bluuebunny/crossref_metadata_2025 huggingface dataset:
Iron Oxides: An Example of Structural Versatility
Authors: Jolivet Jean-Pierre
Published: November 2020

Iron is Earth’s fourth most widespread element (6.2% in mass), behind oxygen, silicon, and aluminum. It exists mostly as ferric oxide and oxyhydroxide (Fig. 7.1a) and to a lesser extent as sulfide (pyrite), carbonate (siderite), and silicate (fayalite). Iron oxides are largely used in technological areas such as metallurgy, colored pigments, magnetic materials, and catalysts. They also play an important role in the environment because the dissolution of ferric oxides in natural waters, promoted by acid–base, redox, photochemical phenomena, and also microbial mediation, allows iron to be involved in many biogeochemical processes. Iron is present in many living organisms such as plants, bacteria, mollusks, animals, and humans in various forms: . . . Porphyrinic complexes of iron, which are active centers of hemoglobin and several ferredoxins involved in biological functions, especially respiration mechanism and photosynthesis. Nanoparticles of amorphous ferric oxyhydroxides in animal and human organisms as ferritin, which allows regulation and storage of iron and in various nanophases present in plants as phytoferritin. Crystalline iron oxy(hydroxi)des produced by biomineralization processes. Goethite, lepidocrocite, and magnetite are the main constituents of radulas and the teeth of mollusks (limpets, chitons). Magnetite nanoparticles produced by magnetotactic bacteria (Fig. 7.1b), as well as by bees and pigeons, are used for purposes of orientation and guiding along the lines of force of the Earth’s magnetic field. Green rusts are also ferric- ferrous compounds belonging to the biogeochemical cycle of iron. . . . The crystal chemistry of iron oxy(hydroxi)des is very rich. The ferric, ferrous, and mixed ferric- ferrous oxygenated compounds correspond to around a dozen crystal structural types (Fig. 7.2). Most of these crystal phases can be synthesized from solutions in the laboratory, giving rise to a most diversified chemistry. They are also formed in nature because of the large variability of physicochemical conditions: an acidity range from around pH 0 to 13; redox conditions from oxic to totally anoxic media; bacterial activity that can be extremely intense; salinity largely varying from almost pure waters to real brines; presence of many organic and inorganic ligands; and various photochemical processes.
April: Six Degrees of Connectivity
Authors: Wohl Ellen
Published: November 2020

By late April, the snow is gone from the beaver meadow. The promises of March are starting to be fulfilled: insects are on the wing, some of the willows have furry catkins along their branches, and fish jump from the quiet waters of the beaver ponds. I can no longer easily get around the beaver meadows on foot unless I wear chest waders. The sound of the beaver meadow in March was primarily wind. By April, the sound is primarily moving water. The water gurgles, shushes, and whispers. In another month it will roar with the melting snows. Another three miles up the creek valley and 1,500 feet higher, one of my long-term study sites still lies under 6 feet of snow, but in the meadow I see only one patch of tenacious snow-ice in the deep shade beneath a spruce along the northern edge of the meadow. I know that snow will still fall here during late spring storms, but it will melt quickly. March felt on the cusp, as if it could as easily tip toward winter or spring. Late April is definitely spring headed toward summer. The beaver meadow remains a riverscape more brown and tan than green. The willows are still leafless, although some of the branch tips are turning pale yellow-green and others seem to be taking on a more vivid orange hue. I can see the leaf buds starting to swell. The grass has just begun to grow in dark green tips steadily forcing their way through the thick mat of last year’s dead stems. Clusters of new leaves on low-growing wintergreen are the only other sign of green outside of the channels. Some of the smaller side channels are thick with emerald green algae undulating slowly in the current. A stonefly lands on my hand. Its slender, dark gray body seems surprisingly delicate for a creature that has hatched into the vagaries of April air, with its potential for blasting winds and sudden snow squalls.
Theories of causation
Authors: Selikowitz Mark
Published: November 2020

