bluuebunny/crossref_metadata_2025 huggingface dataset:
The Morken Synthesis of (+)-Discodermolide
Authors: Taber Douglass F.
Published: November 2020

The anticancer properties of discodermolide 3 were exciting enough that Novartis undertook a commercial-scale total synthesis. While initial clinical trials were not suc­cessful, it is still a very promising lead structure. James P. Morken of Boston College developed (Angew. Chem. Int. Ed. 2014, 53, 9632) a practical approach, based on the Still–Gennari coupling of the phosphonate 1 with the aldehyde 2. The preparation both of 1 and of 2 showed to advantage the diene borylations that have been developed by the Morken group over the past several years. The alde­hyde 5 was prepared by enantioselective hydroformation of the protected acrolein 4. Borylation of pentadiene 6 followed by diastereoselective addition to 5 set, after oxi­dation, the three new stereogenic centers of 7. Ir-catalyzed hydroboration led to the primary alcohol, that was carried through aldehyde deprotection and oxidation to the ester 8. Oxidation of the alcohol to the acid 9 followed by activation with 10 and cou­pling with the anion 11 then completed the synthesis of 1. The preparation of the key Z-trisubstituted alkene chiron 16 again began with enantioselective hydroformylation of the allyl silyl ether 12 to 13. The addition of 14 proceeded with high diastereoselectivity. Nickel-catalyzed borylation of 15 was also highly diastereoselective, leading to an intermediate that was oxidized to the primary alcohol, then carried on the iodide 16. Pt-catalyzed enantioselective borylation of 6 followed by the addition of chloro­methyl lithium led, after oxidation, to the diol 17. Exposure of the derived bis tosyl­ate to potassium t-butoxide led to facile elimination of the homoallylic tosylate. The remaining tosyl protecting group was then removed reductively to give 18. The Roush reductive aldol protocol using the enolate derived from 19 was applied to the derived aldehyde, leading to 20, that was carried on to 21. Under carefully defined conditions, the E-enolate of 21 coupled efficiently with the allylic iodide 17 to give 2. Still–Gennari coupling with 1 to give 22 followed by selective reduction, deprotection, and lactonization then completed the synthesis of (+)-discodermolide 3.
The Ding Synthesis of Steenkrotin A
Authors: Taber Douglass F.
Published: November 2020

Steenkrotin A 3 was isolated from Croton steenkampianus Gerstner, widely used in folk medicine for the treatment of coughs, fever, malaria, and rheumatism. Hanfeng Ding of Zhejiang University envisioned (Angew. Chem. Int. Ed. 2015, 54, 6905) that the intriguingly compact core of 3 could be assembled by reductive cyclization of the alde­hyde 1 to 2, followed by intramolecular aldol condensation. The diastereoselective assembly of 1 from the cycloheptenone core 4 depended on the conformational preferences of the seven-membered ring. Enol ether forma­tion followed by Rubottom oxidation led to the silyl ether 5. Oxidative rearrange­ment of the tertiary alcohol generated by 1,2-addition to 5 of in situ generated allyl lithium established the enone 6. Again taking advantage of the conformational pref­erence of the seven-membered ring, cyclopropanation of the silyl enol ether derived from 6 proceeded across the open face of the electron-rich alkene to give 7. The other oxygenated quaternary center of 1 was constructed by O-alkylation of 7 with diazo malonate followed by methylation and reduction. Acetylation of the diol 8 proceeded with 10:1 diastereoselectivity, to give, after oxidation, the aldehyde 9. In the first of a sequence of three intramolecular bond-forming reactions, HF.py cyclized the aldehyde onto the endocyclic alkene, and also freed the alcohol, that was alkylated with the dibromide 10 to give 11 as a 1.5:1 mixture of diastereomers. On exposure to SmI2, the major diastereomer cyclized to give a intermediate that was carried on to 1. The minor diastereomer was merely reduced, to a product that could be recycled to 11. With 1 in hand, the stage was set for the second intramolecular cyclization. Even though 1 was predominantly in the lactol form, there was enough of an equilibrium concentration of aldehyde present for the SmI2-mediated cyclization to proceed smoothly to 2. With 2 in hand, in addition to the last intramolecular cyclization, the two stereo­genic centers (marked by an asterisk) had to be inverted. The methyl group adjacent to the ketone was readily equilibrated. The secondary alcohol could be inverted by late-stage oxidation and reduction, and the authors did do that. However, they also observed a small amount of the desired epimeric alcohol 14 from the intramolecu­lar aldol condensation of 12.
Where to Next? Unsolved Questions
Authors: Deamer David W.
Published: November 2020

