bluuebunny/crossref_metadata_2025 huggingface dataset:
Histones participate in base excision repair of 8-oxodGuo by transiently cross-linking with active repair intermediates in nucleosome core particles
Authors: Ren Mengtian , Shang Mengdi , Wang Huawei , Xi Zhen , Zhou Chuanzheng
Published: November 2020

8-Oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) is a biomarker of oxidative DNA damage and can be repaired by hOGG1 and APE1 via the base excision repair (BER) pathway. In this work, we studied coordinated BER of 8-oxodGuo by hOGG1 and APE1 in nucleosome core particles and found that histones transiently formed DNA-protein cross-links (DPCs) with active repair intermediates such as 3′-phospho-α,β-unsaturated aldehyde (PUA) and 5′-deoxyribosephosphate (dRP). The effects of histone participation could be beneficial or deleterious to the BER process, depending on the circumstances. In the absence of APE1, histones enhanced the AP lyase activity of hOGG1 by cross-linking with 3′-PUA. However, the formed histone-PUA DPCs hampered the subsequent repair process. In the presence of APE1, both the AP lyase activity of hOGG1 and the formation of histone-PUA DPCs were suppressed. In this case, histones could catalyse removal of the 5′-dRP by transiently cross-linking with the active intermediate. That is, histones promoted the repair by acting as 5′-dRP lyases. Our findings demonstrate that histones participate in multiple steps of 8-oxodGuo repair in nucleosome core particles, highlighting the diverse roles that histones may play during DNA repair in eukaryotic cells.
Length of Stay Beyond Medical Readiness in a Neurosurgical Patient Population and Associated Healthcare Costs
Authors: Linzey Joseph R , Foshee Rachel , Moriguchi Francine , Adapa Arjun R , Koduri Sravanthi , Kahn Elyne N , Williamson Craig A , Sheehan Kyle , Rajajee Venkatakrishna , Thompson B Gregory , Muraszko Karin M , Pandey Aditya S
Published: November 2020

BACKGROUND

Length of stay beyond medical readiness (LOS-BMR) leads to increased expenses and higher morbidity related to hospital-acquired conditions.

OBJECTIVE

To determine the proportion of admitted neurosurgical patients who have LOS-BMR and associated risk factors and costs.

METHODS

We performed a prospective, cohort analysis of all neurosurgical patients admitted to our institution over 5 mo. LOS-BMR was assessed daily by the attending neurosurgeon and neuro-intensivist with a standardized criterion. Univariate and multivariate logistic regressions were performed.

RESULTS

Of the 884 patients admitted, 229 (25.9%) had a LOS-BMR. The average LOS-BMR was 2.7 ± 3.1 d at an average daily cost of $9 148.28 ± $12 983.10, which resulted in a total cost of $2 076 659.32 over the 5-mo period. Patients with LOS-BMR were significantly more likely to be older and to have hemiplegia, dementia, liver disease, renal disease, and diabetes mellitus. Patients with a LOS-BMR were significantly more likely to be discharged to a subacute rehabilitation/skilled nursing facility (40.2% vs 4.1%) or an acute/inpatient rehabilitation facility (22.7% vs 1.7%, P < .0001). Patients with Medicare insurance were more likely to have a LOS-BMR, whereas patients with private insurance were less likely (P = .048).

CONCLUSION

The most common reason for LOS-BMR was inefficient discharge of patients to rehabilitation and nursing facilities secondary to unavailability of beds at discharge locations, insurance clearance delays, and family-related issues.
Racial/Ethnic Disparities Across Indicators of Cigarette Smoking in the Era of Increased Tobacco Control, 1992–2019
Authors: Sakuma Kari-Lyn K , Pierce John P , Fagan Pebbles , Nguyen-Grozavu France T , Leas Eric C , Messer Karen , White Martha M , Tieu Amanda S , Trinidad Dennis R
Published: November 2020

Introduction

This study compared tobacco use and cessation for African Americans (AA), Asians/Pacific Islanders (API), Hispanics/Latinos (H/L), American Indian/Alaskan Natives (AI/AN), and non-Hispanic Whites (NHW) in the United States to California (CA), the state with the longest continually funded tobacco control program. The purpose of this study was to identify tobacco use disparities across racial/ethnic groups across time.

Methods

Cigarette use prevalence (uptake and current use), consumption (mean number of cigarettes smoked per day [CPD]), and quit ratios were calculated across survey years, and trends were examined within each race/ethnic group and comparing between CA and the United States, utilizing the 1992–2019 Tobacco Use Supplements to the Current Population Survey.