In the definition of specific learning difficulties in the first chapter I emphasized that the delay in learning must be ‘unexplained’. It is, therefore, explicit in the definition that the cause of specific learning difficulties is presently unknown. There are few things more frustrating for a doctor to say, or for a parent to hear, than that the cause of a child’s condition is unknown. There is a natural tendency in such situations to alleviate this discomfort by guessing the cause. This is not necessarily bad, as it is by developing theories and devising experiments to test them that our knowledge advances. But the danger is that in our desire to know the cause with certainty, we may come to believe in a theory so strongly that we think of it as a fact. Theories about specific learning difficulties abound. Most are based on the assumption that there is some impairment of brain function. These theories are not mutually exclusive, since each may explain one step in the chain of events that gives rise to specific learning difficulties, as shown in Figure 3.1. Let us look at these theories one by one. These theories attempt to explain the most fundamental aspect of the condition: its primary cause. It is unlikely that a single factor can be responsible for a specific learning difficulty. Rather, it seems that a number of factors must act together. Such causation is known as ‘multifactorial’. There have been two groups of factors that have been suggested in the causation of specific learning difficulties: genetic factors and environmental factors. There is strong evidence for a genetic factor playing a role in the causation of specific learning difficulties. A number of studies have shown that children with specific learning difficulties are more likely to have a close relative with the same specific learning difficulty. No consistent pattern of inheritance has been described: sometimes it seems to be inherited from the mother, at other times from the father. For all types of such learning difficulty, boys outnumber girls by about three to one.
Arithmetic
Authors: Selikowitz Mark
Published: November 2020

Specific difficulties have been described in a number of areas of mathematics, but difficulty in arithmetic has received the most attention. This may be because all children are required to do arithmetical calculations in the early years of school, but can choose alternative subjects later, and it probably also reflects the fact that arithmetical calculations play an important part in everyday life. Another reason may be that arithmetical difficulty following brain damage in adulthood (dyscalculia) is a well-recognized and well-studied entity. This chapter will focus on specific arithmetic difficulty in children, that is, unexplained, significant delay in arithmetic ability. Although specific arithmetic difficulty was once considered rare, there is now evidence that it is not as uncommon as was previously thought. The psychologist may obtain sufficient information about the child’s arithmetical ability from the Arithmetic section (sub-test) of the Wechsler Intelligence Scale for Children (WISC-IV). This is a commonly used intelligence test that can be used for children from 6 years to 16 years 11 months. This test does not require the child to write down the answers. The problems are timed and they relate to various arithmetical skills. Addition, subtraction, multiplication, and division can all be tested. Some problems also require memorized number facts and subtle operations, such as seeing relevant relationships at a glance. The emphasis of the test is not on mathematical knowledge as such, but on mental computations and concentration. The WISC-IV will also give the psychologist information about other abilities, which may shed light on the child’s difficulties. In the Digit Span sub-test, the child’s ability to remember numbers for a short period is tested. In the Comprehension sub-test, verbal reasoning is involved. If, for example, a child has high comprehension but low arithmetic scores, this may suggest that reasoning ability is adequate in social situations, but not in situations involving numbers. If the psychologist wants further information on arithmetic ability, there are a number of tests that specifically test mathematical skills and allow these to be compared with those of other children of the same age.
Controversial treatments
Authors: Selikowitz Mark
Published: November 2020

There are no quick and easy ways of overcoming a specific learning difficulty, but conventional management, as outlined in this book, will always bring results eventually. When there is no effective cure for a condition, numerous dubious ‘cures’ arise. The existence of a number of so-called cures is usually a sign that no single one is effective. An effective treatment quickly displaces all others. Some of these treatments are a waste of time and money that could be spent more profitably in other ways to benefit the child. Some may be harmful to the physical and psychological well-being of the child. Some may have detrimental effects on the family as a whole. It is important, therefore, that you obtain reliable information from your doctor or psychologist before becoming involved in any treatment. Do not rely on stories of miraculous cures from those who promote these treatments. Evaluations should be by controlled trials published in reputable journals. Such trials should be carried out ‘blind’ whenever possible, meaning that the person who assessed the performance of children both on and off the treatment did not know which had received treatment and which had not until after the assessments were completed. If the treatment consists of a medicine, the untreated group should have received a dummy medicine (placebo) to make the comparison valid. In addition, the person who carried out the trial should not have had any vested interest in the treatment. An increasing number of independent trials of controversial treatments are now reported in scientific journals. In addition, professional and government bodies often make policy statements about certain treatments based on reviews of scientific data. If you plan to start a treatment, first be certain that you understand the risks involved. Decide upon what objective improvement you wish to see, and how long it should take before this occurs. If the objective improvement is not achieved, treatment should cease. Do not allow yourself to accept some vague qualitative improvements decided upon at a later date. Children with specific learning difficulties always develop new skills, and usually do so in sudden spurts followed by periods of consolidation.
A Brief History of Cryptography from Caesar to Bletchley Park
Authors: Singh Simon
Published: November 2020

