bluuebunny/crossref_metadata_2025 huggingface dataset:
Chloranthalactone (Liu), Rumphellaone A (Kuwahara), Lactiflorin (Bach), Echinosporin (Hale), Harveynone (Taylor), (6,7-deoxy)-Yuanhuapin (Wender)
Authors: Taber Douglass F.
Published: November 2020

The lindenane sesquiterpenes, exemplified by chloranthalactone 4, display interesting physiological activity. Bo Liu of Sichuan University assembled (Organic Lett. 2011, 13, 5406) 4 by opening the epoxide 1 to the carbene, which cyclized to 3. Establishment of the relative configuration of sidechain stereogenic centers is a continuing issue in carbocyclic synthesis. Shigefumi Kuwahara of Tohoku University paired (Tetrahedron Lett. 2012, 53, 705) Sharpless epoxidation, to prepare 5, with the Stork epoxy nitrile cyclization, leading to (+)-rumphellaone A 7. Three competing structures had been put forward for the structure of (+)-lactiflorin 10. Thorsten Bach of the Technische Universität München settled (Angew. Chem. Int. Ed. 2012, 51, 1261) this controversy by preparing the most likely structure, 10, and showing that it was congruent with the natural product. A key step in the synthesis was the tethered 2+2 cycloaddition of 8 to give 9. The conversion of a carbohydrate to a carbocycle is a powerful strategy for the enantiospecific construction of natural products. En route to (–)-echinosporin 14, Karl J. Hale of Queen’s University Belfast added (Org. Lett. 2012, 14, 3024) the allene 12 to the enone 11, prepared from glucose, to give the cyclopentene 13. Richard J.K. Taylor of the University of York prepared (Tetrahedron Lett. 2010, 51, 6619) the enone 16 by oxidation of m-iodophenol 15 followed by asymmetric epoxidation. Reduction followed by deprotection and Pd-mediated coupling delivered (–)-harveynone 17. Some of the daphnane diterpene orthoesters, exemplified by (6,7-deoxy)-yuanhuapin 20, are single-digit nanomolar inhibitors of protein kinase C. Paul A. Wender of Stanford University, in the course of initial studies to optimize this remarkable activity, prepared (Nature Chem. 2011, 3, 615) 20 by way of the thermal cyclization of 18 to 19.
The Tan/Chen/Yang Synthesis of Schindilactone A
Authors: Taber Douglass F.
Published: November 2020

Schindilactone A 3 is one of a closely related family of polycyclic lactones that have been used in China for the treatment of rheumatic disease. The synthesis of 3 reported (Angew. Chem. Int. Ed. 2011, 50, 7373) by Ye-Feng Tang of Tsinghua University and Jia-Hua Chen and Zhen Yang of Peking University is an elegant tour of metal-mediated bond construction, as exemplified by the cyclization of 1 to 2. The preparation of 1 began with the Diels-Alder reaction of 4 with the butadiene 5. Addition of methyl magnesium chloride converted 6 to the crystalline lactone 7. Angular hydroxylation followed by ring expansion gave the bromo enone 8, which was homologated to the lactone 11. Apparently, the bulky silyloxy group directed the addition of the butenyl Grignard reagent 10 to the top face of the ketone carbonyl. Hydroxylation of the lactone followed by the addition of 12 then gave 1 as a mixture of diastereomers. Only one of the two diastereomers of 1 could undergo ring-closing metathesis to form the second of the three carbocyclic rings of 3. The two lactol diastereomers were in equilibrium with each other by way of the open-chain enone. When MgBr2 was added to encourage equilibration, the metathesis proceeded to completion to give 2. The tertiary alcohol of 2 was esterified with 2-butynoic acid to give 13. Intramolecular Pauson-Khand cyclization, using the optimized protocol developed by the authors, then delivered the enone 13, completing the last carbocyclic ring of 3. The last remarkable metal-mediated reaction in the synthesis was the oxidative carbonylation of 14 to 15. It is not clear if the postcarbonylation event is direct Pd-mediated C–O bond formation or the intramolecular addition of alkoxide to a transient butenolide. To complete the synthesis, 15 was methylated, then deprotonated and kinetically quenched to set the proper relative configuration of the last methyl group. Remarkably, despite the presence in the molecule of three other acidic protons, including the one that had just been removed and kinetically reset, exposure of the acetate 16 to a large excess of base, followed by oxidation, gave clean conversion to schindilactone A 3.
The Fukuyama Synthesis of Gelsemoxonine
Authors: Taber Douglass F.
Published: November 2020