Results

Prevalence decreased for all race/ethnic groups. Current use among CA NHW showed significant decline compared with US counterparts, whereas US H/L showed greater decline than CA counterparts. CPD decreased by approximately 30% across race/ethnic groups, with CA groups having lower numbers. The greatest decrease occurred among AA in CA (average 10.3 CPD [95% confidence interval (CI): 10.3, 12.6] in 1992/1993 to 3 CPD [95% CI: 2.4, 3.7] in 2018/2019). Quit ratios increased from 1992/1993 to 2018/2019 for CA H/L 52.4% (95% CI: 49.8, 53.0) to 59.3 (95% CI: 55.8, 62.5) and CA NHWs 61.5% (95% CI: 60.7, 61.9) to 63.8% (95% CI: 63.9, 66.9).

Conclusions

Although overall prevalence decreased over time for each racial/ethnic group, declines in CA outpaced the United States only for NHWs. Reductions in CPD were encouraging but the quit ratio points to the need to increase tobacco control efforts toward cessation.

Implications

The successes in reduced cigarette use uptake and prevalence across time for both California and the rest of the United States were observed largely among non-Hispanic White populations. Although reductions in the number of cigarettes smoked per day are a notable success, particularly among the Californian African Americans, efforts to support quitting across racial/ethnic groups, especially marginalized groups, need to be prioritized.
The Life Cycles of the Council on Environmental Quality and the Environmental Protection Agency
Authors: Conant James K. , Balint Peter J.
Published: November 2020

In 1970, due to increasing public concern about the environment, a dramatic series of bipartisan actions were taken to expand the national government's efforts to control pollutants. In that year, the Congress and President Nixon established two key federal agencies to address the nation's growing environmental problems: the Council on Environmental Quality (CEQ) and the Environmental Protection Agency (EPA). But despite this initial recognition of the pressing problems presented by environmental degradation, support for related policymaking and administration waxed and waned over the next thirty-five years, as other domestic and foreign policy problems rose to the top of the public and legislative agendas. What does the future hold for environmental policy in the United States, given the highly polarized politics surrounding the issue today? In this book, James K. Conant and Peter J. Balint examine what happened to the CEQ and EPA between 1970 and 2010 by using changes in leadership and budgetary resources as key indicators of the agencies' vitality and capacity for implementing pollution control laws. They also examine correlations between the agencies' fortunes and various social, political, and economic variables. The authors conclude with several scenarios about what the future holds for these important environmental agencies.
Time to Go After the Feds
Authors: Wurster Charles F.
Published: November 2020

By the fall of 1969 we knew we had to challenge pesticide regulation by the federal government if we were to ultimately prevail against DDT, but we did not know how to do it. We had the science well in hand and knew how to present it, with literally hundreds of scientists prepared to testify within their areas of expertise. We did not have the organizational structure to launch such an effort at the federal level, however, and we were certainly short of money. At about that time Joseph L. Sax, then the leading proponent of the development of environmental law at the University of Michigan Law School, suggested that we contact the newly founded Center for Law and Social Policy (CLASP), a public-interest law firm in Washington, DC. Joe was a member of the CLASP board. He insisted that DDT was in violation of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and that the U.S. Department of Agriculture (USDA) was not enforcing FIFRA. I therefore called and talked at length with James W. Moorman (Fig. 7.1), attorney for CLASP, describing the DDT problem and proposed action against USDA. “If we are going to do this, then you are going to come down here and help me put the case together,” said Jim firmly. That was not music to my ears: I had other things I needed to do, but shortly I was on my way to Washington. CLASP was in a rundown part of Washington, and my “housing” consisted of sleeping on an old mattress in their dusty attic. But we got to work and wrote a petition to USDA in about a week. The petition was a formal legal request that the FIFRA registrations for DDT be canceled. The petition also requested that USDA suspend the registrations while it was considering their cancellation. We had no illusions that USDA would grant our request, but it was Jim’s advice that we go to USDA for administrative relief before seeking cancellation and suspension from the courts.
Misadventures in Modification
Authors: Revesz Richard , Lienke Jack
Published: November 2020

Imagine a large wooden ship, in service for generations. As its planks decay, they are swapped out for new—but otherwise identical—timbers. Over time, every piece of the ship is replaced in this manner so that eventually not one of its original planks remains. Is it still the same ship? If not, when did it lose its identity? When the first plank was replaced? The last? At some point in between? This ancient brainteaser, commonly known as the Ship of Theseus (after the mythical, Minotaur-slaying king of Athens), illustrates the classic philosophical problem of “Identity Through Time.” How much can an object change before it simply becomes something else? Philosophers have been debating that question for thousands of years. And so, since 1970, have the federal regulators charged with implementing the Clean Air Act. As we explained in Chapter 3, the Clean Air Act authorized the EPA administrator to create performance standards only for “new” stationary sources of pollution. But there was a twist: the statute defined a “new source” as “any stationary source, the construction or modification of which is commenced after the publication of [an applicable New Source Performance Standard].” In other words, the Act included a mechanism—“modification”—by which a source’s identity might change from “existing” to “new.” In theory, treating modified sources as “new” could have served as a de facto limit on the duration of grandfathering, preventing old plants from permanently avoiding compliance with federal performance standards. After all, no plant could keep running forever without requiring at least some upgrades. But what sort of upgrades should qualify as a “modification” within the meaning of the Clean Air Act? For Congress and the EPA, answering this question proved every bit as difficult as determining whether it was the third, thirteenth, or thirtieth replacement plank that transformed the Ship of Theseus into a different vessel. As a result, many of the nation’s power plants have managed to enjoy seemingly indefinite immunity from New Source Performance Standards, even after undertaking comprehensive renovations. Why did Congress decide to treat modified sources differently than other existing sources?
Near Abroad
Authors: Toal Gerard
Published: November 2020

