculations of molecular properties there are some aspects of the theory that warrant special care and consideration. In particular, we need to know how to handle features such as Lorentz invariance, gauge invariance, and negativeenergy states. Moreover, the electric and magnetic fields appear as natural parts of the relativistic Hamiltonian, and we therefore expect that properties involving these may require a different treatment from the nonrelativistic case where terms involving external fields are grafted onto the nonrelativistic Hamiltonian, often based on some reduction or approximation from the relativistic case.
Unitary Transformations of the Dirac Hamiltonian
Authors: Dyall Kenneth G. , Faegri Knut
Published: November 2020

The separation of the spin-dependent terms in the Dirac Hamiltonian enables us to make an approximation in which the spin-free terms are included in the orbital optimization and the spin-dependent terms may be treated later as a perturbation. In this process, the parameter space required to treat the large and small components has not changed. Even with the extraction of (σ ·p) from the small component, we still have to calculate integrals involving pfL, which essentially regenerates the original small component space and so the integral work has not really changed. What has been achieved is the ability to use the machinery of spin algebra from nonrelativistic theory, but we are left with a large and a small component. The obvious next step is to separate the large and small components, or the positiveand negative-energy states. The small component can be eliminated from the Dirac equation by algebraic manipulation, but this leaves the energy in the denominator. It would be preferable to obtain an energy-independent Hamiltonian that acted only on positive-energy states and that could therefore be represented as two-component spinors. If, following this separation, it were possible to separate out the spin-free and spin-dependent terms, we would have a spin-free Hamiltonian that would operate on a one-component wave function, and we would then be able to use all the machinery of nonrelativistic quantum chemistry but with modified one- and two-electron integrals. The matrix form of the Dirac Hamiltonian suggests that we should seek a unitary transformation that will make it diagonal with respect to the large- and small-component spinor spaces. Such a transformation is called a Foldy–Wouthuysen transformation (Foldy and Wouthuysen 1950). Although in their original paper only the free-particle transformation was derived, together with an iterative decoupling procedure that will be described later in this chapter, the term Foldy–Wouthuysen transformation has come to mean any unitary transformation that decouples the large and small components, either exactly or approximately, and we will use it in this sense.
Soil Quality in Vineyards
Authors: White Robert E.
Published: November 2020

The soil must provide a favorable physical environment for the growth of vines—their roots and beneficial soil organisms. Some of the important properties con­tributing to this condition are infiltration rate, soil strength, available water ca­pacity, drainage, and aeration. Ideally, the infiltration rate IR should be >50 mm/hr, allowing water to enter the soil without ponding on the surface, which is predisposed to runoff and erosion. The range of infiltration rates for soils of different texture and structural condi­tion is shown in table 7.1. Typically, the soil aggregates should have a high de­gree of water stability so that when the soil is subjected to pressure from wheeled traffic or heavy rain, the aggregates do not collapse, nor do the clays deflocculate. Some of the problems associated with the collapse of wet aggregates and clay de-flocculation, and the formation of hard surface crusts when dry, are discussed in section 3.2.3. Pans that develop at depth in the soil profile, as a result of remolding of wet aggregates under wheel or cultivation pressure, can be barriers to root growth. Soil strength is synonymous with consistence, which is the resistance by the soil to deformation when subjected to a compressive shear force (box 2.2). Soil strength depends on the soil matrix potential m and bulk density BD, as illustrated in fig­ure 7.1. In situ soil strength is best measured using a penetrometer, as discussed in box 7.1. The soil strength at a ψm of −10 kPa (FC ) should be <2 MPa for easy root penetration and should not exceed 3 MPa at –1500 kPa (PWP). As shown in figure 7.1, when ψm is between −10 and −100 kPa, the soil strength increases with BD. The BD of vineyard soils can increase, particularly in the inter-row areas because of compaction by machinery, such as tractors, spray equip­ment, and harvesters. Typically, compaction occurs at depths between 20 and 25 cm and is more severe in sandy soils than in clay loams and clays (except when the clays are sodic; see section 7.2.3). Figure 7.2 shows the marked difference in soil compaction, measured by penetration resistance, under a wheel track and un­der a vine row on a sandy soil in a vineyard.
Legacies of War
Authors: Wilshire Howard G. , Hazlett Richard W. , Nielson Jane E.
Published: November 2020