In Julius Caesar’s Gallic Wars, he describes how he sent a message to the besieged Cicero. The messsage was encrypted by substituting Greek letters for Roman letters, then delivered in the most dramatic way imaginable. The messenger, unable to reach the camp, hurled a spear with the letter fastened to it with a thong. Although the spear lodged itself in a tower, nobody spotted it for two days. Eventually, it was taken down and delivered to Cicero, who read out the vital news to the entire camp, bringing enormous joy to his troops. This was the first documented use of a substitution cipher for military purposes. Substitution ciphers, as the name suggests, encrypt messages by replacing the original characters with different characters. This is in contrast to a transposition cipher, in which the characters remain the same, but they are transposed or rearranged to create an anagram. One of the most famous substitution ciphers is the so-called Caesar cipher, which simply replaces each letter in the message with the letter that is, say, three places further down the alphabet. Cryptographers often think in terms of the plain alphabet, the alphabet used to write the original message, and the cipher alphabet, the letters that are substituted in place of the plain letters, both of which are shown below. The plaintext is the technical name for the original message, while the ciphertext is the encrypted message. In this chapter, the plaintext is written in lower case and the ciphertext in upper case. Although this example involves a shift of 3, lesser or greater shifts are of course possible. The Caesar cipher can be generally stated as substituting each plain letter with the letter that is x places later in the alphabet, where x is between 1 and 25. This illustrates one of the basic principles of cryptography, namely the relationship between the algorithm and the key. In the Caesar cipher, the algorithm is the general idea of replacing the original letters with those that lie a fixed number of places further along the alphabet. The key, x, specifies the distance of the shift.
An ATS Girl in the Testery
Authors: Currie Helen
Published: November 2020

I joined the Auxiliary Territorial Service (ATS) in 1938 during the Munich crisis. At that time I was working as a typist in Fleet Street, and ‘Typist’ duly appeared as the classification on my enrolment papers. Being a Territorial I was called up at the very beginning of the war. Then, in 1942, I volunteered for work as a signals operator, and was sent to the signals school in Trowbridge. I was trained to locate German stations by means of their call signs and to write down (in five-letter blocks) the Morse signals being sent by the German operator. It was difficult work. I was promoted to lance corporal— richly deserved, I thought! Typists were going to be needed to operate the Tunny decoding machines, already in the process of being built. My record—typist, in the service since the outbreak of hostilities, trained in a branch of military intelligence, and with the rank of lance corporal (it was an army rule that only those with a rank could handle secret documents)—must have put me in the running. In the summer of 1942, after I had completed my signals course, I was sent to London to be interviewed by an awe-inspiring gentleman. I remember only two of the questions that he asked me. Would I like to work in the country? Could I keep a secret? I answered ‘yes’ to the first and ‘I think so’ to the second (my young life had not so far tested me greatly in this respect). Puzzled, I went back to Trowbridge. About three weeks later I was on my way to Bletchley railway station with another ATS girl, Mary. We were met there by a genial Sergeant ‘Tubby’ (I never did find out his real name). He took us to Bletchley Park, a mere 150 yards away. Major Ralph Tester was the head of the section that I now joined. He was a lovely, twinkly man and very kind. I signed the Official Secrets Act. Whatever the organisation was as a whole remained a mystery to me. It was emphasised again and again that not an iota of what I was doing should be talked about outside my section.
Desegregating the South, 1955-1970
Authors: Wilkinson J. Harvie
Published: November 2020

Southern school desegregation after Brown progressed through four successive stages. The first might be termed absolute defiance, lasting from 1955 until the collapse of Virginia’s massive resistance in 1959. The second was token compliance, stretching from 1959 until passage of the 1964 Civil Rights Act. With that act, a third phase of modest integration began with the efforts of southern school officials to avoid fund cutoffs by the Department of Health, Education, and Welfare. The 1968 Supreme Court decision of Green v. County School Board commenced a fourth phase of massive integration during which the South became the most integrated section of the country. Yet even as the fourth phase developed, a fifth—that of resegregation— was emerging in some southern localities. Breaks in history, of course, are never so neat as their chroniclers might wish. During the defiant stage, for example, North Carolina, Tennessee, Texas, and Florida practiced token compliance. And during much of the token compliance stage, Mississippi, Alabama, and South Carolina practiced total defiance. The different phases thus express only regional momentum as a whole and not the progress, or lack thereof, of a particular state. Even as a gauge of regional momentum, moreover, these phases are imperfect, given wide differences in temperament between the Deep and Upper South. These differences, particularly at first, were important. “In terms of immediate progress toward desegregation in the South,” noted Numan Bartley, “there was precious little to choose between the complex machinations of upper South states and the bellicose interposition of Virginia and the Deep South. But in terms of the future of the Brown decision, the difference was considerable. States of the upper South, with the exception of Virginia, accepted the validity of the Supreme Court decree and aimed to evade its consequences; Deep South states refused to accede any legitimacy to the decision.” Prior to the Kennedy presidency, this division “helped to keep alive the principle of Brown v. Board of Education in the South.” From 1955 to 1968 the Supreme Court remained largely inactive in school desegregation.
“Remedial” English, University
Authors: Gonzalez Laverne
Published: November 2020