Before Russia invaded Ukraine, it invaded Georgia. Both states are part of Russia's "near abroad" - newly independent states that were once part of the Soviet Union and are now Russia's neighbors. While the Russia-Georgia war of 2008 faded from the headlines in the wake of the global recession, the geopolitical contest that created it did not. Six years later, the spectre of a revanchist Russia returned when Putin's forces invaded and annexed the Crimean peninsula, once part of Russia but an internationally recognized part of Ukraine since the Soviet collapse. Crimea's annexation and follow on conflict in eastern Ukraine have generated the greatest geopolitical crisis on the European continent since the end of the Cold War. In Near Abroad, the eminent political geographer Gerard Toal moves beyond the polemical rhetoric that surrounds Russia's interventions in Georgia and Ukraine to study the underlying territorial conflicts and geopolitical struggles. Central to understanding are legacies of the Soviet Union collapse: unresolved territorial issues, weak states and a conflicted geopolitical culture in Russia over the new territorial order. The West's desire to expand NATO contributed to a growing geopolitical contest in Russia's near abroad. This found expression in a 2008 NATO proclamation that Georgia and Ukraine will become members of NATO, a "red line" issue for Russia. The road to invasion and war in Georgia and Ukraine, thereafter, is explained in Near Abroad. Geopolitics is often thought of as a game of chess. Near Abroad provides an account of real life geopolitics, one that emphasizes changing spatial relationships, geopolitical cultures and the power of media images. Rather than being a cold game of deliberation, geopolitics is often driven by emotions and ambitions, by desires for freedom and greatness, by clashing personalities and reckless acts. Not only a penetrating analysis of Russia's relationships with its regional neighbors, Near Abroad also offers an analysis of how US geopolitical culture frequently fails to fully understand Russia and the geopolitical archipelago of dependencies in its near abroad.
A World From Dust
Authors: McFarland Ben
Published: November 2020

A World From Dust describes how a set of chemical rules combined with the principles of evolution in order to create an environment in which life as we know it could unfold. Beginning with simple mathematics, these predictable rules led to the advent of the planet itself, as well as cells, organs and organelles, ecosystems, and increasingly complex life forms. McFarland provides an accessible discussion of a geological history as well, describing how the inorganic matter on Earth underwent chemical reactions with air and water, allowing for life to emerge from the world's first rocks. He traces the history of life all the way to modern neuroscience, and shows how the bioelectric signals that make up the human brain were formed. Most popular science books on the topic present either the physics of how the universe formed, or the biology of how complex life came about; this book's approach would be novel in that it condenses in an engaging way the chemistry that links the two fields. This book is an accessible and multidisciplinary look at how life on our planet came to be, and how it continues to develop and change even today. This book includes 40 illustrations by Gala Bent, print artist and studio faculty member at Cornish College of the Arts, and Mary Anderson, medical illustrator.
The Icon Project
Authors: Sklair Leslie
Published: November 2020

In the last quarter century, a new form of iconic architecture has appeared throughout the world's major cities. Typically designed by globe-trotting "starchitects" or by a few large transnational architectural firms, these projects are almost always funded by the private sector in the service of private interests. Whereas in the past monumental architecture often had a strong public component, the urban ziggurats of today are emblems and conduits of capitalist globalization. In The Icon Project, Leslie Sklair focuses on ways in which capitalist globalization is produced and represented all over the world, especially in globalizing cities. Sklair traces how the iconic buildings of our era-elaborate shopping malls, spectacular museums, and vast urban megaprojects--constitute the triumphal "Icon Project" of contemporary global capitalism, promoting increasing inequality and hyperconsumerism. Two of the most significant strains of iconic architecture--unique icons recognized as works of art, designed by the likes of Gehry, Foster, Koolhaas, and Hadid, as well as successful, derivative icons that copy elements of the starchitects' work--speak to the centrality of hyperconsumerism within contemporary capitalism. Along with explaining how the architecture industry organizes the social production and marketing of iconic structures, he also shows how corporations increasingly dominate the built environment and promote the trend towards globalizing, consumerist cities. The Icon Project, Sklair argues, is a weapon in the struggle to solidify capitalist hegemony as well as reinforce transnational capitalist control of where we live, what we consume, and how we think.
Natural Gas : The Least Polluting Of The Fossil Fuels
Authors: McElroy Michael B.
Published: November 2020