The first ten chapters of this book are a kind of snapshot that captures the current state of knowledge and proposes a scenario for life’s beginning that is based on the properties of RNA described by Harry Noller in the epigraph (Noller, 2012). Despite this progress, there are still enormous gaps in our understanding that remain to be filled. The purpose of this chapter is to make those gaps explicit for future investigators who might be attracted to the question of how life can begin. Because life is an interacting system of immense complexity, each component of which is essential to cellular function as a living system, the gaps have little in common. They can be presented as a set of questions related to sources and properties of organic compounds, mechanisms for capturing energy, polymerization and replication of nucleic acids, the origin of ribosomes, and the transmission of genetic information. For each question, I will discuss one or more papers that could provide clues to an answer and then add some ideas that might serve as guides to future research. A source of mononucleotides is a problem not just for the hypothesis being presented in this book but for any proposed pathway to the origin of life. Unlike amino acids, there is no obvious source of mononucleotides, for the following reasons: Three different molecular species must be present in an aqueous solution at concentrations sufficient for a reaction to occur. They must somehow, even in this mixture of organic solutes, form a specific ester bond between a phosphate and a ribose, then must form an N-glycoside bond between the ribose and a nucleobase (Fig. 11.1), and these reactions must occur spontaneously in a hydrothermal environment. Furthermore, it is not enough for one base to occur in the solution, all four (adenine, uracil, guanine, and cytosine) must be present.
An Unexpected Partnership
Authors: Rosenstein Donald L. , Yopp Justin M.
Published: November 2020

Facilitating a support group and conducting group psychotherapy require similar skills. For both interventions, the leader encourages constructive interactions between group members in the service of psychological growth. However, there are important distinctions between these two types of groups that impact the relationship between the leader(s) and participants. In group psychotherapy, traditional therapeutic rules apply: Patients receive mental health treatment for a diagnosed condition and are charged a fee for that care; the therapist and patients commit to maintaining the confidentiality of disclosures in the group; and records are kept for medical and legal purposes. In contrast, a support group is not considered formal psychotherapy. Consequently, less stringent rules apply. This distinction influenced how we conducted the Single Fathers Due to Cancer support group. The men were not our patients and we were not their therapists. We were therefore able to partner with them in ways that would not have been possible otherwise. From the beginning, a collaborative spirit defined our work with the fathers. The seeds of partnership were sown during the very first meeting when we welcomed their input and, in response to their feedback, altered both the structure and format of group meetings. In the months and years that followed, our partnership expanded and yielded unexpected benefits for us, the men, and countless other widowed fathers. A quick search of the Internet or any bookstore reveals an abundance of resources for people grieving the loss of a loved one. However, there is remarkably little tailored specifically for widowed fathers. Researchers in the grief and bereavement fields have also largely neglected the challenges these men face. As our work with the fathers in the support group continued and intensified, we felt compelled to bring more attention to this underappreciated clinical need. Our first instinct was to approach this subject academically and we drafted two manuscripts for professional journals. In the first paper, we aimed to raise awareness among our colleagues in the cancer and bereavement communities by highlighting the unique hardships of being a widowed father.
The Grand Periodic Function
Authors: Boeyens Jan C. A.
Published: November 2020

The discovery of material periodicity must rank as one of the major achievements of mankind. It reveals an ordered reality despite the gloomy pronouncements of quantum philosophers. Periodicity only appears in closed systems with well-defined boundary conditions. This condition excludes an infinite Euclidean universe and all forms of a chaotic multiverse. Manifestations of cosmic order were observed and misinterpreted by the ancients as divine regulation of terrestrial events, dictated by celestial intervention. Analysis of observed patterns developed into the ancient sciences of astrology, alchemy and numerology, which appeared to magically predict the effects of the macrocosm on the microcosm. The sciences of astronomy and chemistry have by now managed to outgrow the magic connotation, but number theory remains suspect as a scientific pursuit. The relationship between Fibonacci numbers and cosmic self-similarity is constantly being confused with spurious claims of religious and mystic codes, imagined to be revealed through the golden ratio in the architecture of the Great Pyramid and other structures such as the Temple of Luxor. The terminology which is shared by number theory and numerology, such as perfect number, magic number, tetrahedral number and many more, contributes to the confusion. It is not immediately obvious that number theory does not treat 3 as a sacred number, 13 as unlucky and 666 as an apocalyptic threat. The relationship of physical systems to numbers is no more mysterious nor less potent than to differential calculus. Like a differential equation, number theory does not dictate, but only describes physical behavior. The way in which number theory describes the periodicity of matter, atomic structure, superconductivity, electronegativity, bond order, and covalent interaction was summarized in a recent volume. The following brief summary of these results is augmented here by a discussion of atomic and molecular polarizabilities, as derived by number theory, and in all cases specified in relation to the grand periodic function that embodies self-similarity over all space-time.
Resemioticization of Periodicity: A Social Semiotic Perspective
Authors: Liu Yu
Published: November 2020