Of course, statistics are meaningless except as they are translated into specific individual achievement. Whether or not the program really succeeds depends wholly on whether or not the participating students’ lives were significantly changed by this experience. That evaluation can be given only after much time has elapsed. I was in charge of training “teacher assistants” for English 100. They taught the hundreds of students enrolled each semester in the program. I have several file folders full of notes and letters I’ve received from these young teachers, many of them written after the teachers had finished working in English 100. Here’s one of those letters: . . . I walked by your English 100 class today, as your students were writing their Pre-tests. It was out of curiosity that I lingered briefly and surveyed your class, and soon my eyes fell upon you, at the “head” of the class (so unlike you, I think) writing your heart and head away—into infinity. And upon your face I saw a smile, your lips were loosely curved. I think your smile was a contented one, full of good thoughts for this semester with your students. I thought: I must have looked similarly today when I wrote as my students wrote, and I casually looked at their faces and frustrations. I must have smiled too when I thought of the unknown areas I would travel and explore with these, my students, these, as yet total strangers. I felt happy inside when I saw you sitting there writing. We were/are doing serious work in this confused world, and living life. . . . I was writing on the first day of class with those undergraduates, just as I expect the T.A.s to do. Students should see teachers writing. . . . Another T.A. wrote me: . . . I have been using “free writing” with some kids at the Community School in West Lafayette. . . . Here is poem I shared with my English 100 class. It was written in my class by an eight-year-old girl: . . .
English as a Second Language, College
Authors: Papay Twila Yates
Published: November 2020

It was January fifth of 1967, and I remember as now that I went back of my house. I cuted up some of the grass and brought it into my house. I put it under my bed. Then I went and I asked my father many question as a child of seven years old do when they are not sure about. He usually sat with us on the front porch, and told us things about the old times of his youth. As this time he explained to my brothers and I from where the tradition of the three wise king came from . . . This day was very special for me because I was the day I descovered the real truth about this famous holiday in Puerto Rico. Also, when all my dreams of childhood broke out. I remember as now that I gave my father the list of toys for the three wise king. I always had ask my father to tell the wise to bring my a set of kitchen to play with my dolls and friend. But I didn’t know that day my father was going to go and never come back home. That day I went to bed and I didn’t found anything just the old grass I had cuted out and the glass of water. I ran crying into the kitchen where my mother was cooking breakfast. I remember that I asked her why they did not brought gift to us. She said that there were many thing difficult to explain to a child like my. I was so sad that my mother called me and explain that the existence of the three wise was only a tradition and that such thing about three men coming at night and put gift under the bed were only a lie. I asked my mother who were the person who put the gift under the bed all this year. She said that she went to town bought the present and when we were slept my father and her will put it under the bed and take with them all the grass and water put it away where we couldn’t see it.
Unfinished Synthesis
Authors: Eldredge Niles
Published: November 2020

This study provides a stimulating critique of contemporary evolutionary thought, analyzing the Modern Synthesis first developed by Theodosius Dobzhansky, Ernst Mayr, and George Gaylord Simpson. The author argues that although only genes and organisms are taken as historic "individuals" in conventional theory, species, higher taxa, and ecological entities such as populations and communities should also be construed as individuals--an approach that yields the ecological and genealogical hierarchies that interact to produce evolution. This clearly stated, controversial work will provoke much debate among evolutionary biologists, systematists, paleontologists, and ecologists, as well as a wide range of educated lay readers.
Medical Care After 1950
Authors: Rothstein William G.
Published: November 2020

In the years after mid-century, declining mortality rates from infectious and other diseases increased both life expectancy and the proportion of older persons in the population. These changes, the development of third-party payment systems, and new methods of treatment have led to more use of health-care services and greater demands on physicians for quality medical care. Practically all physicians have become specialists, mostly in fields other than primary care. The shortage of family physicians has led many specialists to provide primary care, for which their training has not prepared them. The major demographic change in the population after mid-century has been the increased proportion of older people. Between 1950 and 1982, the population of the United States increased from 152.2 million to 232.1 million. The proportion of the population ages 55 and over increased from 17.0 percent in 1950 to 21.1 percent in 1982, with those 65 years of age and older increasing from 12.4 million to 26.8 million, and those ages 55 to 64 increasing from 13.4 million to 22.1 million. The number under 5 years of age, by comparison, increased by only 1 million, from 16.4 million to 17.4 million. The greater proportion of the elderly in the population has resulted from lower mortality rates and increased life expectancy. The nation’s crude death rate declined from 9.6 per 1,000 population in 1950 to 8.6 per 1,000 population in 1982, even with a larger proportion of older people. The death rate for those under 1 year of age declined the most over the period, from 33.0 per thousand to 11.4 per thousand. This produced an increase in life expectancy at birth from 68.2 years in 1950 to 74.1 years in 1982. The life expectancy of those 65 years of age increased from 13.9 to 16.8 years over the same period. Lower mortality rates from infectious diseases were responsible for much of the overall decline in mortality rates. For example, the age-adjusted death rates from tuberculosis and the combination of influenza and pneumonia, the two most serious infectious diseases at mid-century, declined from 21.7 and 26.2 per 100,000, respectively, in 1950, to 1.0 and 11.3 per 100,000, respectively, in 1982.
The Diverted Dream
Authors: Brint Steven , Karabel Jerome
Published: November 2020