The compact and highly functionalized Gelsemium alkaloids, exemplified by gelsemine (OHL20060403) and gelsemoxonine 3, offer a substantial challenge. The cytotoxicity of closely related alkaloids adds to the interest in this class. Tohru Fukuyama of the University of Tokyo envisioned (J. Am. Chem. Soc. 2011, 133, 17634) that cyclopropane-accelerated Cope rearrangement of 1 could deliver 2, ready for further functionalization to 3. The starting material for the synthesis was the enantiomerically pure acetate 4, for which a practical synthetic route was developed. Conjugate addition of 5 then proceeded away from the acetoxy group to give, after intramolecular alkylation, the cyclopropane 6. Selective protection of the derived triol 7 led to a monopivalate that was oxidized to the keto aldehyde 8. Condensation with the oxindole 9 followed by silylation then completed the assembly of 1. The trisubstituted alkene of 1 was established as a single geometric isomer. It followed that in the product 2, the oxindole and the bridging ether had the appropriate relative stereochemical arrangement. The product silyl enol ether was deprotected with fluoride to liberate the ketone 2. With 2 in hand, the next challenge was the kinetic installation of the less stable secondary aminated stereogenic center. To this end, the aldehyde 10 was exposed to TMS-CN and DBU. Under the reaction conditions, the alkene of the intermediate β,γ-unsaturated silylated cyanohydrin was brought into conjugation. Kinetic quench with allyl alcohol gave 11 with a 4:1 preference for the desired endo diastereomer 11. Inversion of the carboxyl then led to the protected amine 12. The ketone 12 was formylated under modified Vilsmeier-Haack conditions, first with Bredereck’s reagent 13 and then with oxalyl chloride, leading to the chloro aldehyde 14. The chlorine was removed by selective Pd-catalyzed reduction, and the product aldehyde was exposed to ethyl magnesium bromide followed by IBX to give the ethyl ketone 15. Epoxidation of the α,β-unsaturated ketone proceeded across the expected exo face leading to 16. The deprotected amine then opened the epoxide to establish the aminated quaternary center and complete the synthesis of gelsemoxonine 3.
The Harran Synthesis of (+)-Roseophilin
Authors: Taber Douglass F.
Published: November 2020

Ansa-bridged prodiginines include (+)-roseophilin B 3 and streptorubin B. The observation that streptorubin B potentiated apoptopic signaling in cell culture led to the development of obatoclax, currently being evaluated for the treatment of leukemia. Patrick G. Harran of UCLA devised (J. Am. Chem. Soc. 2013, 135, 3788) what promises to be a general route to the prodiginines, a key step of which was the cyclization of 1 to 2. In planning the synthesis of 1, the authors took advantage of the relative inertness of a monosubstituted alkene. Friedel-Crafts acylation of 5 proceeded smoothly without affecting the distal double bond. Reduction then completed the preparation of 7. The preparation of 1 continued from the pyrrole 9, prepared from the pyridine 8. Addition of the derived enoate to the aldehyde 10 proceeded smoothly, to give, after oxidation and acid-mediated rearrangement, the furan 12. Selective metalation followed by carboxylation gave the acid 13, which was combined with 7 to give 15. Deprotonation of 15 gave an intermediate that reacted primarily on the pyrrole N. This intermediate was then reacted with diethylchlorophosphite to give, after oxidation, the phosphoramide 16. Advantage was then taken of the organometallic reactivity of the monosubstituted alkene of 16, as Ru-mediated cross metathesis with 17 followed by reduction completed the preparation of 1. The diheteroaryl ketone of 1 is not enolizable. On exposure to KHMDS, the dialkyl ketone will be deprotonated reversibly. Either enolate could add to the diheteroaryl ketone, but only the adduct from deprotonation of the methylene could go on to alkene formation. This net dehydration may likely be driven by phosphoryl transfer to the intermediate alkoxide. The enone 2 is prochiral. Hydrogenation with an enantiopure catalyst proceeded with high de and 67% ee. Remediated intramolecular Friedel-Crafts addition of the dialkyl ketone to the pyrrole followed by acid-mediated rearrangement then delivered (+)-roseophilin 3. There are several points along this synthesis at which diversity could be introduced. This should enable detailed structure–activity studies of the prodiginines.
Pyrite and the Origins of Civilization
Authors: Rickard David
Published: November 2020

Pyrite is an often-overlooked material today although it has been instrumental in enabling many aspects of our modern culture and industry. This bright, brassy mineral is the most abundant metal sulfide in the Earth’s crust and provides a marked chemical contrast to the duller silicates and oxides that constitute most rocks. Most people today are familiar with the mineral, even though they do not know its details, because it stands out in the natural environment and because of the connection with fool’s gold. Pyrite has been a source of both metals and sulfur since ancient times, and both of these commodities have been key to our civilization. The mineral is easily decomposed by heat with the production of sulfur, sulfur oxide gases, and a metal-rich slag. It oxidizes readily in aerated water to form red and yellow ochers that may be used as pigments. It commonly occurs with other valuable metals that may be extracted by leaching or heating with various fluxes. In summary, it is an exceptional mineral whose benefits were readily available to primitive societies and have led to the development of our modern civilization. One of the extraordinary facets of our modern civilization is that we take lighting fires for granted. All you need is a cheap match. However, this is a relatively recent invention. So how did the early Victorians and their predecessors light their fires? Old films and television series, the so-called costume dramas, rarely, if ever, show people lighting fires. One reason for this was that lighting a fire could be a long process, so once it was lit, it was kept going. Even I remember that letting the fire go out was a heinous crime in the days before central heating, when our house was heated by a coal fire. The fire was kept going during the coldest winter weeks: it was banked up at night with coal, which kept it nicely smoldering while we slept. Its heat prevented the water pipes in the house from freezing during the iciest nights and subsequently bursting when they were warmed up again.
The National Environmental Policy Act of 1969, the Rise of Environmental Protection in the 1970s, and the Political Drama of the Next Three Decades
Authors: Conant James K. , Balint Peter J.
Published: November 2020