Chemical periodicity is arguably one of the most important ideas in science, and it has profoundly influenced the development of both modern chemistry and physics (Scerri 1997, 229). While the definition of periodicity has remained largely stable in the past 150 years, the periodic system has been visualized in a wide range of forms including (to name just a few) tables, spirals, and zigzags. Furthermore, information technology makes it much easier, and offers innovative ways, to produce new versions of periodic depictions (e.g., WebElements (Winter 1993)). The multitude of periodic visualizations arouses growing interest among scholars with different academic backgrounds. For instance, educational researchers and practitioners (e.g., Waldrip et al. 2010) wrestle with the question of which visual representation will most effectively help students master the subject content of periodicity. Likewise, philosophers tend to identify the ultimate display of the periodic system, which they use as evidence to support a realistic view of periodicity (Scerri 2007, 21). Other researchers, however, take a different attitude toward the stunning diversity of periodic depictions. In a seminal paper, Marchese (2013) examines the visualization of periodicity at different stages of history from the perspectives of tabular, cartographic, and hypermedia design. His analysis illuminates the periodic table’s plasticity and endeavors to justify the constant transformation of the periodic displays as a necessary means to meet scientists’ changing needs. While all these studies generally emphasize the importance of periodic depictions in scientific research and education, they tend to give primacy to the notion of “periodic system.” By contrast, the periodic table seems to play a secondary role, which either passively reflects the chemical law or responds to the evolving knowledge of chemical elements. Such a view runs the risk of underestimating the significant function of the periodic table as a productive research tool, one which enabled Mendeleev to successfully predict the existence and the properties of undiscovered elements such as germanium in 1869 (Kibler 2007, 222). It is important to note that science and technology are “both material and semiotic practices” (Halliday 1998, 228, italics in original).
Murray Newman and Moby Doll
Authors: Colby Jason M.
Published: November 2020

For two months, Sam Burich had sat at East Point, on the jagged edge of Saturna Island, staring across the Strait of Georgia and waiting for killer whales. The thirty-eight-year-old Croatian immigrant was not a whaler but a sculptor by trade, though he dabbled in fishing to make ends meet. He had come to East Point at the behest of the Vancouver Aquarium to harvest a whale, not for its blubber or meat but for its body—its form. To pass the time, he played his harmonica, carved hieroglyphs in the sandstone, and chatted with his assistant, twenty-six-year-old fisherman Josef Bauer. On this Thursday, July 16, 1964, just after 11:00 a.m., orcas came into sight. It was J pod, making its way north in pursuit of Fraser River chinook. Bauer saw them first and raced over to load their mounted harpoon gun. Then Burich took over. He knew he would have only one shot as the orcas passed. Most of them were out of range, and Burich needed to hit a whale small enough to kill. Soon he spotted his target, a youngster bobbing along playfully just ninety feet away. Burich took aim and pulled the trigger, detonating the one-and-a-half-ounce powder charge. The steel harpoon, four feet long and two inches thick, hit home. At first, Burich couldn’t believe it, but Bauer’s shouts convinced him. Struck just behind the head, the animal appeared stunned. Burich and Bauer rushed to their boat, the forty-foot Corsair II, moored in a nearby cove. As the men approached the whale, they found a surprising scene. Rather than fleeing from danger, the other orcas had surrounded their injured podmate, raising it to the surface to breathe. It was a touching sight, but Burich knew the reputation of these beasts. Worried the whales would retaliate, like those shot by Marineland’s collectors two years earlier, he and Bauer hung back. Within an hour, the pod had left, and the two men moved in for the kill. But the little orca didn’t want to die.
“All Hell Broke Loose”
Authors: Colby Jason M.
Published: November 2020

On the morning of Sunday, March 7, 1976, Ralph and Karen Munro were still feeling the effects of the previous night’s Tartan Ball. Over coffee, the couple chatted briefly about a newspaper editorial: apparently Sea World was trying to catch killer whales in Puget Sound. Although Ralph was special aide to Republican governor Dan Evans, the couple gave the matter little thought as they prepared to go sailing that afternoon with Bill and Pennie Oliver. Leaving from Olympia, the friends enjoyed a leisurely cruise to Cooper Point and were returning south through Budd Inlet at 3:00 p.m. when they spotted orcas off their port side. When Oliver tacked the thirty-three-foot vessel eastward for a look, Karen grew nervous. Would killer whales attack the boat? “I didn’t know anything about them at that time,” she later noted, “and the name sounded kind of scary.” Ralph reassured her. He had followed the story of Ted Griffin and Namu a decade earlier, and like many Northwesterners he now viewed the species with fondness. But the pleasure boaters quickly realized the whales weren’t alone. In pursuit were the seiner Pacific Maid and a smaller vessel named Orca. The reaction on the sailboat was visceral. “All of a sudden we realized that they were trying to capture these whales,” Karen recalled. “They were going to take our whales away.” Oliver radioed the Coast Guard, but officers responded that they lacked jurisdiction, and when he approached a floating seaplane for help, the pilot said that he was part of the operation. By that time, the animals were cornered in nearby Butler Cove. Determined to intervene, Oliver started his engines and steered into the melee. “Stay away!” yelled the men aboard the Pacific Maid. “We’ve got a permit!” But Oliver ignored them, and at first the intervention seemed to work. The whales made a break to the north, but the boats cut them off, driving the animals to the east side of Budd Inlet just off Gull Harbor. The two capture vessels set their nets, and then came the seal bombs.
Assertiveness level 5
Authors: Bennett Peggy D.
Published: November 2020