In terms of emissions from combustion, natural gas, composed mainly of methane (CH4), is the least polluting of the fossil fuels. Per unit of energy produced, CO2 emissions from natural gas are 45.7% lower than those from coal (lignite), 27.5% lower than from diesel, and 25.6% lower than from gasoline. As discussed by Olah et al. (2006), humans have long been aware of the properties of natural gas. Gas leaking out of the ground would frequently catch fire, ignited, for example, by lightning. A leak and a subsequent fire on Mount Parnassus in Greece more than 3,000 years ago prompted the Ancient Greeks to attach mystical properties to the phenomenon— a flame than could burn for a long time without need for an external supply of fuel. They identified the location of this gas leak with the center of the Earth and Universe and built a temple to Apollo to celebrate its unique properties. The temple subsequently became the home for the Oracle of Delphi, celebrated for the prophecies inspired by the temple’s perpetual flame. The first recorded productive use of natural gas was in China, dated at approximately 500 BC. A primitive pipeline constructed using stems of bamboo was deployed to trans¬port gas from its source to a site where it could be used to boil brine to produce both economically valuable salt and potable water. Almost 2,000 years would elapse before natural gas would be tapped for productive use in the West. Gas from a well drilled near Fredonia, New York, was used to provide an energy source for street lighting in 1821. The Fredonia Gas Light Company, formed in 1858, was the first commercial entity established specifically to market natural gas. Joseph Newton Pew, founder of the Sun Oil Company (now Sunoco), established a company in 1883 to deliver natural gas to Pittsburgh, where it was used as a substitute for manufactured coal gas (known also as town gas). Pew later sold his interests in natural gas to J. D. Rockefeller’s Standard Oil. The early application of natural gas was primarily for lighting, not only for streets but also for factories and homes.
The Chemist as Philosopher: D. I. Mendeleev’s “The Unit” and “Worldview”
Authors: Gordin Michael D.
Published: November 2020

The Periodic System of chemical elements is almost certainly the most widely recognized scientific object in the world today, even though extensive debates persist about what it exactly is. Is it a theory, a collection of empirical data, a tabular arrangement of that data, a particular (best) tabular arrangement, a “paper tool,” or something else besides? Precisely because the periodic system has over close to 150 years remained so significant to the training and practice of scientists, the broader field of science studies has devoted considerable attention to it, most prominently in the philosophy of science. Among the many different approaches to articulating a philosophical foundation for the periodic system, one central strand is historicist, which places great emphasis on the individual (or individuals) to whom one attributes its discovery (Gordin 2012). Almost universally, credit for the formulation of the periodic system is assigned to St. Petersburg chemist Dmitrii Ivanovich Mendeleev (1834–1907) for his 1869 table of elements, which he later used to predict the properties of three yet-undiscovered elements. Although the philosophical justification of the periodic system by no means requires engagement with Mendeleev’s own views about the periodic system—or, as argued in Gordin (2004, 182–189), how those views changed over the course of his lifetime as periodicity became more central to chemical practice—nonetheless it remains of interest to understand precisely what Mendeleev thought he was about in constructing his system, as well as his post hoc justifications of it. There is, however, an obstacle to the full development of this line of inquiry: the Russian language itself. There is a substantial body of Imperial Russian, Soviet, and post-Soviet scholarship that would be of interest to the international community of philosophers and historians of chemistry, but it remains locked in a language not widely read by Western scholars. Even more problematic, only a very slender selection of primary sources are accessible in Western European languages (most widely cited are those available in English, although the corpus is larger if one includes French and German).
Orca
Authors: Colby Jason M.
Published: November 2020

Since the release of the documentary Blackfish in 2013, millions around the world have focused on the plight of the orca, the most profitable and controversial display animal in history. Yet, until now, no historical account has explained how we came to care about killer whales in the first place. Drawing on interviews, official records, private archives, and his own family history, Jason M. Colby tells the exhilarating and often heartbreaking story of how people came to love the ocean's greatest predator. Historically reviled as dangerous pests, killer whales were dying by the hundreds, even thousands, by the 1950s--the victims of whalers, fishermen, and even the US military. In the Pacific Northwest, fishermen shot them, scientists harpooned them, and the Canadian government mounted a machine gun to eliminate them. But that all changed in 1965, when Seattle entrepreneur Ted Griffin became the first person to swim and perform with a captive killer whale. The show proved wildly popular, and he began capturing and selling others, including Sea World's first Shamu. Over the following decade, live display transformed views of Orcinus orca. The public embraced killer whales as charismatic and friendly, while scientists enjoyed their first access to live orcas. In the Pacific Northwest, these captive encounters reshaped regional values and helped drive environmental activism, including Greenpeace's anti-whaling campaigns. Yet even as Northwesterners taught the world to love whales, they came to oppose their captivity and to fight for the freedom of a marine predator that had become a regional icon. This is the definitive history of how the feared and despised "killer" became the beloved "orca"--and what that has meant for our relationship with the ocean and its creatures.
Competition in the classroom
Authors: Bennett Peggy D.
Published: November 2020