The National Environmental Policy Act (NEPA) was approved unanimously in the Senate and with near unanimity in the House of Representatives in December 1969. President Nixon signed the act into law on January 1, 1970. The new statute was both brief and farsighted. In fewer than 3,500 words the congressional authors of NEPA articulated for the first time a national policy on the environment, set in motion an innovative regulatory process centered on environmental impact statements, institutionalized public participation in federal environmental decision making, and introduced the requirement that the president report annually to Congress on the nation’s environmental status and trends. NEPA also included a provision that established a new agency, the Council on Environmental Quality (CEQ), in the Executive Office of the President. The CEQ’s assigned statutory role was to implement the environmental impact statement process, prepare the president’s annual environmental report on the condition of the environment, develop policy proposals for solving environmental problems, and coordinate efforts across the federal government to address environmental concerns. As stated in the law, NEPA is designed to “encourage productive and enjoyable harmony between man and his environment”; to “promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man”; and to “fulfill the responsibilities of each generation as trustee of the environment for succeeding generations.” The references to promoting harmony between people and the environment, protecting the biosphere, and affirming the nation’s responsibility for environmental stewardship illustrate an understanding of the scope, scale, and significance of environmental matters that was significantly ahead of its time. The language in NEPA quoted above anticipated by twenty years the concern for the Earth’s biosphere and the concept of environmental sustainability that would become more widely articulated in the run-up to the 1992 Earth Summit in Rio de Janeiro. Moreover, NEPA has had an enduring global impact. By the law’s fortieth anniversary, a majority of U.S. states had established their own environmental impact statement requirements and more than 160 nations worldwide had adopted similar legislation.
EDF Diversifies into New Environmental Arenas
Authors: Wurster Charles F.
Published: November 2020

Environmental law was essentially nonexistent in 1969, and it was a major goal of EDF to establish, enhance, develop, and use this new strategy for solving environmental problems, not just involving DDT but other issues as well. It wasn’t long after incorporation before EDF was getting much publicity because of its actions, leading to numerous requests for advice and assistance in connection with a variety of environmental problems, along with invitations to become involved in an assortment of issues. Whatever it was or wasn’t, EDF certainly was not all talk and no action. There was clearly plenty of action, which attracted plenty of attention. Conservationists were tired of losing by being reasonable, compromising, and timid. Earth Day was about to arrive, and it was time for action. We also were learning that being a “fund” caused a few problems of its own. Some thought it might be a source of funds for them. A few wondered if we were some sort of mutual fund, so Bob Smolker suggested we sell shares in our fund, which would “pay” negative dividends. His Mystique Committee had many original ideas. For the Long Island trustees and small staff, there was little risk in becoming involved in new cases. We had little money to spend or lose, we had an apparently good idea to pursue for environmental protection, and if somebody sent plane fare, we were on our way. So it was with Clancy Gordon of Missoula, Montana. In fact, he came to us only a few months after EDF’s incorporation. It was “Leap Day,” February 29, 1968, when about 100 women of Missoula gathered at the gates of the Hoerner-Waldorf pulp mill west of town to protest Missoula’s “stinky air.” Sometimes the air was so smoggy that planes could not land, and cars turned on their lights in mid-day. “GASP” read one of the picketer’s signs, “Gals Against Smoke and Pollution.” Other signs said “Phew!,” “Bad Sky Country,” “Our Air Stinks,” “How High is the Big Sky,” “Where’s the Airport?,” and “O, Say Can You See.”
War Stories
Authors: Revesz Richard , Lienke Jack
Published: November 2020

To Representative Marsha Blackburn, Republican of Tennessee, the threat was clear: “Mr. Speaker, there is a war being waged on energy and on coal in this country. But it’s not coming from another country, it is coming from our own government.” Her colleague, Mike Pompeo of Kansas, agreed: “President Obama’s War on Coal means fewer jobs and higher energy costs for Americans.” Those who believed otherwise, Virginia Representative David McKinley warned, were “in dangerous denial.” It was September 20, 2012, two months before a presidential election that would pit incumbent Barack Obama against former Massachusetts governor Mitt Romney, and the United States House of Representatives was preparing to vote on the bluntly titled Stop the War on Coal Act. Democrats on the Energy and Commerce Committee called the proposed legislation, which would strip the EPA of its power to regulate coal-mining operations and coal-fired power plants under a host of federal laws, “the single worst anti-environment bill to be considered in the House this Congress.” But the bill’s sponsors argued that significantly curtailing the EPA’s authority over the coal industry was the only way to prevent the President’s war from claiming “even more victims.” The Stop the War on Coal Act passed the House on September 21, 2012, in a 233–175 vote, with the support of nineteen Democrats. No one thought it had any chance of moving in the Democrat-controlled Senate. Instead, the House’s vote, which would be its last act before election day, was “only meant to be an instrument to bludgeon Obama and other Democrats,” as one commentator put it—a reminder to the coal-country electorate of the existential threat posed by the current President and his party. It hadn’t always been this way. On the contrary, four years earlier, Barack Obama had enjoyed a brief, involuntary tenure as the coal industry’s “spokesperson-in-chief.” About a month after Obama emerged victorious from the 2008 election, the American Coalition for Clean Coal Electricity (ACCCE), a “partnership of the industries involved in producing electricity from coal,” released an advertisement made up entirely of video excerpts from a speech he had given at a September 2008 campaign rally in Lebanon, Virginia.
Revolution
Authors: Levy Sharon
Published: November 2020