In the twentieth century, Americans have increasingly looked to the schools--and, in particular, to the nation's colleges and universities--as guardians of the cherished national ideal of equality of opportunity. With the best jobs increasingly monopolized by those with higher education, the opportunity to attend college has become an integral part of the American dream of upward mobility. The two-year college--which now enrolls more than four million students in over 900 institutions--is a central expression of this dream, and its invention at the turn of the century constituted one of the great innovations in the history of American education. By offering students of limited means the opportunity to start higher education at home and to later transfer to a four-year institution, the two-year school provided a major new pathway to a college diploma--and to the nation's growing professional and managerial classes. But in the past two decades, the community college has undergone a profound change, shifting its emphasis from liberal-arts transfer courses to terminal vocational programs. Drawing on developments nationwide as well as in the specific case of Massachusetts, Steven Brint and Jerome Karabel offer a history of community colleges in America, explaining why this shift has occurred after years of student resistance and examining its implications for upward mobility. As the authors argue in this exhaustively researched and pioneering study, the junior college has always faced the contradictory task of extending a college education to the hitherto excluded, while diverting the majority of them from the nation's four-year colleges and universities. Very early on, two-year college administrators perceived vocational training for "semi-professional" work as their and their students' most secure long-term niche in the educational hierarchy. With two thirds of all community college students enrolled in vocational programs, the authors contend that the dream of education as a route to upward mobility, as well as the ideal of equal educational opportunity for all, are seriously threatened. With the growing public debate about the state of American higher education and with more than half of all first-time degree-credit students now enrolled in community colleges, a full-scale, historically grounded examination of their place in American life is long overdue. This landmark study provides such an examination, and in so doing, casts critical light on what is distinctive not only about American education, but American society itself.
Community Colleges and the American Social Order
Authors: Brint Steven , Karabel Jerome
Published: November 2020

From the earliest days of the Republic, Americans have possessed an abiding faith that theirs is a land of opportunity. For unlike the class-bound societies of Europe, America was seen as a place of limitless opportunities, a place where hard work and ability would receive their just reward. From Thomas Jefferson’s “natural aristocracy of talent” to Ronald Reagan’s “opportunity society,” the belief that America was—and should remain—a land where individuals of ambition and talent could rise as far as their capacities would take them has been central to the national identity. Abraham Lincoln expressed this deeply rooted national commitment to equality of opportunity succinctly when, in a special message to Congress shortly after the onset of the Civil War, he described as a “leading object of the government for whose existence we contend” to “afford all an unfettered start, and a fair chance in the race of life.” Throughout much of the nineteenth century, the belief that the United States was a nation blessed with unique opportunities for individual advancement was widespread among Americans and Europeans alike. The cornerstone of this belief was a relatively wide distribution of property (generally limited, to be sure, to adult white males) and apparently abundant opportunities in commerce and agriculture to accumulate more. But with the rise of mammoth corporations and the closing of the frontier in the decades after the Civil War, the fate of the “selfmade man”—that heroic figure who, though of modest origins, triumphed in the competitive marketplace through sheer skill and determination—came to be questioned. In particular, the fundamental changes then occurring in the American economy—the growth of huge industrial enterprises, the concentration of property less workers in the nation’s cities, and the emergence of monopolies—made the image of the hardworking stockboy who rose to the top seem more and more like a relic of a vanished era. The unprecedented spate of success books that appeared between 1880 and 1885 (books bearing such titles as The Law of Success, The Art of Money Getting, The Royal Road to Wealth, and The Secret of Success in Life) provide eloquent, if indirect, testimony to the depth of the ideological crisis then facing the nation.
Environmental Influences on Biomineralization
Authors: Lowenstam Heinz A. , Weiner Stephen
Published: November 2020