In the fifth level of assertiveness, words are harsh, denigrating, and disrespectful. 1. A student uses profanity in the classroom. We shout, “How dare you use that word in my class! Anyone who talks like that is low- class and stupid! You may be both, but you will not use that word in my class again!” 2. A friend tells us he/ she won’t be able to keep a commitment. We shout, “You always do this to me! I should have known that I couldn’t count on you to follow through. I don’t know why I even try to plan something fun for us. Just go ahead and cancel— I’ll find someone else to go with me who is more fun than you, anyway!” The intent in level 5 is to scold, insult, and brandish power. In this level of assertiveness, there is no assertiveness, just aggres­sion. We are mean- spirited, extinguishing nearly any immediate opportunity for peaceful reconciliation. Our facial expression shows hard eyes and extreme tension. Our tone of voice is loud or louder than normal, with an edgy, dismissive tone. Level 5 is all about emotion and using false power to shame, demean, and degrade someone. At this level of anger and sar­casm, we diminish others, whether or not they are present to hear us, whether or not we speak our words aloud. If we are thinking this level of vitriol, we are also likely feeling it. And such venom moves us further away from the calm, centered core to which many of us aspire. We may think that we are powerful as we ream another in level 5. But the power is false. We poison ourselves with the nasty words and extreme tension, even as we think we are upbraid­ing someone else. If we pay attention, we can see and feel the power leaking out of us as we show the worst of ourselves. Level 5 is at odds with healthy schools, healthy teachers, and healthy living. Our level 5 behaviors take a toll on those receiving them and, sometimes even more strongly, on those witnessing them.
Feedback that feeds
Authors: Bennett Peggy D.
Published: November 2020

Ask yourself this question: “What do I want students to believe about themselves when they are in my presence?” When we orient ourselves with this question, it shapes our responsiveness to students. We use words that grow rather than wither, that offer instructive comments rather than give general praise, and that give direction for correction and improvement. We feed learning by utilizing informed, instructional, purposeful feedback. Is your feedback too general to be instructional? “Wonderful!” “Terrific!” “Good work.” “Try harder.” “That’s not it.” Sometimes we can get caught in the dichotomy of delivering either praise or criticism. Praise can be nearly as perilous as criticism. Superiority, inferiority, resentment, and embarrassment are some of the potential side effects of praising students. Empty praise can also become habitual (“Very good!”) and feel manipulative (“You’re so good at that, would you do this for me?”). Some who work with students ask, “How does that make you feel?” This is such a personal question, and it should not substi­tute for asking “What did you learn from that?” or saying “That must feel so satisfying!” It may not be our business to ask or know how others feel, and it does not focus on the problem- solving nature of learning. Other statements to use instead are: “What are you thinking about that?” “How would you describe your dilemma?” “What do you plan to do next?” When we become adept at observational feedback, we open a wide range of additional possibilities. We watch and listen to students, then construct instructional feedback to support their learning. If praise is used, it is most often paired with specific feedback. • “Based on what I’m seeing, this may be confusing for you right now. Is that what you think?” • “Your ideas just seem to bubble up, Emile. But keep them inside now so I can listen to Joshua.” • “What puzzles you about that? I appreciate how you can zero in on the problem.” • “That was about 90 percent accurate. Do you have a sense of how you could make it 100 percent?” • “Appropriate vocabulary. Clear explanation. Solid problem- solving. You figured it out!” [Children] need to know that they are valued for themselves, not merely to the degree to which they meet our expecta­tions or follow our rules.
Downshifting
Authors: Bennett Peggy D.
Published: November 2020

When we are driving a car and shift to a lower gear, we cause the engine to downshift. Sometimes we can hear and feel the drag on the motor as the engine slows the car. As we feel the mechanical tug slowing us down, momentum lags. Description of an engine downshifting is an excellent parallel for what happens in our brains when we confront fear, fatigue, and confusion. Why is downshifting so important to consider? In schools, teachers and students can experience downshift­ing multiple times a day. A problem overwhelms. Criticism and embarrassment threaten. Fear looms. Downshifting happens in our brains as a tug to slow down. Especially when we experience threat or fear, our brains’ reac­tions get primal. As Hart describes it, the primordial slowdown allows us to conserve energy. It is our brain’s way of preparing to fight or flee, readying to attack or run. The fight- or- flight response activates unless we can mitigate the fear. In schools, both teachers and students can feel as if they are perpetually in fight- or- flight mode. When we are tense, angry, or paranoid, our brains do not allow us to calmly or efficiently learn, absorb, or retain. When threat is present, “full use of the . . . cerebral brain is suspended, and the faster acting, simpler brain resources take larger roles” The concept of downshifting can help us be attuned to and wary of the toll that threat takes on learning and functioning. Shutting down or slowing our cognitive functions during a down­shift can cause loss of memory, attention, and concentration. Vitality, calm, and openness are casualties of such a state, for both teachers and students. Investing ourselves in eliminating (or minimizing) fear from our classrooms, hallways, and lunchrooms serves a great pur­pose for our learners. Safety and security allow interest and con­centration. With conscious efforts to stimulate curiosity, inspire effort, and encourage achievement, all while providing safety, the boosts in learning (and teaching) can be exponential.
Neutral responsiveness
Authors: Bennett Peggy D.
Published: November 2020