The fight over the Humboldt Bay Wastewater Authority (HBWA) project had turned bitter and personal. HBWA’s attorney, John Stokes, and most of its board members had lobbied hard against Arcata’s alternative treatment plan. Dan Hauser, usually diplomatic, seethed with resentment. “HBWA has set itself up as the enemy,” he wrote in a September 1977 opinion piece in the Arcata Union. “Therefore, we have no alternative but to defend ourselves by attacking HBWA . . . We must stop this $52 million boondoggle.” Hauser, still Arcata’s representative on the HBWA board, pledged to work toward the “total redesign or total destruction” of the regional sewage system. Other members of HBWA were growing panicky. The Committee for a Sewer Referendum’s lawsuit kept the board from issuing bonds to finance construction, while inflation caused the project’s already huge price tag to balloon. Concealing the move from Hauser, the board applied for a $5.9 million loan from the US Environmental Protection Agency (EPA). Arcata, at Mayor Hauser’s suggestion, promptly sued HBWA for seeking the loan without the city’s consent. Meanwhile, Hauser organized an appeal for Arcata’s wetland treatment system before the State Water Resources Control Board. The city mustered support from representatives of the US Fish and Wildlife Service and Audubon Society, along with academic experts on Humboldt Bay oysters and low-tech sewage treatment. Wade Rose, the shaggy upstart from the governor’s Office of Appropriate Technology, would speak. After Stokes cross-examined Rose at the regional board hearing, “it became a crusade for the entire Office of Appropriate Technology,” Hauser explains. “They singled out HBWA as the ultimate in obsolete technology and concrete overkill.” When the Arcata contingent arrived at the state board hearing in Sacramento, one of the board members, brandishing a newspaper clipping in his hand, called Hauser forward. The clipping was a story from the Arcata Union, quoting Hauser saying that the marsh project would not get a fair hearing. “He asked why I was there if I believed they were already biased against me,” Hauser remembers. “I told him we have to go through this process to get to the next step.”
A Restless Climate
Authors: McMichael Anthony
Published: November 2020

Instructions Accompanying New Domestic devices are tedious. So, uninstructed, we plunge into assembling the device … and the likely result is all too familiar. By analogy, a basic understanding of the cli­mate system and the forces influencing it will shed more light on later chapters. The climate system has many interacting parts, encompassing the linkages between atmosphere, oceans, land, and ice surfaces. The atmosphere and oceans are the prime global distributors of that part of incoming solar energy that Earth retains in the form of heat, much of which is then re- expressed as water vapor, wind, and ocean currents. As part of the Earth system, the world’s climate is always changing. The internal dynamics of the climate system are complex and region­ally distinctive, and include, on shorter time scales, chaotic behavior. Meanwhile, larger forces are at work. As continents coalesce and then drift apart; as massive mountain ranges get pressed skyward; as Earth’s elliptical orbit around the sun alternates between greater and lesser ro­tundity; as both the tilt and wobble of the planet’s axis vary; as solar sunspots come and go; as fluctuations occur in the great ocean- based regional climatic cycles (the Pacific’s El Niño Southern Oscillation, the Indian Ocean Dipole Oscillation, the North Atlantic Inter- Decadal Oscillation, and others); and as volcanic eruptions enshroud the lower atmosphere— so the world’s climate varies on time- scales ranging from tens of millions of years to just several years. The main engine of the climate system, the atmosphere, is made up of many local circulation subsystems, often interacting with (or “coupled” with) the oceans. At a regional scale, different combinations of local circulation systems account for changes in climate, such as the decline in rainfall in Mesopotamia during the third millennium B.C.E., or the southward encroachment of the Arctic polar vortex that imposed the Big Freeze on much of the north eastern USA in the 2013– 2014 winter.
Climatic Choreography of Health and Disease
Authors: McMichael Anthony
Published: November 2020