For the most part, the minerals that organisms form do not form abiologically in the environment in which the organism lives. In fact, some of them do not form abiologically anywhere in the biosphere. A striking example is the crystalline strontium sulfate test of the Acantharia, a group of planktonic proctoctists that is found in most of the world’s oceans. Seawater is undersaturated with respect to strontium sulfate. Thus, the biological environment of mineral formation is isolated from the surroundings. This is, in fact, a generally observed phenomenon (Chapter 3) and it is, therefore, surprising to find that in a wide variety of organisms, the environment does still in some ways influence these biogenic minerals. This can manifest itself in the particular mineral deposited (for example, the deposition of the calcium carbonate polymorph calcite as opposed to aragonite or vice versa), the concentration of minor and trace elements, the stable isotopic composition of the mineral, and, at the ultrastructural level of the tissue, the distribution of growth lines. The degree to which the environment can affect biomineralization is a function of how isolated the process is from the outside world. Poorly controlled mineralization processes are expected to be affected more than well-controlled processes, although as we show in this chapter each case must be examined individually. There are examples of a clear environmental effect occurring in one species of a particular genus, whereas another species or even subspecies of the same genus appears to be unaffected (Lowenstam 1954c). The environmental effect can and very often is filtered out by the physiological processes of the organism, which either completely or partially determine the solution characteristics of the microenvironment in which the crystals grow. A lack of appreciation of this fact has caused considerable confusion in the literature, with some investigators concluding that an environmental influence on biogenic minerals does not exist in a whole taxonomic group, because they found that it was absent in one or a number of species (Bornhold and Milliman 1973; Taylor et al. 1969). The first published documentation of this phenomenon (Lowenstam 1954a) clearly showed that closely related organisms can differ in this respect and that extrapolations and sweeping conclusions are not justified.
Evolution of Biomineralization
Authors: Lowenstam Heinz A. , Weiner Stephen
Published: November 2020

Biomineralization among living organisms is widespread, occurring in both prokaryotes and eukaryotes. It is diverse with some 60 or so minerals known to be formed by organisms under a wide variety of conditions. They are deposited at many different locations both inside and outside cells. Biomineralization occurs on such an enormous scale that it influences processes in the biosphere itself. It is, therefore, of interest to determine how this all came about—the evolution of biomineralization. The evolutionary history of biomineralization is a fascinating subject in its own right, which is the primary reason for including it in this book. However, a well-substantiated understanding of this subject is also of crucial importance to the interpretation of many aspects of research into the mechanisms of biomineralization in living organisms. An example is the observation by Veis et al. (1986) that antibodies raised against the rat incisor acidic proteins, phosphophoryns, crossreact with proteins extracted from a sea urchin test. The proteins presumably share some similar molecular structures. Did they inherit them from a common ancestor or did they evolve independently from each other to fulfill similar functions? This type of question can be asked about many comparative studies in biomineralization between phyla or even within lower taxa of the same phyla. As long as we do not have answers to these questions, the powerful tool of comparative biology in biomineralization is compromised. Studying the evolution of biomineralization has one enormous advantage over many other topics in evolutionary biology; the very material that we are interested in has the best chance of surviving the vagaries of time and being preserved in the fossil record. The fossil record at least during the last 600 million years or so is, for the most part, a documentation of remnants of the history of mineralized hard part formation by organisms. Thus, the evolution of biomineralization is one topic that can, and that should be based on the direct documentation of the fossil record. This is the way it is presented in this chapter. The corollary of this statement is also worth considering. The fossil record should be interpreted bearing in mind the evolution of biomineralization.
Theory of Radiative Transfer
Authors: Goody R. M. , Yung Y. L.
Published: November 2020

In common with astrophysical usage the word intensity will denote specific intensity of radiation, i.e., the flux of energy in a given direction per second per unit frequency (or wavelength) range per unit solid angle per unit area perpendicular to the given direction. In Fig. 2.1 the point P is surrounded by a small element of area dπs, perpendicular to the direction of the unit vector s. From each point on dπs a cone of solid angle dωs is drawn about the s vector. The bundle of rays, originating on dπs, and contained within dωs, transports in time dt and in the frequency range v to v + dv, the energy . . . Ev = Iv(P,S) dπs dωs dv dt, (2.1). . . where Iv(P, s) is the specific intensity at the point P in the s-direction. If Iv is not a function of direction the intensity field is said to be isotropic ; if Iv is not a function of position the field is said to be homogeneous.
Canons and Contexts
Authors: Lauter Paul
Published: November 2020

This collection of essays places issues central to literary study, particularly the question of the canon, in the context of institutional practices in American colleges and universities. Lauter addresses such crucial concerns as what students should read and study, how standards of "quality" are defined and changed, the limits of theoretical discourse, and the ways race, gender, and class shape not only teaching, curricula, and research priorities, but collegiate personnel actions as well. The book examines critically the variety of recent proposals for "reforming" higher education, and it calls into question many practices, like employing large numbers of part-timers, now popular with college managers. Offering concrete examples of a "comparative" method for teaching literary texts, and specific instances about "integrating" curricula, Canons and Contexts proposes realistic ideas for creating varied, spirited, and democratic classrooms and colleges.
Nature of chemical bonds for oxygen in its compounds
Authors: Sawyer Donald T. , Williams R. J. P.
Published: November 2020