Since 1900, United States troops have fought in more foreign conflicts than any other nation on Earth. Most Americans supported those actions, believing that they would keep the scourge of war far from our homes. But the strategy seems to have failed—it certainly did not prevent terror attacks against the U.S. mainland. The savage Oklahoma City bombing in 1995 and the 11 September 2001 (9/11) attacks on New York and Washington, D.C. were not the first to inflict war damage in America’s 48 contiguous states, however—nor were they the first warlike actions to harm innocent citizens since the Civil War. Paradoxically, making war abroad has always required practicing warfare in our own back yards. Today’s large, mechanized military training exercises have degraded U.S. soils, water supplies, and wildlife habitats in the same ways that the real wars affected war-torn lands far away. The saddest fact of all is that the deadly components of some weapons in the U.S. arsenal never found use in foreign wars but have attacked U.S. citizens in their own homes and communities. The relatively egalitarian universal service of World War II left a whole generation of Americans with nostalgia and reverence for military service. Many of us, perhaps the majority, might argue that human and environmental sacrifices are the price we must be willing to pay to protect our interests and future security. A current political philosophy proposes that the United States must even start foreign wars to protect Americans and their homes. But Americans are not fully aware of all the past sacrifices—and what we don’t know can hurt us. Even decades-old impacts from military training still degrade land and contaminate air and water, particularly in the arid western states, and will continue to do so far into the future. Exploded and unexploded bombs, mines, and shells (“ordnance,” in military terms) and haphazard disposal sites still litter former training lands in western states. And large portions of the western United States remain playgrounds for war games, subject to large-scale, highly mechanized military operations for maintaining combat readiness and projecting American power abroad.
The Global Nexus of Drug Cultivation
Authors: Hobbs Joseph J.
Published: November 2020

It is a pleasure to write the closing chapter for this volume. My tasks are to present some common themes in these diverse studies, point out the unique features, and reflect on our roles as researchers of plant-based drugs and the people who produce, distribute, and use them. The research behind this volume is extraordinary. Doing fieldwork about drugs is risky. Almost every situation described here involves illicit activities. Growers, traffickers, and merchants of these substances have every reason to be suspicious about the researcher, and they have been both generous and trusting in revealing their worlds to us. In turn we hope that our interpretations will benefit these people, not by condoning what is illegal, but by offering enlightened counsel to decision makers who should act with the best information on the human dimensions and costs of their policies, thereby reducing some of the harm done by actions based on ignorance or incomplete information. Regardless of whether or not we approve of what they do, we must marvel at the extraordinary resourcefulness of these people, particularly the peasant farmers at the base of the drug enterprise. As Steinberg (chapter 6) notes, these seemingly conservative people are amazingly flexible and adaptable to the changing world around them. And one cannot help but admire the fortitude in their labors. Westermeyer (chapter 3) describes the work of Laotian opium harvesters as “pressured, repetitive, prolonged, and grueling. Thousands of bulbs rapidly incised and scraped, incised and scraped every day, day after day, from twilight to dusk—sometimes even at night by torch—for weeks.” Their efforts are typical. This is a volume about indigenous peoples and drugs, and it is much more. It offers insight into the drugs themselves, their production and marketing, their unique place in the process of globalization, the physiological impact of their use, their spiritual and perceptual dimensions, their impact on landscapes, and their role in social and political change, as well as the drug war and alternatives to conventional drug warfare. These studies represent work that, as Mathewson (chapter 1) has written, is “immense, compelling, and critically important.”
“Lesser Breeds”
Authors: Keller Morton , Keller Phyllis
Published: November 2020