Ever Since Humans First looked to the skies for relief, the changing mood of the climate has been assumed to be beyond human control, other than through supplication, ceremony, and ritual sacrifice. In secu­lar modern times, there has been little interest in studying climatic influ­ences on patterns of disease and survival. After all, we can curb cigarette smoking, but we cannot change the climate. Or so we thought. Now, though, there is new interest in understanding how human- driven cli­mate change affects human health, in the present and into the future. The risks to human health extend far beyond the well- known dangers from heat extremes, fires, floods, and mosquito proliferation, as signaled in Chapter 1. Changes in regional climates influence crop yields and livestock productivity and hence the occurrence of hunger, undernutri­tion, and stunted child development; they affect the ranges, seasonality, and rates of many infectious diseases. Heightened extremes of weather precipitate cholera outbreaks in impoverished crowded communities and, given the often destructive impacts of many events, can result in post- traumatic stress, long- term depression, and survivor guilt. The list goes on. There are both physical and mental health conse­quences of rural droughts and climate- exacerbated population displace­ment, migration, and resource conflicts. In the Canadian and Alaskan Arctic region, where 2°C warming has already occurred since 1950, the loss of coastal sea ice and permafrost is disrupting traditional Inuit hunting routines. Without access to prey species such as seals and cari­bou, physical activity levels have decreased and the population’s reliance on imported energy- dense processed foods has increased. Rising levels of obesity, cardiovascular disease, and type II diabetes have been the result. As climate change tightens its grip in coming decades, an increasing portion of all adverse health impacts is likely to result from indirect ef­fects such as reduced food yields, depleted freshwater supplies, and loss of the physical protection provided by reefs, mangroves, and forests. In the past, moderately warmer periods in particular regions, spanning several centuries, often enhanced crop yields and population growth.
The Logic of Competence
Authors: Lupia Arthur
Published: November 2020

This chapter clarifies the logical relationship between the types of information an educator can convey and competence at the types of tasks that people perform. Here is a short summary of the chapter’s main claims: . . . Knowledge of many things does not require recalling “all the facts.” Competence at many tasks does not require knowing “everything.” Trying to give “all the facts” to an audience is usually a sign of inefficiency. Cues and non-declarative memories facilitate competence even when they leave people unable to answer certain fact-based questions about a task. The effectiveness of attempts to increase competence depends on what information is given to whom. For example, when the competence of a group is being measured, not all members of that group must have the same knowledge for the group as a whole to be competent. . . . To improve efficiency, educators should understand what kinds of information are most relevant for increasing knowledge and competence. To reach these conclusions, I rely heavily on two terms: necessity and sufficiency. These terms describe logical relationships between two or more items. Educators who understand these terms can better distinguish information that increases desired competences from information that has no such power. X is a necessary condition for Y if Y can happen only after X happens. For example, suppose that earning at least a million votes is a necessary condition for a candidate to win an election. Two implications follow. First, any candidate who does not earn at least a million votes cannot win the election (which means that there may be no winner). Second, any candidate who earns at least a million votes has the potential to win the election. X is a sufficient condition for Y if X happening means that Y must also happen. Suppose that earning a million votes is sufficient to win the election. Two implications follow. First, any candidate who earns at least a million votes wins the election (which implies that multiple candidates could win). Second, any candidate who does not earn at least a million votes retains the potential to win the election.
Complexity and Framing
Authors: Lupia Arthur
Published: November 2020

Politics includes issues of varying complexity. By complex, I mean issues that have multiple and possibly interrelated attributes. While it is arguable that all issues have multiple parts, I use the notion of issue complexity to draw attention to the fact that some issues have so many attributes that educators must make decisions about which parts to emphasize. Consider, for example, the Patient Protection and Affordable Care Act, which the United States passed in 2010. If you haven’t heard of this bill, you may know it by another moniker: “Obamacare.” One measure of this law’s complexity is its length. It is 906 pages long. The law’s table of contents alone is nearly 12 pages. At 906 pages, and given its frequent use of technical language, it is likely that few citizens, including many candidates for office, are knowledgeable about every part of it. It is inevitable that many, and perhaps most, of the people who express public opinions on this issue base their arguments on knowledge of only a few of the law’s many attributes. (This fact, by the way, does not stop people from labeling as “ignorant” others who disagree with them about this law.) In all such cases, experts, advocates, and interested citizens encourage their audiences to weigh certain attributes of the law more (or less) than others when making decisions about it. Insights from previous chapters can help educators make choices about which of a policy’s or candidate’s many multiple attributes to emphasize when attempting to improve others’ knowledge and competence. From chapter 5, for example, we know that just because an issue is complex, it does not mean that an audience’s decision task is complex. Suppose that the task is whether to vote for a specific candidate for office who promises to defeat the healthcare law in its entirety or a candidate who makes the opposite promise. Suppose that we have consulted the relevant range of values and from that consultation we can define a competent choice in the election as the vote that a person would cast if they understood a specific and large set of facts about the law.
The Triple-Point Planet
Authors: McFarland Ben
Published: November 2020