Learning how to offer neutral responses, in schools and else­where, can improve the tenor of relationships and the envi­ronment for learning. When we “neutral up,” we offer comments rather than judgments, observations rather than evaluations. Neutrally responsive statements can be evidence that we are listening to or participating in an activity or conversation. Yet the neutrality of our responses relieves us from delivering a posi­tion or opinion. Communication flows because the emphasis is on interacting and acknowledging, rather than opining and evaluating. • “I see.” • “I didn’t know that.” • “My poor ears!” • “What an idea!” • “You’re thinking!” • “You may be on to something.” • “I’m listening.” • “I’ve heard you say that before.” When we speak with neutral responsiveness, we are neither criti­cizing nor complimenting; we are neither harsh nor gushy; we are neither agreeable nor disagreeable. One small caveat about our delivery is important here. Be aware that if we speak with too little meaning in our voice, con­versational commentary can fall short, feeling too manipulative, too programmed, or too detached. Neutral responses can sound playful, highly engaged, or mildly interested without being agreeable or disagreeable. Neutrality offers a low- stakes participation in conversations and allows us to be responsive without conveying a position. As your students are busy learning or your colleagues are busy pondering, try being neutrally responsive as you interact with them. See what happens.
Allowing upset
Authors: Bennett Peggy D.
Published: November 2020

Teachers fix things. We face a myriad of fixings daily. We unscramble misunderstandings, clarify errors, and soothe hurt feelings. We don’t always get it right, but we so often try. Our compassion and love for students seep into our responses to them. We want them to be happy, comfortable, and at ease. But sometimes we witness their dis- ease. They are angry, hurt, disappointed. They pout. All these reactions are normal parts of growing and living. But what do we do about them? How do we make it better? How can we fix the upset? We know we can be compassionate about students’ feelings. Yet sometimes it is the “letting go of fixing” that can challenge us. Can we be strong enough to allow others to be upset? Can we let anger, disappointment, or frustration run its course rather than try to alleviate it? Can we know whether it is time to inter­vene or let it be? When others are out of sorts, we sometimes need to allow them simply to experience it. Important growth develops for us all when we realize, “I’ll be okay. I’m just going to be angry [hurt, disappointed] for a while.” Allowing others to be upset is not the same as ignoring their troubles. Compassion and assistance are perennial foundations of being a teacher. We can be kind as we allow others to be upset. They can feel the bad feelings and live through them. They can learn that their hurt is temporary. They can learn that they will bounce back, and when they do, we’ll be right there to help them move along.
Principles of teaching and learning
Authors: Bennett Peggy D.
Published: November 2020

A set of principles for teaching and learning can serve us well. We may become more aware of our aims, more consistent in our communications with students and parents, more articulate at stating our positions, more adept at describing our rationales. There is a security that comes with knowing the principles, the tenets, to which we ascribe. Principles give us a platform for making choices and taking directions. Instead of rudderless improvisation, we can check ourselves to judge if we are on or off the path we have chosen. “Principles are important to us because they shape boundar­ies and supply tracks for our choices and behaviors as teach­ers . . . . Our principles form the foundation on which we base our actions and build our teaching identities . . . . Knowing our principles makes us better teachers. Because we know on what foundations our behaviors are based, we see congruency with those foundations in all that we do, say, and think as we work with students” Bennett and Bartholomew’s principles for teaching and learn­ing provide one example of principles that can guide our school practices. Principle 1: Students have the right to be treated with respect and dignity for their ideas, skills, and stages of development. Principle 2: Students deserve an engaging learning environment in which they feel safe enough to demonstrate freely their understandings and skills through various types of participation. Principle 3: Student learning is the responsibility of both teachers and students. Principle 4: Learning is holistic and constructive. Principle 5: A teacher’s attitudes, behaviors, and methodologies should be compatible with one another. Principle 6: Quality of life is enriched through music and singing.
General Comments
Authors: Dalton David R.
Published: November 2020

Viticulture is the art and science of vine-growing and grape-harvesting. In general, the portions of our planet lying between 20° and 50° latitude on either side of the equator (Figure 1.1) are considered suitable for the vines. In these temperate climates, the tilt of the earth’s axis in relation to the sun results in temperatures in the Northern hemisphere in March (and the Southern hemisphere in September) that rarely fall below about 50° Fahrenheit (F) (10° Celsius [C]). As analytical chemistry and possibilities for genomic and epigenomic analysis have evolved, it has become possible to begin to monitor and understand, in detail, how climate affects wine production. For example, a recent Italian study investigated the changes, over a three-year period, in phenotype of a Vitis vinifera cultivar by looking at the transcriptome. They found that most responses they could follow could be attributed to local early spring weather patterns. While a complete analysis was not reported, it was concluded that weather patterns in the previous year were correlated with current year growth. Much of the biology for raising grapes has been discussed, and while 80% of the world’s grape crop is used for production of wine there have been and remain formidable technical difficulties in breeding grapevines. Part of the breeding problem derives from the fact that grapevines are highly heterozygous outcrossers, and so they do not breed true from seed. But they are good cultivars and are polygenic (poly = many; genic = genes). Their inheritance appears to be controlled by large numbers of genes of minor effect. As a consequence, traditional cultivars, grown in their accustomed places, appear to possess subtle combinations of genes whose totality can be preserved by grafting techniques but not in other ways. That is why it appears that the wines produced by such longstanding and traditional cultivars in the hands of vintners accustomed to their nature have unique characteristics of style and quality. Indeed, it seems that it is largely to encourage and maintain such subtle differences that grapevines are seldom propagated from seedlings (but see below) unless a “new” variety is sought by breeders.
The Leaf
Authors: Dalton David R.
Published: November 2020