When Conant became president, Harvard College students were male, almost all white, primarily Unitarian, Congregationalist, or Episcopalian in religion, predominantly from New England. Brahmin Harvard sought to restrict the number of Jewish students and faculty; indeed, that issue often was the outlet for opposition to the effort to make Harvard a more meritocratic university. Even more pervasive was the desire to shield Harvard men and Radcliffe women from the perils of coeducation. Catholics were scant, but for different reasons: hostility to godless Harvard in Catholic churches and schools kept their numbers small during the 1920s and 1930s. As for African Americans, there were so few that it was safe to accept (if not to welcome) them—if they met academic standards for admission and had the money to pay for their education. Under Eliot’s benign lead, turn-of-the-century Harvard was more receptive to Jewish students than were other Eastern universities. Undergraduates from well-off German-Jewish families combined with a growing number of commuters from the Boston area to become a substantial presence. By the early 1920s, an estimated 20 to 25 percent of the undergraduate student body was Jewish. This was cause for concern by alumni, faculty, and not least President Lowell. In 1922 he proposed a formal Jewish quota of 12 percent. This was the limiting device traditionally used in European universities, now much in the American public mind because of the movement for quota-based immigration restriction laws. Harvard historian Samuel Eliot Morison, looking back on the controversy fifty years later, ascribed the emotional strength of the Jewish reaction to the fact that Lowell’s 12 percent quota was the same as the numerus clausus of the Russian imperial universities. Lowell’s biography, published in 1948, rather laboriously tried to exonerate him: “the poor, hard-working student, native-born or immigrant, Gentile or Jew, white or black, never had a warmer friend, although many excellent persons criticized at times his way of showing friendship.” But it is clear that Lowell shared in full measure the prejudices of his caste. Jews, he thought, lowered the moral tone of the College.
I’m Not Crazy!
Authors: Wallace Daniel J. , Brock Wallace Janice
Published: November 2020

“You look fine, and I can’t find anything wrong with you. Maybe you’re just depressed or stressed out.” Nearly all of my patients have heard this before. And they start to wonder: Am I really crazy? How could it all be in my mind? This chapter will summarize the small number of behavioral surveys that rheumatologists and psychiatrists have performed on fibromyalgia patients. The treatment of fibromyalgia will be reviewed in Parts VI and VII. Why are there so few studies that we can rely upon? First, most research is conducted at university medical centers, where fibromyalgia patients tend to be more symptomatic and have not responded to interventions by community physicians. Second, depression itself is associated with high rates of musculoskeletal pain. Also, few people have had comprehensive psychological evaluations before they became ill that can be used for comparison. Finally, instruments of psychological assessment were devised before we knew what fibromyalgia was, and popular tests such as the Minnesota Multiphasic Personality Inventory (MMPI) cannot distinguish between pain from a disease and pain from depression. Is fibromyalgia a manifestation of depression or the reverse? Well-designed studies have addressed this issue, but many used different methods, populations, ethnic groupings, referral sources, and geographical distributions. In any case, the results were reasonably similar. On average, these studies showed that about 18 percent of fibromyalgia patients have evidence of a major depression at any office visit and 58 percent have a history of major depression in their lifetime. What does this mean? At any point in time, the overwhelming majority of fibromyalgia patients are not seriously depressed. And if they are depressed, it’s usually because they do not feel well. This condition is called reactive depression and is reversible with treatment, as opposed to endogenous depression, which is caused by chemical imbalances and is much harder to treat. A well-designed study of depressed patients demonstrated that fewer than 10 percent had two or more tender points. Certain life events or historical factors are statistically present more often in fibromyalgia patients than in those without the disorder.
How to Overcome Fibromyalgia
Authors: Wallace Daniel J. , Brock Wallace Janice
Published: November 2020

When our patients are diagnosed with fibromyalgia, their initial reaction generally is “What?” At this point, we provide them with literature from fibromyalgia support groups and the Arthritis Foundation and explain what this condition means. Often we meet with family members to reinforce the educational process. In mild cases, this creates a sense of relief. Some patients who have seen several physicians and been given various diagnoses have differing reactions: “Are you just trying to put me off?” “My last rheumatologist said the same thing, told me he could do nothing for it, and sent me back to my family doctor.” “Are you sure it’s not lupus or Lyme disease or cancer?” Once our patients have accepted the diagnosis and read about the syndrome, we examine their behavior patterns and try to find ways to help them deal with the diagnosis in a constructive manner. This chapter reviews some of the emotional reactions our patients display and problems they have to deal with, gives practical advice on how to surmount obstacles, and describes community resources that help patients overcome the syndrome. It’s hard enough to get through the day when feeling unwell. In fibromyalgia, the sense of being unwell is manifested by fatigue, pain, spasm, poor sleeping, lack of stamina or endurance, and sometimes difficulty concentrating or focusing. Fibromyalgia patients frequently react to these sensations with specific attitudes, emotions, and other behavioral responses, including anxiety, anger, guilt, loss of self-esteem, depression, and fear. There are no physical markers of fibromyalgia that reveal the syndrome to others. Fibromyalgia patients have no deformities, don’t have an X marked on their fore head, look healthy, and seem able to be active. While this is good for the patient in one sense, friends, employers, and loved ones often have difficulty believing that they have so many complaints. Therefore, it’s important to be open and frank with those who care. You need to have their trust to help them understand the limitations imposed by fibromyalgia. Patients do not need to be coddled or treated like invalids; they crave and need understanding and respect.
Writing
Authors: Ehrenfeld David
Published: November 2020