Let’s move to a vantage point a little quieter: the surface of the moon. It is so still that Neil Armstrong’s footprints remain undisturbed. The only reason the US flag there appears to “fly” is that a wire holds it up. The moon and Mercury stayed still as Mars, Venus, and Earth moved on down the road of geological development. The moon is a “steady” environment, a word whose Middle English roots are appropriately tangled with the word for “sterile.” Nothing moves on the moon, but in its sky Mars, Venus, and Earth move in their orbits, just as they moved on in complexity 4 billion years ago. Out of the whole solar system, Mars and Venus are the most like Earth in size, position, and composition. Mars is smaller, but Venus could be Earth’s twin in size. If Earth and Venus were separated at birth, then something happened to obscure the family resemblance: liquid water brought life. To chemists, liquid is the third phase of matter, between solid and gas, and its presence made all the difference. Mars gleams a bright blood red even to the naked eye, while Venus is choked with thick yellow bands of clouds. Mars is cold enough to have carbon dioxide snow, while Venus is hot enough to melt tin and boil water. Earth’s blue oceans and green continents provide a bright, primary contrast. These three siblings have drastically different fortunes. At first, they looked the same, colored with black mafic basalt and glowing red magma. The original planets were all so hot that their atmospheres were driven off into space. The oceans and the air came from within. Steam condensed into oceans on each planet’s cool basalt surface. Oceans changed the planet. Water is a transformative chemical, small yet highly charged, seeping into the smallest cracks, dissolving what it can and carrying those things long distances. Venus, Earth, and Mars do not look like the moon because they have been washed in water. Mars is dry now, but the Curiosity rover left no doubt that the red planet was first blue with water.
The Risk and Reward of Sunlight
Authors: McFarland Ben
Published: November 2020

Three billion years ago, the Earth may have been a pale orange dot. The first atmosphere was rich in methane and related hydrocarbons, which covered the globe with an orange, smoggy haze like Titan’s. That would change drastically over the next billion years. According to some models, this orange haze entered a period about 2.5 billion years ago in which the methane haze disappeared and then reappeared again, blinking on and off several times like a loose light bulb. Then the methane disappeared for good as another gas, oxygen, took over the atmosphere. Life changed from using methane to using oxygen, and the Earth was terraformed. One thing about measuring the chemistry of an entire planet is that it’s hard to fit billions of years and gigatons of material onto a two-dimensional graph. Yet with oxygen, we can come surprisingly close. Three billion years ago was point A with little oxygen in the air, a state of anoxia. Now we are at point B, an “oxic” state with 20% oxygen. The line between point A and point B had some peaks and valleys along the way, but its trend was uphill. (This graph will play a central role in the next two chapters.) The geologist Donald Canfield and others have found evidence for wispy amounts of free oxygen as far back as 3 billion years ago. Oxygen increased in a trickle and then a flood. Canfield found that surprisingly high amounts of oxygen, possibly almost as high as today’s amounts, existed 2.1 billion years ago. Once the chemical key was found that unlocked oxygen, the atmosphere filled with this reactive gas, allowing other organisms to respire and grow in turn. In other other words, if the Doctor shows up in his TARDIS and invites to you time travel back to 2.1 billion years ago, you might be able to step outside and breathe the air, even without a hastily inserted plot device.
One Step Back, Two Steps Forward
Authors: McFarland Ben
Published: November 2020

In seventh grade, I picked up The Eye of the World, the first in a series of Tolkienesque novels. The author, Robert Jordan, had built a world with several creative innovations, but at heart it was the familiar story of the farm boy who grew up to be king that drew me in. It was clear to all readers that this boy would be the hero of the prophesied Last Battle, but most characters refused to see it. I was frustrated by this by book four and graduated to acceptance by book eight. (Did I mention this was a long series?) It took 14 books and a second author to reach the Last Battle. Even though the direction was clear, the plot was anything but an upward march. The chemical history of the Earth was also anything but an upward march. Once photosynthesis made oxygen and mitochondria used it, a cycle of oxygen- making and oxygen-breaking generated cheap energy for exploring and processing the planet, spreading out energy in sun-driven cycles. The direction of this story was set, toward oxygen and oxidation. But like any long story, the chemical story of Earth’s development took twists and turns, encountering obstacles and opportunities, as the Earth oxidized and grew in complexity. Of these twists, the biggest may be geological rather than biological. In this story, precipitation changed the early Earth. Not “precipitation” meaning rain, but “precipitation” in the chemical sense, as when a solid precipitates inside a test tube. Chemists work and think in the liquid phase, where the “rain” that falls is solid particles, which happen when two atoms discover that they are more stable together as solid than apart as dissolved ions. For chemists, precipitation is usually a disappointment. Some of the most elegant experiments have been ruined by the chemicals “precipitating out” into a soggy mess. In a sense, it was a disappointment when it happened on the early Earth as well, although this disappointment threatened the continued existence of life.
The Return of the Exiled Elements
Authors: McFarland Ben
Published: November 2020