Sometimes the best way to generate eagerness and involve­ment is to create competition. Whether it is high- stakes or playful, pitting students against one another in pedagogical set­tings can be fun. It can also be risky. At times, competition in classrooms can take a toll on learning and create more bad feelings than good. Competition may send unintended messages of superiority and inferiority to the winners and the losers. Competition may ratchet up the energy so that eagerness turns into melee and long- term educational goals are forfeited for short- term classroom engagement. When participation is expected in classroom competitions, students likely do not have the choice to opt out. Some already know they will fail in front of their peers. Some choose to be goofy or intentionally wrong rather than show their peers how “smart” or “dumb” they are. Some cannot perform under pressure: noise and frantic energy block their ability to think on the spot. Our whole lives can become a competition when we habitu­ally judge who is better or worse than we are. In classroom contests, incentives like trinkets, privileges, or bragging rights raise the ante. The “three Be’s” can provide some guidance for monitoring the influence of competition in the classroom: • Be wise about the effects of competition for academic purposes. • Be savvy about which students may be less able to access their knowledge during confrontational recall. • Be thoughtful about whether competition is contributing to or detracting from educational goals and achievements. We are all competitive by nature, and such impulse can help people achieve things they would never accom­plish otherwise . . . . Appeal sparingly to the competitive urge . . . because competition has only limited usefulness.
Getting To Know Parallelism
Authors: Dasgupta Subrata
Published: November 2020

Every morning the first thing that X does is make tea for herself. She first turns on the stove and then while the stove ring is heating up, she pours water from the faucet into the kettle. She then places the kettle on the stove ring, now nicely hot, and while the water is being heated she puts tea bags into the teapot; she then pours milk from the milk carton into a milk jug and then puts the milk jug into the microwave oven. After the water starts to boil she pours water into teapot. And while the tea “gathers strength” in the teapot, she presses the time button on the microwave to start warming the milk. After the milk is warmed she first pours tea from the teapot into a teacup and then adds milk from the warmed milk jug to the tea in the cup. This tiny, humdrum, comforting, domestic scenario X enacts every morning has many (but not all) of the ingredients of a situation that involves the scope and limits of parallel processing. More precisely, the art of making tea as practiced by X entails a blend of both sequential and parallel events. We note that certain events can take place in parallel (or concurrently) because they do not interfere with one another; for example, the heating of the stove and the pouring of water into the kettle. But other events must be sequentially ordered either because they interfere with one another or because one event must complete before the other can begin. The kettle can be placed on the stove ring only after it has been filled with water; water can be poured into the teapot only after the water has boiled. But notice also that there is some flexibility in the ordering of X’s actions. She can defer turning on the stove until after the kettle is placed on the stove ring; she can alter the ordering of pouring water into the teapot and placing teabags into the pot; she could defer warming the milk in the microwave until the tea has brewed.
Unconditional Education
Authors: Detterman Robin , Ventura Jenny , Rosenthal Lihi , Berrick Ken
Published: November 2020

After decades of reform, America's public schools continue to fail particular groups of students; the greatest opportunity gaps are faced by those whose achievement is hindered by complex stressors, including disability, trauma, poverty, and institutionalized racism. When students' needs overwhelm the neighborhood schools assigned to serve them, they are relegated to increasingly isolated educational environments. Unconditional Education (UE) offers an alternate approach that transforms schools into communities where all students can thrive. It reduces the need for more intensive and costly future remediation by pairing a holistic, multi-tiered system of supports with an intentional focus on overall culture and climate, and promotes systematic coordination and integration of funding and services by identifying gaps and eliminating redundancies to increase the efficient allocation of available resources. This book is an essential resource for mental health and educational stakeholders (i.e., school social workers, therapists, teachers, school administrators, and district-level leaders) who are interested in adopting an unconditional approach to supporting the students within their schools.
August: Legacy Effects
Authors: Wohl Ellen
Published: November 2020