The semester is over, my grade rosters have been handed to the registrar, and I am home, writing sporadically and glancing through a book by P. G. Wodehouse, whose incomparable prose, as elegant as it is funny, is always very soothing. The thirty students in Conservation Ecology were very good this year. Most of them were informed, outdoors-loving, committed, hard working people who cared for each other and seemed to enjoy the class. With a few exceptions, however, they can’t write English, and I am still recovering from the effects of reading the term papers upon which their grades were largely based. For twenty-five years, I have been assigning a major term paper in lieu (“in loo,” as one student wrote) of an exam. I used to get eighteen- to forty-page papers, acceptably or even nicely written; now the students struggle to reach fourteen pages with the help of triple spacing, margins you could drive a bus along, and type sizes usually reserved for the visually disabled. And the writing! The first mistake the students are making is to use the “spell-checkers” of their computer software as a substitute for proofreading. The results are papers in which all the words are spelled correctly, even if they are not the right words. Reading these spell-checked papers can be like trying to translate from Spanish to English based on the assumption that words that are spelled the same in the two languages have the same meaning. (This can lead to some confusion if, for example, the Spanish words are sin, cabal, or saber.) In one of the papers, I had to erase a long, marginal comment I had written when I realized that illicit was meant to be elicit. In another, I had trouble with the philosophical implications of the word modal, used throughout the text, until I turned it into model, which made more sense. Then there were words such as begum (“a Muslim lady of high rank,” my dictionary told me), which didn’t seem to fit easily into the context of a paper on the genetics of coyotes, and which didn’t have an obvious substitute.
Scientific Discoveries and Nature’s Mysteries
Authors: Ehrenfeld David
Published: November 2020

One of the joys of science is its steady production of wonderful discoveries. At irregular but not intolerable intervals, it throws out to the waiting world findings that add spice to a thousand morning newspapers and enliven the conversations of countless barbers and taxi drivers. Some branches of science are especially fruitful in their production of wonders: physics doles out an inexhaustible supply of elemental particles with clever, memorable names like quark. Medicine provides powerful antibiotics freshly isolated from weird sources such as exotic muds and frogskin, arraying them against an equally fresh crop of antibiotic-resistant microbes. Geology reveals previously unsuspected earthquake faults under major cities and dazzles us with hidden, underwater chains of volcanoes in secret, violent eruption. Even paleontology can be counted on for the latest, well-documented theory of how birds came to fly or, as I have already discussed, why the dinosaurs became extinct. And then, every ten years or so, like the return of a speeded-up Halley’s Comet, animal behavior brightens the scientific horizon with a new and incredible explanation of how animals find their way home. Not long ago, the wires were humming, or would have hummed if wires hummed anymore, with the discovery by P. Berthold and three colleagues that bird migration has a rapidly evolving genetic basis. Evidently, the inherited tendency of a population to choose a particular migratory direction can change in a few years, with the selection of another direction. Berthold, working in Radolfzell, in southwest Germany, made the most of an earlier observation: since the 1950s, increasing numbers of blackcaps, Old World warblers, have been spending the winter in Britain, traveling from their breeding grounds in Germany and Austriaduring the fall migration. Traditional wintering grounds are in the western Mediterranean countries far to the south; most blackcaps still go there in the fall. But the blackcaps wintering in Britain have done well; global warming (or chance) has ameliorated the winter climate, and the British are dedicated bird feeders. What Berthold did was to capture forty male and female blackcaps in England, transport them to Germany, breed them, and raise their young.
The Great Wilderness Debate, Again
Authors: Orr David W.
Published: November 2020