The last page in a comic book is often a cliffhanger, so you’ll be more inclined to buy the next issue. It happens so regularly that as I read through the comic (yes, I still read a comic or two), I find myself trying to anticipate what kind of twist will be on the last page. The best twists are the ones you could have seen coming, but didn’t. The story in this book also has a chemical twist here, near the end. This twist is innovative, expensive, and predictable from chemistry. For this twist, the periodic table plays spoiler. Before the Cambrian explosion, hidden in the nets of signaling proteins within cells and signaling molecules outside cells, the cells held a secret chemical potential that could send a much faster signal, built from four elements involved in two of the balances set up in Chapter 5. This form of signaling would be incredibly expensive, but also incredibly fast. It would be electric in its nature and in its effects, the basis of both muscles and brains. Like water flowing randomly down a rocky slope, this fast signaling built from fast chemistry spread out in many different ways in life. At certain points, evolution came together and converged, repeatedly finding that a particular shape or signal was the best solution to a particular problem. Because the liquid flow of life was increased, it could diverge and converge more quickly, while predictably fitting into the shape of its landscape and efficiently moving downhill. The fast chemistry that forms the basis of fast muscles and faster neurons developed with the Cambrian explosion, along with oxygen and calcium use. The explosion of life provided predators that ate and prey that was eaten. Oxygen’s energy (resulting from its place on the periodic table) allowed more complex food chains, with more predators and more prey. For example, some calculate that more oxygen in the late Cambrian made more predators evolve. In response to this oxygen, certain species moved onto dry land, where they had more contact with that element.
Fall
Authors: Leopold Estella B.
Published: November 2020

In the fall we had great fun picking our orchard apples and harvesting in the garden. There were two old apple trees, undoubtedly planted by the Baxter family in the late 1800s. One bore very large sweet apples, which probably was a Wolf River type, in Mother’s estimation, and the other bore just nice, tasty apples. The trunks of these two trees were ten to twelve inches in diameter, so they were really mature trees. Under and around these apple trees we usually had planted potatoes (our best crop!), corn, and huge beefsteak tomatoes. A slice from a beefsteak tomato warmed by the sun and just picked would cover a whole slab of bread. What fabulous sandwiches these made with mayonnaise. Makes me hungry to think about it. It was always such fun to visit our garden with Mother, as she would get very enthusiastic about our crops. Most fun was to dig potatoes. I might be at the shovel, and Mother with a bucket was collecting the potatoes, which were invariably healthy and robust. We would both get on our knees and feel around for the potatoes. Mother would get excited and ooh and ah about their size, their ruddiness, and their abundance. “Oh, Estella. Look at THAT one! Put your hands through that loose soil and make sure we did not leave any potatoes behind! Those little potatoes are hiding,” she would say, or words to that effect. Boiling these little potatoes up for supper was a special treat, as they were so tasty with butter when lightly cooked. Our corn occasionally bore enough cobs to give us a meal. We usually had good luck with onions, too. To weed this garden we had a one-wheeled cultivator with a hoe or blade attached behind the wheel, which was about one foot in diameter. The wooden handles formed a V sprouting from the axis of the wheel. With two hands one would push this wheeled implement between the rows of crops, and it would turn over the weeds, so one could keep the space between the rows pretty weed-free without too much work.
A More Fitting Analogy
Authors: Allchin Douglas
Published: November 2020

In our culture no one needs a biology class to learn about “survival of the fittest.” Yet one might need instruction to unlearn the misconceptions engendered by the analogy’s potent imagery. In popular perspectives, this single phrase conjures images of humans—however civilized—as brutish organisms vying for jobs, status, and power. Maybe they also compete for prime mates. The language of “survival” resonates with “survivor” contests on television: “Outwit. Outplay. Outlast.” Mention of the “fittest” implies that physical “fitness” and athletic prowess are ideals. At the same time, the extremeness of reference to only the “fittest” implies that a human’s fate seems to be life versus death, fit versus unfit, winning versus losing. In all, cooperation and coexistence give way to warfare, conflict, and backstabbing gossip: “society, red in tooth and claw,” to adapt Tennyson’s phrase. Mostly, life reduces to competition. Cutthroat competition. Through just one expression, all these interpretations seem to have a biological basis. None of them are scientifically justified. “Survival of the fittest” is not a neutral phrase, idly describing natural selection. Instead, through unintended metaphors the language fosters major misconceptions. One might hope to remedy these many confusions. But how? “Survival of the fittest” seems to describe both organic evolution and human culture. So first, one must carefully distinguish the processes of each, functioning at different levels (essay 6). Second, one needs to understand how ideology can be unduly naturalized (or improperly inscribed in “nature”). The phrase was never purely descriptive. It expressed cultural values (essay 7). Even with both these pitfalls resolved, however, problems may persist because of the very language itself. The connotations of the phrase seem inescapable. Here, I consider the misconceptions latent in each individual term: “survival” and “fit”—as well as the “-est” suffix. That may help us craft a more fitting analogy or catchphrase to describe natural selection. Consider first the implications of the word “survival.” What matters to evolution is differences in survival rate at a population level. Differential survival leads to differential reproduction, the essence of natural selection.
To Be Human
Authors: Allchin Douglas
Published: November 2020