Emily Dickinson wrote a lovely poem using a brook as a metaphor for one’s interior life. The poem includes the lines: . . . And later, in August it may be, When the meadows parching lie, Beware lest this little brook of life Some burning noon go dry! . . . No chance of the little brook going dry if it runs through a beaver meadow. The movement of water across and through the North St. Vrain beaver meadow has slowed perceptibly by August. Some of the secondary channels barely flow and the main channel is easily crossed on foot. The water remains high in the main beaver pond, but few of the small dams winding across the meadow have water spilling over them. My feet are less likely to sink into wet black muck as I wander through the meadow, and even the moose tracks leave less of an imprint in the drying soil. Plenty of water remains, however, and the meadow is a much brighter shade of green than the adjacent, drier hill slopes. Many flowers remain in bloom across the meadow. Stalks bristling with the elaborate, richly pink blossoms of elephant’s head rise above standing water. Dusky purple monkshood flowers in slightly drier soil, as do the showy blue and white columbines. The blue bell-shaped flowers of harebell mark the driest sites. The late-summer flowers are joined now by the spreading tan or scarlet caps of fungi, as well as green berries on the ground juniper and kinnikinnick growing on the drier terrace beside the beaver meadow. Songbirds born this summer are fully feathered and capable fliers, and some of the birds have already left the meadow for the year. Early morning temperatures carry a hint of the coming autumn. The beaver kits grow steadily more capable, too, and by now they are used to foraging on their own. Presumably, this frees the breeding adult female for more time spent in dam and lodge repair or starting the food cache for the coming winter.
Language
Authors: Selikowitz Mark
Published: November 2020

Vanessa was first seen at the clinic one year ago, at the age of eight years. Her teacher had reported that she seemed ‘slower’ than the other children in the class. She observed that Vanessa often did not understand what was going on in the class, and was easily upset by changes in routine. She also had difficulties expressing her ideas and relating her experiences. Her reading, spelling, and writing were all behind those of the rest of the class. A psychologist’s assessment showed Vanessa’s non-verbal intelligence to be in the average range, but with difficulties in comprehension. Her reading, spelling, and writing all showed more than two years’ delay. A doctor could find no abnormalities to account for her problem. Her hearing was tested and found to be normal. Vanessa was referred to a speech therapist. She found that Vanessa’s comprehension was at a level more than two years below her age and that she had many difficulties in her understanding of language. For example, although she understood common prepositions such as ‘in’, ‘on’, and ‘under’, she misinterpreted others such as ‘beside’, ‘behind’, ‘through’, and ‘around’. She also confused past and present tenses. The speech therapist spoke to the parents and the teacher about ways of helping Vanessa. She also started seeing her regularly, once a week, for speech therapy sessions. Now, after 10 months of such help, Vanessa has shown great improvement in her language comprehension and her academic skills. Language plays a central role in specific learning difficulties. Reading requires the ability to decode written language and spelling and writing require the ability to encode spoken language. Arithmetic requires language skills to understand the words used to state problems involving numbers. This chapter deals with the disorders of speech and language that often accompany specific learning difficulties. These may involve the understanding of language (which is referred to as receptive language) and the use of language (which is referred to as expressive language). There may also be involvement of speech (which relates to the clarity and fluency of the spoken word).
Attention-deficit/hyperactivity disorder and sequential organization difficulties
Authors: Selikowitz Mark
Published: November 2020

This chapter deals with two separate areas of learning: attention and sequential organization. Difficulties in either area can occur in isolation or in combination with other forms of specific learning difficulty. The ability to ignore distractions and to focus on one activity at a time is a skill that children usually develop gradually as they grow. It is quite normal for toddlers and pre-school-aged children to be easily distractible, but the ability to channel attention selectively usually increases progressively once children start school. Some children experience significant difficulties in learning to attend. As a result, they are easily distractible and do not persist for long with tasks. If this is a significant problem, it is referred to by the umbrella term ‘attention-deficit/hyperactivity disorder’ (ADHD). This means attention-deficit with or without hyperactivity. Such children may be overactive and impulsive, although this is not always the case. It is this overactivity that has given rise to the term hyperactivity (‘hyper’ is Greek for ‘over’). All children with attention-deficit/hyperactivity disorder experience difficulty with concentration. There are two forms of the condition: one where overactivity and impulsivity are present and the other where these coexisting problems are absent. The two forms of attention-deficit/hyperactivity disorder may be clarified by describing two children, each with one of the forms of the disorder. George is his mother’s third child. She describes him as completely different from the other two. As a baby he slept very little and cried constantly. As a toddler he was always on the go, ‘as if driven by a motor’. Now, aged nine years, his teacher describes him as ‘disorganized, disruptive, and fidgety’. His mother reports that he hardly ever sits still at home. He will not sit through a favourite TV programme or a meal. He is still so disorganized that if she did not help him to dress in the morning, he would not be in time for school. He is also very impulsive. He does not seem to think before he acts. He takes terrible risks and often says the first thing that comes in to his head.
Colossus
Authors: Copeland B. Jack
Published: November 2020