The bonding for oxygen atoms in heteratomic molecules is viewed as essentially covalent [e.g., MeOH, Me2C=O, MeCH(O), and MeC(O)OOH] and similar to that for carbon, nitrogen, and chlorine atoms. In contrast, a Lewis acid-base formalism often is used for metal-oxygen compounds with ionic interactions by dianionic oxo groups (e.g., [Ba2+O2-], [Fe6+(O2)4]2- , [Mn7+(O2-)4]-, and [(Cu+)2O2-]).
Reactivity of Oxygen Radicals [HO•, RO•, HOO•, ROO-, and RC(O)O•]
Authors: Sawyer Donald T. , Williams R. J. P.
Published: November 2020

Oxygen radicals are defined as those molecules that contain an oxygen atom with an unpaired, nonbonding electron (e.g., HO·). Although triplet dioxygen (·O2·) and superoxide ion (O2 - ·) come under this definition, their nonradical chemistry dominates their reactivity, which is discussed in Chapters 6 (·O2·) and 7 (O2-·). The hydroxyl radical (HO·) is the most reactive member of the family of oxygen radicals [HO·, RO·, ·O·, HOO·, ROO·, and RC(O)O·], and is the focus of most oxygen radical research. In the gas phase the dramatic example of oxygen radical reactivity with hydrocarbon substrates is combustion, which is initiated by HO· (or RO· or MO·) and propagated by ·O2· and ·O·.
Wood and Water
Authors: Gordon Robert B. , Malone Patrick M.
Published: November 2020

The early Spanish adventurers came to America primarily to mine precious metals. Some colonists in eastern North America also had hopes of finding gold and silver, but more turned to the abundant timber and water resources of the New World and undertook lumbering and ironmaking to produce goods for export to the mother country. Through the next 200 years, most American industrial entrepreneurs used energy from wood and from flowing water. Water was a renewable resource, while wood was so abundant that new sources were easily found when a local supply was depleted. The years in which wood had a dominant place in American technology have been described by historian Brooke Hindle as “America’s Wooden Age”; on much of the continent, metal was used only where wood would not serve, as in nails, gun barrels, and cooking pots. Iron was the only metal made in significant quantities in North America during the Wooden Age. Settlers along the American coast reached the roadless interior by ascending the numerous rivers and, until well into the nineteenth century, preferred to move heavy or bulky cargoes by boat or raft. They used the flow and drop of water in streams as their principal source of mechanical power for industry, and only after 1870 did Americans generate more power with steam engines than with waterwheels.” Visitors to Old Sturbridge Village, a living-history museum in Massachusetts that re-creates community life in the early years of the nineteenth century, find wooden buildings, tools made of wood and iron, the smell of wood smoke, and machinery powered by waterwheels. Along the east coast, wood, water in lakes and streams, and iron ore were abundant but had to be used near where they were found until entrepreneurs with access to capital and technological expertise built canals, railways, and, later, electrical power-transmission systems. A craftsman who started a shop with human-powered machinery in town and subsequently wanted to use water power often had to move to a rural site. As more people did this, they spread manufacturing over the landscape or the Northeast.
Nomic Probability and the Foundations of Induction
Authors: Pollock John L.
Published: November 2020

In this book Pollock deals with the subject of probabilistic reasoning, making general philosophical sense of objective probabilities and exploring their relationship to the problem of induction. He argues that probability is fundamental not only to physical science, but to induction, epistemology, the philosophy of science and much of the reasoning relevant to artificial intelligence. Pollock's main claim is that the fundamental notion of probability is nomic--that is, it involves the notion of natural law, valid across possible worlds. The various epistemic and statistical conceptions of probability, he demonstrates, are derived from this nomic notion. He goes on to provide a theory of statistical induction, an account of computational principles allowing some probabilities to be derived from others, an account of acceptance rules, and a theory of direct inference.
Managing the Project
Authors: Kim Steven
Published: November 2020