It is odd that attacks on the idea of wilderness have multiplied as the thing itself has all but vanished. Even alert sadists will at some point stop beating a dead horse. In the lower 48 states, federally designated wilderness accounts for only 1.8 percent of the total land area. Including Alaskan wilderness, the total is only 4.6 percent. This is less than the land we’ve paved over for highways and parking lots. For perspective, Disney World is larger than one-third of our wilderness areas (Turner 1998, 619). Outside the United States there is little or no protection for the 11 percent of the earth that remains wild. It is to be expected that attacks on the last remaining wild areas would come from those with one predatory interest or another, but it is disconcerting that in the final minutes of the 11th hour they come from those who count themselves as environmentalists. Each of these critics claims to be for wilderness, but against the idea of wilderness. This fault line deserves careful scrutiny. In a recent article, for example, novelist Marilynne Robinson concludes that “we must surrender the idea of wilderness, accept the fact that the consequences of human presence in the world are universal and ineluctable, and invest our care and hope in civilization” (1998, 64). She arrives at this position not with joy, but with resignation. She describes her love of her native state of Idaho as an “unnameable yearning.” But wilderness, however loved, “is where things can be hidden . . . things can be done that would be intolerable in a populous landscape.” Has Robinson not been to New York, Los Angeles, Mexico City, or Calcutta, where intolerable things are the norm? But she continues: “The very idea of wilderness permits . . . those who have isolation at their disposal [to do] as they will” (ibid.). Presumably there would be no nuclear waste sites and no weapons laboratories without wilderness in which to hide them. She ignores the fact that the decisions to desecrate rural areas are mostly made by urban people or support one urban interest or another.
Introduction
Authors: Holliday Vance T.
Published: November 2020

Soils are a potential source of much information in archaeological studies on site and feature-specific scales as well as on a regional scale. Soils are a part of the stage on which humans have evolved. As an integral component of most natural landscapes, soils also are an integral component of cultural landscapes. “Soils are active components of functioning ecosystems that reflect the spatial variability of ecological processes and at the same time have varying degrees of suitability for different kinds of human behavior” (Warren, 1982b, p. 47). Beyond physically supporting humans and their endeavors, however, soils are indicators of the nature and history of the physical and human landscape; they record the impact of human activity, they are a source of food and fuel, and they reflect the environment and record the passage of time. Soils also affect the nature of the cultural record left to archaeologists. They are a reservoir for artifacts and other traces of human activity, encasing archaeological materials and archaeological sites. Soil-forming processes also are an important component of site formation processes. Pedogenesis influences which artifacts, features, and environmental indicators (floral, faunal, and geological) are destroyed, which are preserved, and the degree of preservation. Those involved in field archaeology (as archaeologists, geoscientists, or bioscientists) routinely deal with soils—probably more so than most soil scientists or geologists (Birkeland, 1994, p. 143). However, what the soils or a soil scientist can tell archaeologists about the site and about the archaeological record is not always clear. In part, the integration of soil science in archaeology has been hampered by ambiguities in use of the term “soil” and confusion over what a soil is or is not. The bigger issue is that pedological research, particularly in the United States, has not traditionally been a component of geoarchaeology (the application of the earth science in archaeology) until recent years, in comparison with applications of other aspects of geoscience such as stratigraphy, sedimentology, or geomorphology. This situation evolved in large part because the academic study of soils typically is located in the agricultural sciences rather than the earth sciences.
Climate and Hydrologic Variations and Implications for Lake and Stream Ecological Response in the McMurdo Dry Valleys, Antarctica
Authors: Welch Kathleen A. , Lyons W. Berry
Published: November 2020

Because polar regions may amplify what would be considered small to moderate climate changes at lower latitudes, Weller (1998) proposed that the monitoring of high latitude regions should yield early evidence of global climate change. In addition to the climate changes themselves, the connections between the polar regions and the lower latitudes have recently become of great interest to meteorologists and paleoclimatologists alike. In the southern polar regions, the direct monitoring of important climatic variables has taken place only for the last few decades, largely because of their remoteness. This of course limits the extent to which polar records can be related to low latitude records, even at multiyear to decadal timescales. Climatologists and ecologists are faced with the problem that, even though these high latitude regions may provide important clues to global climatic change, the lengths of available records are relatively short. The McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) program was established in 1993. This program built on the monitoring begun in the late 1960s by researchers from New Zealand, who collected records of climate, lake level, and stream discharge in the Wright Valley, Antarctica. Griffith Taylor’s field party obtained the first data related to lake level in 1903 as part of Scott’s Discovery expedition. Analysis of the more recent data from the New Zealand Antarctic and MCM LTER programs when compared to the 1903 datum indicates that the first half of the twentieth century was a period of steadily increasing streamflows, followed in the last half of the century by streamflows that have resulted in more slowly increasing or stable lake levels (Bomblies et al. 2001). Thus, meteorological and hydrological records generated by the MCM LTER research team, when coupled with past data and the ecological information currently being obtained, provide the first detailed attempt to understand the connection between ecosystem structure and function and climatic change in this region of Antarctica. In addition, the program helps to fill an important gap in the overall understanding of climatic variability in Antarctica.
Climate Variability and Ecosystem Response at the H. J. Andrews Long-Term Ecological Research Site
Authors: Greenland David , Bierlmaier Frederick
Published: November 2020