The American ENIAC is customarily regarded as the first electronic computer. In this fascinating volume, Jack Copeland rewrites the history of computer science, arguing that in reality Colossus--the giant computer built in Bletchley Park by the British secret service during World War II--predates ENIAC by two years. Until very recently, much about the Colossus machine was shrouded in secrecy, largely because the code-breaking algorithms employed during World War II remained in use by the British security services until a short time ago. Copeland has brought together memoirs of veterans of Bletchley Park--the top-secret headquarters of Britain's secret service--and others who draw on the wealth of declassified information to illuminate the crucial role Colossus played during World War II. A must read for anyone curious about code-breaking or World War II espionage, Colossus offers a fascinating insider's account of the world's first giant computer, the great-great-grandfather of the massive computers used today by the CIA and the National Security Agency.
Intercept!
Authors: Copeland Jack
Published: November 2020

A top-secret cryptographic dictionary compiled by Bletchley Park in 1944 defined ‘Y Service’ as ‘The organisation responsible for the interception of all enemy and neutral radio transmissions’. The job description was succinct, the task huge. The Y Service staff who intercepted and recorded the German and Japanese transmissions are unsung heroes of the attack on the enemy codes. Many of them were women. Their difficult and painstaking work was less glamorous than codebreaking, but without Y the Bletchley cryptanalysts would have had nothing to decrypt. Chapter 2 sketches the growth of the Y Service between the wars, including the establishment of the Royal Navy intercept site at Flowerdown, the Royal Air Force site at Cheadle, and the Army site at Chatham (see photograph 40). These and other military sites in the UK tended to focus on Morse transmissions. Curiously, the interception of the non-Morse transmissions associated with Fish fell at first to the London Police. Collaboration between the Foreign Office signals interception programme and Scotland Yard’s Metropolitan Police wireless service began in 1926 (‘wireless’ means ‘radio’). The Police wireless service, which started life in an attic at Scotland Yard, was originally set up to develop wireless for police vehicles; from 1926 the police operators had the additional brief of intercepting material of interest to the Foreign Office. In 1930 the Foreign Office started to finance the police Y section, which in turn became increasingly involved in the development of experimental equipment for Y work. Following successes against European traffic, the police operators received carte blanche to investigate ‘any curious type of transmission’. In the mid-1930s the section expanded and was relocated to buildings in the grounds of the Metropolitan Police Nursing Home at Denmark Hill in south London. Police operators first intercepted German non-Morse transmissions in 1932, on a link between Berlin and Moscow. These transmissions, which went on for ten months, were clearly experimental, and the police monitored them in conjunction with the Post Office’s Central Telegraph Office. It seems that the pre-war transmissions were unenciphered. Y’s first wartime encounter with non-Morse transmissions came in the latter half of 1940, when two stations broadcasting enciphered teleprinter code were intercepted.
The Testery and the Breaking of Fish
Authors: Edgerley Peter
Published: November 2020

In 1942 I was an 18-year-old schoolboy. My headmaster received a letter from a government department asking him to recommend candidates for work in military intelligence. There was, not unnaturally, little information given about the nature of the work, and certainly no mention of codes or ciphers— but I was sufficiently intrigued and decided to apply. I attended an interview in London, at an address just off Piccadilly. There were five or six interviewers on the panel, some of them civilians. It was a difficult interview, since there was no mention of what the job was. A few weeks later I received a travel warrant and was asked to report to 1 Albany Road in Bedford. I discovered on arrival that I was on a cryptology course. My qualifications were in French and mathematics. Those of us with no German were put on a crash course, in a back room of a hotel a couple of minutes’ walk away from the cryptology school. The German course was nonmilitary in orientation, and the cryptology we were taught was in fact based entirely on English. The cryptology course covered a variety of methods of encryption—nothing hush-hush. We were each issued with a course book, and an instructor came round to give us help with the exercises at the end of each chapter. There were also encrypted messages which we were expected to decrypt. The course lasted about two months. We all knew by then that, if chosen, our next move was to Bletchley Park. I was chosen, but unfortunately there was not enough local accommodation at Bletchley, and I had to stay in Bedford, along with several others who had taken the course. We caught the train to and fro each day, except when returning at midnight after a late shift, when a bus was laid on. Tester’s section—an army section, also employing some civilians on army reserve—was at that time located in Hut 15A, near Enigma Huts 3 and 6 and close to the far end of the tennis court provided for us by Winston Churchill. When Block F was completed we moved there, next door to the much expanded Newmanry with its Colossi.
Systematics, Paleontology, and the Modern Synthesis
Authors: Eldredge Niles
Published: November 2020