Grape leaves are thin and flat. As is common among leaves in general, they are composed of different sets of specialized cells. Today, on average, sunlight reaching their surface is about 4% ultraviolet (UV) (<400 nm), 52% infrared (IR) (>750 nm) and 44% visible (VIS) radiation. Little of the UV and IR are used by plants. As with other leaves that are green, only the red and blue ends of the visible part of the electromagnetic spectrum are absorbed, thus leaving green available by reflection and transmission. On the surface of the leaf (Figure 8.1), the cells of the outermost layer (the epidermis) are designed to protect the inner cells where the workings needed for gathering the sunlight used for photosynthesis and other chemistry necessary to the life of the plant are found. That is, the more delicate cells, beneath the epidermis, are involved in production of carbohydrates as well as the movement of nutrients in and products out of the leaf. The epidermis, exposed to the atmosphere, has cells that are usually thicker and are covered by a waxy layer made up of long- chain carboxylic acids that have hydroxyl groups (–OH) at or near their termini. These so-called omega hydroxy acids can then form esters using the hydroxyl group of one and the carboxylic acid of the next. This yields long-chain polyester polymers called “cutin.” As indicated in the earlier discussion of cells and, in particular, regarding the fatty acids of cell walls, the fatty acids found in the epidermis generally consist of an even number of carbon atoms, and for cutin, the sixteen carbon (palmitic acid) family (Figure 8.2) and the eighteen carbon family (oleic acid bearing a double bond or the saturated analogue stearic acid) are common. While one terminal hydroxyl group is usual (e.g., 16-hydroxypalmitic acid, 18-hydroxyoleic acid, or its saturated analogue 18-hydroxystearic acid) more than one (allowing for cross-linking) is not uncommon (e.g., 10,16-dihydroxypalmitic and 9,10,18-trihydroxystearic acid).
The Light on the Leaves
Authors: Dalton David R.
Published: November 2020

As noted earlier in the general description of the plant cell, there is a site at which photosynthesis, the process which allows plants to capture sunlight and convert it into energy, occurs. It is this process which has produced oxygen on the planet, food for herbivores, and the cool green hills of Earth we enjoy today. The capture of sunlight allows the grape vine to grow and produce fruit. Of course, while the discussion of the “light reactions” (capture of sunlight) and the subsequent so-called “dark reactions” (producing carbohydrates) is necessarily brief here, it is, nonetheless, an exciting story. We are only now beginning to understand a little of it. The earlier picture (Figure 7.1) of the plant cell is repeated here (Figure 9.1) so that the position of the chloroplast is seen. Refer to page 24 for a discussion of the numbered items. As the leaves begin to develop alongside the apical meristem, proplastids, which are present in the meristematic regions of the plant, are formed. Proplastids grow into plas¬tids (such as amyloplasts and chloroplasts) as they mature in different ways dictated by the plant’s DNA. Some plastids (e.g., chloroplasts) carry pigments, discussed more fully below, that allow them to carry out photosynthesis. Others are used for storage of fat, starch (amyloplasts) or specialized proteins. Still other plastids are used to synthesize specialized compounds needed to form different tissues or to produce compounds for protection (e.g., tannins). Each plastid builds multiple copies of its DNA as it grows. If it is growing rapidly, it makes more genome copies than if it is growing slowly. The genes, ignoring epigenetic (literally “above the gene”) and postgenetic (literally “after the gene”) modifications, about which we still have much to learn, encode plastid proteins, the regulation of whose expression controls differentiation and thus which plastid is eventually formed. However, despite the differentiation of plastids, it appears that many plastids remain connected to each other by tubes called stromules through which proteins can be exchanged.
Working in the Dark
Authors: Dalton David R.
Published: November 2020