How does one approach a large, difficult problem? By definition the solution to the problem is ill-defined, and the path to the solution is even more obscure. The poor definition of the problem does not, however, imply the complete lack of operational strategies. It is not sufficient to throw up our hands in despair and go fishing to await divine inspiration. The resolution of difficult problems—and of easy ones—can be facilitated by a coherent strategy. This “rational” nature of problem solving applies to the realm of scientific discovery: . . . However romantic and heroic we find the moment of discovery, we cannot believe either that the events leading up to that moment are entirely random and chaotic. . . . We believe that finding order in the world must itself be a process impregnated with purpose and reason. We believe that the process of discovery can be described and modeled, and that there are better and worse routes to discovery—more and less efficient paths. . . . Purposive activity enhances creative problem solving not only in science, but in nontechnical arenas as well. This chapter discusses a number of strategic issues and techniques for addressing challenging problems. Some failures are productive while others are not. An active failure is one that serves to advance the state of knowledge. Such a result may be used to modify a tentative hypothesis, whether through refinement or outright rejection. Active failures may in turn be classified into two types: definitive or mixed. A definitive failure is a strong result that may be used to overturn a proposition by showing it to be false. To illustrate, consider the question, “Are there stars in our galaxy that are over 15 billion years old?” Suppose that a means were found to give a definitive answer, and the resulting answer was “No.” This type of failure is actually a positive result for the opposite hypothesis. In other words, the negative response is actually a positive confirmation of the query, “Are there no stars in our galaxy over 15 billion years old?” In fact, a statistician might well have begun the investigation with the null hypothesis, “No star in our galaxy is over 15 billion years old.”
Vowel Omissions
Authors: Treiman Rebecca
Published: November 2020

In this chapter and the following one, I turn to omission errors. These are errors in which children fail to represent a phoneme in their spelling. I ask which phonemes children tend to omit and why. This chapter focuses on omissions of vowels, while Chapter 8 considers omission errors on consonants. Also included in Chapter 8 is a comparison of vowel omission errors and consonant omission errors. The study of vowel omissions takes on particular importance in light of the claim that beginning spellers are particularly likely to omit vowels (Ehri, 1986; Morris & Perney, 1984). For example, Morris and Perney (1984) state that semiphonetic spellers often produce spellings like M or ML for mail, omitting the middle vowels of one-syllable words. Not until the phonetic stage, they say, do vowels begin to appear in children’s spellings of such words. Do children omit the vowel of mail because the phoneme is in the middle of the word or do they omit it specifically because it is a vowel? To find out, it is necessary to examine words whose phonemic structure is more complex than consonant-vowel-consonant. Only then will we be able to determine whether all phonemes in the middles of words are susceptible to omission, or just vowels. Consider the child who spelled rainy as RNIE. The spoken form of this word contains four phonemes—/r/, /e/, /n/, and /i/. The child who produced RNIE symbolized /r/ with r, /n/ with n, and /i/ with ie. The child failed to represent /e/ altogether, a vowel omission error. Other spellings that contain vowel omissions are HLP for help, in which /ɛ/ is deleted, and BLUN for balloon, in which the unstressed /ə/ of the first syllable is deleted. In this study, omission errors are defined by reference to the spoken form of the word, not by reference to its conventional spelling. Thus, the child who spelled said as SID is not considered to have made an omission error. This child did symbolize the vowel, albeit with i instead of with the correct ai.
Inflected and Derived Words
Authors: Treiman Rebecca
Published: November 2020

In this chapter, I discuss the first graders’ spellings of inflected and derived words. The children in this study often misspelled inflected words (Chapter 2). One type of error that has already been documented is the omission of inflectional endings like the /s/ of books (Chapter 8). This chapter considers the children’s spellings of inflected and derived words in more detail. Before beginning the discussion, some definitions and examples are in order. In English, inflections are added to the ends of words to mark such things as tense and number. For example, helped contains the verb stem help plus the past tense inflectional suffix. I refer to the past tense suffix as -D. Helped contains two morphemes or units of meaning, help and -D. The inflected word books also contains two morphemes, the stem book and the plural suffix -Z. As these examples show, the addition of an inflectional suffix does not change a word’s part of speech. Derivations differ in several ways from inflections. For one thing, English derivational morphemes may be either prefixes or suffixes. One derivational prefix is re-, which may be added to the verb read to form reread. Derivational suffixes include -ion and -ly. Unlike inflections, derivations may change a word’s part of speech. For example, the noun vacation is derived from the verb vacate by the addition of-ion; the adjective facial is derived from the noun face by the addition of -ial. The relation in meaning between a stem and a derived form is often less transparent than the relation in meaning between a stem and an inflected form. For instance, one cannot predict the full meaning of vacation from the meaning of its parts. As discussed in Chapter 1, the spellings of inflected and derived words in English often represent the words’ morphemic forms rather than their phonemic forms. For example, the past tense suffix is /t/ in words like helped, whose stem ends with a voiceless consonant, but /d/ in words like cleaned, whose stem ends with a voiced consonant. The phonemic forms of stems, too, sometimes change when inflectional or derivational morphemes are added.