The H. J. Andrews (AND) Long-Term Ecological Research (LTER) site represents the temperate coniferous forest of the Pacific Northwest (PNW) of the United States. The general climate of the area is highly dynamic, displaying variability at a variety of timescales ranging from daily to millennial. AND, and its surrounding region, is therefore an ideal site for examining some of the guiding questions of climate variability and ecosystem response addressed by this volume (see chapter 1). A legacy of more than 50 years of research at the site and its surrounding area ensures that several of the questions can be investigated in some depth. Here we organize our discussion within a timescale framework that is consistent with the structure of this volume. Thus, following a brief description of the general climate of the site, we discuss climate variability and ecosystem response at the daily, multidecadal, and century to millennial scale. This discussion for the PNW is supplemented in chapters 6 and 13 by a consideration of the quasi-quintennial scale and an additional ecosystem response at the decadal scale. Having described some of the climate variability and ecosystem response at the selected timescales, we will consider what this information can tell us regarding some of the guiding questions of this book. The questions that we specifically address include the following: What preexisting conditions affect the impact of the climatic event or episode? Is the climatic effect on the ecosystems direct or cascading? Does the system return to its original state? We also consider potential future climate change and its possible ecosystem effects. Located at latitude 44.2º N and longitude 122.2º W, the Andrews Forest is situated in the western Cascade Range of Oregon in the 6400-ha (15,800-acre) drainage basin of Lookout Creek, a tributary of the Blue River and the McKenzie River (figure 19.1). Elevation ranges from 410 m (1350 feet) to 1630 m (5340 feet). Broadly representative of the rugged mountainous landscape of the Pacific Northwest (PNW), the Andrews Forest contains excellent examples of the region’s conifer forests and associated wildlife and stream ecosystems. Lower elevation forests are dominated by Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), and western red cedar (Thuja plicata).
The Filesharing Movement
Authors: Goldsmith Jack , Wu Tim
Published: November 2020

Some people change history by accident, and Niklas Zennstrom counts as one of them. This soft-spoken and still largely unknown Swede, described by the Washington Post as a “younger, hipper version of Bill Gates,” started two small companies in the early 2000s that have already done much to change how people exchange information in the twenty-first century. His first company created a filesharing software application called “Kazaa” that was destined to become the most downloaded program in history. Millions of people used Kazaa to exchange billions of songs in open defiance of national copyright laws. This chapter chronicles the filesharing movement, in which Zennstrom and Kazaa played a big role. At its height this movement led many to believe that filesharing might upend the central role of national copyright law in the distribution of information. With the benefit of hindsight, we can now see that this was not to be. And so in part, this chapter is a sequel to chapters 5 and 6, showing again the importance of law and national government, even for filesharing—a technology designed to be impossible to control. This chapter also introduces a crucial new theme: the effect of technological change on the market and the legal system. Filesharing introduced a cheaper method of distributing music that sparked massive changes in the economics of music distribution and the behavior of consumers. These changes were a jolt to the copyright law system that seemed to many to render it irrelevant. What appeared a threat to copyright law, however, turned out simply to be the law’s hesitation and adjustment in the face of a massive battle between the recording industry, technological upstarts, and music consumers over the spoils of a better music distribution system made possible by the Internet. As the 1990s ended, the music recording industry’s mood was optimistic. A new and sturdy technology, the compact disc, anchored the best decade of sales ever. A handful of major labels, a textbook oligopoly, exercised near total control over the distribution of music. And while the industry faced considerable expenses in the development and marketing of new artists, existing music cost little to manufacture and could be sold for up to $20 per album. The recording industry was rich, powerful, well-connected in Congress, and uninterested in changing a successful business model.
Selective and Complete Hydrogenation of Vegetable Oils and Free Fatty Acids in Supercritical Fluids
Authors: Tacke Thomas , Panster Peter
Published: November 2020