Three turns of the Calvin cycle (Figure 11.1), allow the conversion of three (3) equivalents of carbon dioxide (CO2) (i.e., 3 C1 units) along with three (3) equivalents of the five-carbon carbohydrate derivative, ribulose-1,5-bisphosphate (i.e., 3 C5 units) to yield three (3) not yet isolated six-carbon adducts, 2-carboxy-3-ketoribitol-1,5-bisphosphate (3 C1 + 3 C5 = 3 C6) to form. The three (3) C6 species then undergo fragmentation to yield six (6) equivalents of the three (3) carbon dihydroxy monocarboxylate, 3-phosphoglycerate (i.e., 3 C6 = 6 C3). A cartoon representation of this process is shown in Scheme 11.1 for one of the three CO2 units. Of the six (6) three-carbon unit equivalents, five (5) are used to regenerate three (3) equiv¬alents of ribulose-1,5-bisphosphate (i.e., 5 C3 = 3 C5), while the sixth three- carbon fragment is now available to combine with another to make a six (6) carbon sugar (2 C3 = 1 C6) such as glucose (C6H12O6) (Figure 11.2). Additionally, as shown in Figure 11.3, 3-phosphoglycerate can be used to make other small compound building blocks such as glyceric acid, lactic acid, pyruvic acid and even acetic acid (after decarboxylation). Ribulose- 1,5-bisphosphate (often abbreviated as RuBP), using the enzyme ribulose- 1,5- bisphosphate carboxylase (EC 4.1.1.39, carboxydismutase, rubisco), catalyzes the Mg2+- dependent conversion of the 1,5- bisphosphate ester of the carbohydrate ribulose with carbon dioxide (CO2) to produce two (2) equivalents of 3- phosphoglycerate (PGA). As shown in the Schemes 11.1 and 11.2. A hypothetical the six carbon intermediate, 2- carboxy- 3- ketoribitol- 1,5- bisphosphate, is often written. It is important to keep in mind that we want the 3- phosphoglycerate for purposes of construction of other important compounds. But, as noted above, three turns of the cycle are necessary to produce six (6) equivalents of 3- phosphoglycerate, and five (5) of them are reused in making the three (3) ribulose- 1,5- bisphosphates necessary to turn the cycle three (3) times.
Flowers
Authors: Dalton David R.
Published: November 2020

Generally, grape vines produce extraneous shoots (“suckers”) on the plant in addition to those growing beyond the few desired on the cordon wanted for proper vine growth. Generally, again, suckers are less fertile than the primary shoots, they crowd the canopy of the vine, and their growth utilizes resources required for proper growth of the primary shoots. Further, the chaotic growth makes it difficult to manage the harvest. A crowded canopy (as will be discussed subsequently) is not a healthy one for grape growth.
As shown in Figures 12.1 and 12.2 and noted earlier, buds (the small part of the vine that lies between the vine’s stem and the leaf stem or petiole) can start alongside the beginning of leaves at the base of the apical meristem. The buds swell and eventually produce shoots. As the shoot grows the flowers appear on a stem from the node, from where leaves have also sprung. That is, grape nodes hold buds that grow into leaves and inflorescences or “clusters of flowers” (i.e., the reproductive portion of a plant) arranged on a smaller stem growing from the node. It is not yet clear, despite recognizing the flow of nutrients and auxins as well as changes in proteins, how, after vernalization (i.e., the ability to flower so that fruit can be set—but only after exposure cold), the plant decides which, leaf or stem bearing flowers, should sprout from the node.
The fundamentals of the coming forth of the buds are often outlined as a three-step process. First there is the formation of uncommitted primordia (primordia refer to tissues in their earliest recognizable stages of development) called “anlagen” (from German, in English, “assets” or “facilities”) at the apices of lateral buds. Second, differentiation of anlagen to form inflorescence primordia or tendril primordia occurs. Finally, flowers form from the inflorescence primordia when activated by phytohormones, nutrients, and growth regulators and when the external conditions of light and temperature are correct.
The Grape Berry
Authors: Dalton David R.
Published: November 2020

Beginning with fruit set (generally the grape berry is now between 1.5 and 3.0 mm, i.e., less than 1/ 8 of an inch in diameter) the grape berry growth is divided into three stages. Stages I and III correspond to periods of rapid growth, and the intervening slow growth phase is called Stage II. Generally the slow growth stage (Stage II) corresponds to the slowing of Stage I and the acceleration of Stage III, but it is clear that different grape cultivars have stages of different lengths even under ostensibly identical conditions. In the first stage of fruit set (also called “nouaison”) the actual development of the flower ovary into the grape berry begins. The seeds in the two seed cavities (the locules) and the flesh (the pericarp) begin to take form. The pericarp separates into the exocarp (the skin with its cuticle—a thin wax coating) and the mesocarp. The mesocarp, as it grows and divides, will eventually (by the end of Stage III) account for more than 90% of the grape’s weight. The exocarp, significantly thinner than the mesocarp, may be only five or six cells thick, and the cuticle only several layers of lipids (waxy, fatty acid esters, and compounds similar to those of cell walls and the chloroplast envelope, see pages 30 and 31). It is in this stage that the as yet undeveloped berries are green and hard (it has been sug¬gested that this is because chlorophyll is present and photosynthesis in the berry—as well as in leaves—is occurring). The berries are low in sugar (sucrose) but high in carboxylic acids, predominately malic acid and tartaric acid along with, generally, a lesser amount of ascorbic acid (vitamin C), hydroxycinnamic acid, and some acidic tannins (Figures 13.1 and 13.2). The grape berry structure is generally divided into three types of tissue: skin, flesh, and seed (Figure 13.3). The first, skin, as already mentioned is also known as exocarp.
General Comments
Authors: Dalton David R.
Published: November 2020