Ernst Mayr, a systematist and founding father of the synthetic theory, has recently (Mayr 1980b) assessed the role played by the field of systematics in general in the emergence of the synthesis. Mayr (1980a, 1980b; 1982, chapter 12) actively opposes the conventional supposition that the synthesis is the product of three phases of development: (1) resolution of early difficulties raised in the early days of genetics, largely through the work of Fisher, Haldane, and Wright; (2) the publication of Dobzhansky’s Genetics and the Origin of Species (1937a), which fused concepts of the genetics of populations with the mainstream of Darwinian thought; and (3) the demonstration by systematists (e.g., Mayr 1942), paleontologists (e.g., Simpson 1944), and practitioners of various other biological disciplines that the data of their respective fields are consistent with genetic principles. (See, for example, Shapere 1980, p. 398, for such a view of the historical development of the synthesis.) It is Mayr’s view (e.g., 1980a, 1980b) that these various nongenetics disciplines played a more vital, vigorous and active role than such “me-too-ism” implied by phase 3 above in the conventional view. There is, no doubt, something to be said for this claim, though the historical question per se is not germane to the present inquiry. But Mayr’s (1980b, pp. 127 ff) list of the contributions he feels systematists made directly to the new synthesis is relevant as it suggests a guide to our understanding of Mayr’s own important contribution—Systematics and the Origin of Species (1942, reprinted in 1982). Mayr lists the following contributions of systematics to the emerging synthesis: (1) “population thinking,” (2) “the immense variability of populations,” (3) “the gradualness of evolution,” (4) “the genetic nature of gradual evolution,” (5) “geographic speciation,” (6) “the adaptive nature of observed variation,” (7) “belief in the importance of natural selection,” and (8) the notion (shared with paleontologists) that “macroevolutionary phenomena” are interpretable in terms of “gradual evolution” (i.e., as opposed to saltational models—Mayr 1980b, p. 134). All these topics, and more, are well developed in the pages of Mayr’s Systematics and the Origin of Species.
The Finite-Element Method—Part II
Authors: Kobayashi Shiro , Oh Soo-Ik , Altan Taylan
Published: November 2020

Numerical integration is an important part of the finite-element technique. As seen in Section 6.5 of Chap. 6, volume integrations as well as surface integrations should be carried out in order to represent the elemental stiffness equations in a simple matrix form. In deriving the variational principle, it is implicitly assumed that these integrations are exact. However, exact integrations of the terms included in the element matrices are not always possible. In the finite-element method, further approximations are made in the procedure for integration, which is summarized in this section. Numerical integration requires, in general, that the integrand be evaluated at a finite number of points, called Integration points, within the integration limits. The number of integration points can be reduced, while achieving the same degree of accuracy, by determining the locations of integration points selectively. In evaluating integration in the stiffness matrices, it is necessary to use an integration formula that requires the least number of integrand evaluations. Since the Gaussian quadrature is known to require the minimum number of integration points, we use the Gaussian quadrature formula almost exclusively to carry out the numerical integrations.
Steady-State Processes of Extrusion and Drawing
Authors: Kobayashi Shiro , Oh Soo-Ik , Altan Taylan
Published: November 2020

Except at the start and the end of the deformation, processes such as extrusion, drawing, and rolling are kinematically steady state. Steady-state solutions in these processes are needed for equipment design and die design and for controlling product properties. A variety of solutions for different conditions in extrusion and drawing have been obtained by applying the slip-line theory and the upper-bound theorems. Early applications of the finite-element method to the analysis of extrusion have been for the loading of a workpiece that fits the die and container, and for the extrusion of a small amount of it rather than extruding the workpiece until a steady state is reached. An exception is the work by Lee et al. for plane-strain extrusion with frictionless curved dies using the elastic-plastic finite-element method. In view of the computational efficiency, various numerical procedures particularly suited for the analysis of steady-state processes have been developed by several investigators. Shah and Kobayashi analyzed axisymmetric extrusion through frictionless conical dies by the rigid-plastic finite-element method. The technique involves construction of the flow lines from velocities and integration of strain-rates numerically along flow lines to determine the strain distributions. An improvement of the method was made by including friction at the die-workpiece interface. The steady-state deformation characteristics in extrusion and drawing were obtained as functions of material property, die-workpiece interface friction, die angle, and reduction. In kinematically transient or nonsteady-state forming problems, a mesh that requires continuous updating (Lagrangian) is used. In steady-state problems, a mesh fixed in space (Eulerian) is appropriate, since the process configuration does not change with time. For steady-state problems whose solutions depend on the loading history or strain history of the material, combined Eulerian-Lagrangian approaches are necessary. In deformation of rigid-plastic materials under the isothermal conditions, the solution obtained by the finite-element method is in terms of velocities and, hence, strain-rates. In the nonsteady-state processes, the effective strain-rates are added incrementally for each element to determine the effective strains after a certain amount of deformation.