As described in other chapters of this book and elsewhere (Jessop, 1999), a wide range of catalytic reactions can be carried out in supercritical fluids, such as Fischer–Tropsch synthesis, isomerization, hydroformylation, CO2 hydrogenation, synthesis of fine chemicals, hydrogenation of fats and oils, biocatalysis, and polymerization. In this chapter, we describe experiments aimed at addressing the potential of using supercritical carbon dioxide (and carbon dioxide/propane mixtures) for applications in the hydrogenation of vegetable oils and free fatty acids. Supercritical fluids, particularly carbon dioxide, offer a number of potential advantages for chemical processing including (1) continuously tunable density, (2) high solubilities for many solids and liquids, (3) complete miscibility with gases (e.g., hydrogen, oxygen), (4) excellent heat and mass transfer, and (5) the ease of separation of product and solvent. The low viscosity and excellent thermal and mass transport properties of supercritical fluids are particularly attractive for continuous catalytic reactions (Harrod and Moller, 1996; Hutchenson and Foster, 1995; Kiran and Levelt Sengers, 1994; Perrut and Brunner, 1994; Tacke et al., 1998). There are a number of reports on hydrogenation reactions in supercritical fluids using homogenous and heterogeneous catalysts (Baiker, 1999; Harrod and Moller, 1996; Hitzler and Poliakoff, 1997; Hitzler et al., 1998; Jessop et al., 1999; Meehan et al., 2000; van den Hark et al., 1999). We have investigated the selective hydrogenation of vegetable oils and the complete hydrogenation of free fatty acids for oleochemical applications, since there are some disadvantages associated with the current industrial process and the currently used supported nickel catalyst. The hydrogenation of fats and oils is a very old technology (Veldsink et al., 1997). It was invented in 1901, by Normann, in order to increase the melting point and the oxidation stability of fats and oils through selective hydrogenation. Since the melting point increases during the hydrogenation, the reaction is also referred to as hardening. The melting behavior of the hydrogenated product is determined by the reaction conditions (temperature, hydrogen pressure, agitation, hydrogen uptake). Vegetable oils (edible oils) are hydrogenated selectively for application in the food industry; whereas free fatty acids are completely hydrogenated for oleochemical applications (e.g., detergents).
Encrypted Genes and Their Assembly in Ciliates
Authors: Prescott David M. , Rozenberg Grzegorz
Published: November 2020

Maintenance of normal cell function and structure requires some level of stability of the cell’s DNA—at least the DNA that makes up the genes of the cell. In most eukaryotes most of the DNA in the genome does not encode genes and has no known function beyond forming long spacers between successive genes. For example, the gene density in the germline (micronuclear) genome of stichotrich ciliates (formerly referred to as hypotrich ciliates) is very low; only a few percent of the DNA encodes the approximately 27,000 different genes, and more than 95% is spacer DNA. Powerful DNA repair systems guard the stability both of nongene and gene DNA in contemporary cells, protecting it against mutagenesis. Although species survival depends on DNA stability, cell evolution requires changes in DNA. Presumably, there is a balance between instability of DNA that allows evolution and a stability that protects species from mutational extinction. Could cells evolve strategies that change the balance, allowing a greater rate of DNA change (gene evolution) without jeopardizing species survival? The stichotrichs may, in fact, have evolved such a mechanism, dramatically modifying their germline DNA during evolution to facilitate creation of new genes without reducing the level of cell survival. The modifications of germline DNA in ciliates, in turn, require dramatic DNA processing to convert germline DNA into somatic DNA during the life cycle of the organisms. The ciliate strategy rests on the evolution of nuclear dimorphism: the inclusion both of a germline nucleus (micronucleus) and a somatic nucleus (macronucleus) in the same cell (Figure 9.1; for a general review, see Prescott [6, 7]). Like the example in Figure 9.1, most stichotrich species contain two or more micronuclei and two or more macronuclei per cell. The multiple micronuclei are genetically identical to each other, and the multiple macronuclei are genetically identical; these multiplicities of nuclei have no bearing on the issues addressed in this chapter. The micronucleus is used only in cell mating, and its genes are silent. Hence, micronuclear genes do not support the maintenance, growth, or division of the cell.