Viticulture, it will be recalled, is the art and science of vine-growing and grape-harvesting, and it was the subject of Sections I–IV (Chapters 1–14). Enology, the subject of this Section (Chapters 15– 20), is the art and science of winemaking. Much of what follows in this brief Chapter on General Comments is expanded upon in other Chapters in this Section. In making the wine, it appears to be generally agreed that where possible it is best to follow the traditional methods to produce the best results. However, it should be clearly understood that work is underway to engineer yeast to make it more alcohol tolerant and to use the yeast to produce specific compounds recognized as being particularly flavorful. Additionally, as the number of vintners has grown, finding the proper oak for casks is becoming ever harder. Therefore, the art of reworking old oak casks or even avoiding them altogether (e.g., by aging wine in the presence of oak chips) may be used. In the same vein, it is widely recognized that stoppers other than cork may be used, so that the day may come when the cork stopper will be a thing of the past. Traditionally, grapes are taken directly from the vineyard to be crushed, and it is still the case in many of the oldest and most respected vineyards that this practice will continue. However, as the use of pesticides and fungicides has increased, methods for rapid washing and then drying of grapes before crushing may be employed. The arguments against these extra steps are mainly two. First, lingering water would dilute the grape juice. Second, the adventitious yeasts that might be removed by washing or deactivated by drying are often desired for the production of the vintage. Indeed, it has been argued that unique fungi, which might be exclusive to the most prestigious vineyards, are important to the production of the best wines. The issue of washing versus not washing has been investigated, and it was concluded for the case examined that only minor changes are effected by washing.
Adding Sulfur Dioxide (SO2)
Authors: Dalton David R.
Published: November 2020

The judicious use of sulfur dioxide (SO2) will inhibit the growth of microorganisms (e.g., bacteria) present on the grape skins as the berries come from the vineyard. Its early use presumes the vintner has decided that the adventitious wild yeasts which might be destroyed or inhibited by sulfur dioxide will not contribute to the vintage. It appears that Saccharomyces cerevisiae might be less susceptible to the action of sulfur dioxide than other yeasts that may be present. So, if the particular strain of S. cerevisiae used can cope, it may be able to function unimpeded. Regardless, sulfur dioxide might still be used because, in addition to suppression of deleterious microorganisms, it appears to reduce oxidation of particularly fragile white wine components. In industrial settings, both gaseous sulfur dioxide and sulfur dioxide as a liquefied gas (boiling point – 10 °C [14 °F]) are used. In either form it is a dangerous tool. It is dangerous first because it is toxic and second because an excess of it will ruin the wine. In many cases, because its value is recognized as beneficial, sulfur dioxide is replaced by addition of either sodium metabisulfite (Na2S2O5) or potassium metabisulfite (K2S2O5) with the latter generally preferred. Indeed, while it is best to look at the MSDS. (Manufacturer’s Safety Data Sheet) before use, the solubility of the two salts is the same and given as 450 grams/ liter (g/ L) at 68 °F (20 °C) and the pH on dissolution as between 3.5 and 4.5. The potassium (K) salt appears, at this writing, to be more readily available in food quality (as opposed to chemical quality) grade. So, with regard to sulfur dioxide (SO2), and as shown in Figure 17.1, its structure is much more similar to water and to ozone than it is to carbon dioxide (CO2); sulfur lies beneath oxygen (O2) in the periodic table (silicon, Si, lies beneath carbon). Nonetheless, sulfur dioxide (SO2) reacts with water much the same way that carbon dioxide (CO2) does.
Sealing the Bottles
Authors: Dalton David R.
Published: November 2020

It has been suggested that containers made of clay (e.g., the amphora of the bronze age) were adopted for use during the thousands of years of winemaking that preceded the ability to produce suitable glass vessels. Sealing the amphora, as reported by archeologists and historians, was accomplished with clay or leaves covered with clay, rags, wax, pine resin (producing retsina), and even today’s popular choice, cork. With the exception of the latter, where only a small amount of air can leak in, it appears that too much air would enter and the flavor of the wine would change. In part, the effort to seal the amphora was futile, as the clay amphora would leak too. But waxes and resins helped seal out air and, in the process, often changed the flavor of the beverage. Again, historically, it appears from analysis of the contents remaining in the old vessels that various flavoring agents, such as berries, fruits, leaves, flowers, and even metals such as lead were intentionally added to wines to suit the tastes of the consumer. Nonetheless, oxidation and bacteria (e.g., Acetobacter aceti, known to convert ethanol [CH3CH2OH] to acetaldehyde [CH3CHO] and thence to acetic acid [CH3CH2OH]) would often make the beverage unpalatable (by today’s tastes). So, tastes were adjusted to fit the beverage available! It was also found that wines that had additional ethanol present were resistant to bacterial action, so tastes (even into the twentieth century) were developed for “fortified” wines (vide infra, Chapter 21) such as Port, Sherry, and Madeira that were to be shipped in casks. More recently shipment of the latter in glass bottles (since late in the nineteenth century) along with cork stoppers have become common. Most recently, synthetic (i.e., polymer) stoppers and aluminum screw caps have been used for all of these beverages because most wine is produced to be consumed within a few years of its bottling. This fairly recent change has arisen as an accommodation to large-scale production, long-distance shipping, and storage in commercial sales facilities, none of which encourage saving wine for aging.