Who are we? The question of human nature seems to haunt all disciplines. That may tell us how very “human” the question is. Answers vary widely. Yet scientists—anthropologists, geneticists, ethologists, and developmental and evolutionary biologists—rely on observations and empirical data. Their conclusions thus seem more objective. Biologically, humans are primates. Linnaeus perceived that, even before Darwin. We share our anatomies and physiologies with apes and chimps. But Darwin gave this relationship special meaning. He transformed abstract taxonomy into material genealogy. Ever since, we have characterized our species by its ancestry. Identity and history have merged. “Who we are” is now also the story of human origins: where we came from, how, and why. Each new finding in human evolution seems to fascinate us. The sequencing of the human and chimpanzee genomes was big news, appearing on the cover of Time magazine. Then came the Neanderthal genome. “Ardi” (Ardipithecus ramidus) created a public sensation by replacing Lucy as the earliest known complete hominid skeleton, displayed dramatically on the cover of Science. Then the human-like ape Australopithecus sediba sparked new controversy. Add to this buzz new exhibit halls on human origins at both the American Museum of Natural History and the Smithsonian. And a cascade of books, whose topics range from surveying new fossils, vestigial traits, and genomes to profiling the uniqueness of our brains, bones, genome, and behavior. And television specials. We always seems eager for new perspectives. But perhaps it is time to reassess this sacred bovine: that each new finding yields more-complete understanding of human nature. We might well reflect on our past efforts—with their notable errors and flawed assumptions. What might we learn from those missteps instead? Benjamin Franklin was reportedly among the first to celebrate humans as the only toolmaking animal. Later, evolution seemed to make sense of that. Our hands—especially with their opposable thumbs—once used for climbing trees, seem to have found a new adaptive function: to grasp tools, to shape them, to modify the environment and so enhance survival.
What Was Revolutionary about the Chemical Revolution?
Authors: Best Nicholas W.
Published: November 2020

THE CHANGES TO CHEMICAL theory and practice that took place in late eighteenth-century France were truly revolutionary because of the radical nature of the theoretical and methodological changes that occurred, because they were deliberately so, and because that was the start of a tradition in the philosophy of chemistry. What makes the Chemical Revolution unique among scientific revolutions is that it was anticipated by both philosophers and scientists before it occurred. This meant that the chemists who effected those changes were aware of the subversive nature of their reforms and carried out the revolution in a deliberate fashion. Three major shifts in the science of chemistry coincided in late eighteenth-century France to make the Chemical Revolution the turning point in the history of chemistry: Oxygen chemistry overthrew the reigning phlogiston theory; a cadre of prominently political chemists reformed chemical terminology, providing a new system of names based on oxygen theory; and an empiricopragmatic conception of elements as simple substances replaced a waning belief in hypostatical chemical principles. This last shift (although itself gradual) ensured that the revolutionary changes in theory and nomenclature would be the last truly radical reforms chemistry would ever need. Furthermore, the Chemical Revolution was itself a revolution in the philosophy of chemistry as it forced a change in tacit assumptions about the nature of both matter and scientific knowledge. Moreover, studies of this revolution have long shaped general philosophy of science and continue to do so. Cherry-picking the history of science for examples to fit an a priori philosophical theory should be even less acceptable in philosophy of the special sciences than in other branches of philosophy. If philosophers of science are to learn from history, it should be by analyzing changes within periods that historians recognize as revolutionary and giving a philosophical account. Hence the Chemical Revolution is a crucial point for even the most minimally naturalistic philosophy of chemistry. For some time now, historians of science have understood that the chemistry practiced before the 1770s cannot be dismissed as prescientific mysticism, as was once supposed.
Philosophical Issues in (Sub)Disciplinary Contexts: The Case of Quantum Chemistry
Authors: Gavroglu Kostas , Simões Ana
Published: November 2020

IN A WAY, QUANTUM chemistry was “born” as a philosophical problem: It was, of course, chemistry, but owed its scientific status to physics; it was physics with the promise of explaining all of chemistry. Thankfully, following P. A. M. Dirac’s verdict (1929), this state of affairs, at least some years after 1929, was for a future world, an almost utopian world. In the meantime, chemists, physicists, and mathematicians for about half a century defying Dirac’s soothing call that all is well, but only on principle, brought about a new subdiscipline and all the methodological, epistemological, and philosophical problems that go along with the formation of any subdiscipline. In this chapter we put forward a proposal as to how we can write the history of an “in-between” discipline such as quantum chemistry, suggesting that this proposal can be extended to other “in-between” disciplines. Then, we address the role of theory in chemistry, and specifically in quantum chemistry, including the issues surrounding the ontological status of theoretical entities, and proceed to discuss the implications of the introduction of computers in quantum chemistry and the concomitant reconceptualization of experiment. Finally, we reappraise the question of reductionism from the perspective of the practitioners of quantum chemistry. From the very beginning of the period when chemical problems were examined quantum mechanically, everyone involved in the subsequent developments tried to understand the chemical character of what was begotten in the encounter(s) of chemistry with quantum mechanics. Was quantum chemistry the subdiscipline for all those chemical problems formulated in the language of physics which could be dealt with by a straightforward application of quantum mechanics with, of course, the ensuing conceptual readjustments? Was it the case that chemical problems could be dealt with only through an intricate process of appropriation of quantum mechanics by the chemists’ culture? Furthermore, the development of quantum chemistry brought about new entities whose ontological status was continuously under negotiation: exchange energy, resonance, and orbitals were some of the more intriguing entities.