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  • 2020-min.pdf: ⁠, Chao Min (2020-12-15):

    Highlights:

    • The hypothesis is empirically validated that scientific breakthroughs show distinctive knowledge structure characteristics.
    • A citing-structure perspective is proposed for predicting breakthroughs in their early stage of formation.
    • The number of direct citation counts is of low even negative predictive power.
    • Disciplinary differences exist in knowledge structure of scientific breakthroughs.
    • Timing is critical, and 2- to 3-year-old citing networks have greater predictive power.

    Breakthrough research plays an essential role in the advancement of the scientific system. The identification and recognition of scientific breakthroughs is thus of extreme importance. We propose a citing-structure perspective for observing the unfolding of breakthrough research from variations in knowledge structure. The hypothesis is empirically validated that scientific breakthroughs show distinctive knowledge structure characteristics, which are further utilized to predict breakthroughs in their early stage of formation. These characteristics include average clustering coefficient, average degree, maximum closeness centrality, and maximum eigenvector centrality in the direct citing networks of a breakthrough publication. Several explanations are provided for the effectiveness of the predictive models. We also show that: (1) the number of direct citation counts is of low predictive power, with even a negative impact on prediction performance; (2) disciplinary differences exist in knowledge structure, and this should be taken into account; (3) breakthrough characteristics are most prominent in the first layer of citing networks; (4) timing is critical, and 2- to 3-year-old citing networks have greater predictive power.

  • 2020-greaves.pdf: ⁠, Jane S. Greaves, Anita M. S. Richards, William Bains, Paul B. Rimmer, Hideo Sagawa, David L. Clements, Sara Seager, Janusz J. Petkowski, Clara Sousa-Silva, Sukrit Ranjan, Emily Drabek-Maunder, Helen J. Fraser, Annabel Cartwright, Ingo Mueller-Wodarg, Zhuchang Zhan, Per Friberg, Iain Coulson, E’lisa Lee, Jim Hoge (2020-09-14):

    Measurements of trace gases in planetary atmospheres help us explore chemical conditions different to those on Earth. Our nearest neighbour, Venus, has cloud decks that are temperate but hyperacidic. Here we report the apparent presence of phosphine (PH3) gas in Venus’s atmosphere, where any phosphorus should be in oxidized forms. Single-line millimetre-waveband spectral detections (quality up to ~15σ) from the JCMT and ALMA telescopes have no other plausible identification. Atmospheric PH3 at ~20 ppb abundance is inferred. The presence of PH3 is unexplained after exhaustive study of steady-state chemistry and photochemical pathways, with no currently known abiotic production routes in Venus’s atmosphere, clouds, surface and subsurface, or from lightning, volcanic or meteoritic delivery. PH3 could originate from unknown photochemistry or geochemistry, or, by analogy with biological production of PH3 on Earth, from the presence of life. Other PH3 spectral features should be sought, while in situ cloud and surface sampling could examine sources of this gas.

  • 2020-savarirayan.pdf: ⁠, Ravi Savarirayan, Louise Tofts, Melita Irving, William Wilcox, Carlos A. Bacino, Julie Hoover-Fong, Rosendo Ullot Font, Paul Harmatz, Frank Rutsch, Michael B. Bober, Lynda E. Polgreen, Ignacio Ginebreda, Klaus Mohnike, Joel Charrow, Daniel Hoernschmeyer, Keiichi Ozono, Yasemin Alanay, Paul Arundel, Shoji Kagami, Natsuo Yasui, Klane K. White, Howard M. Saal, Antonio Leiva-Gea, Felipe Luna-González, Hiroshi Mochizuki, Donald Basel, Dania M. Porco, Kala Jayaram, Elena Fisheleva, Alice Huntsman-Labed, Jonathan Day (2020-09-05; backlinks):

    Background: There are no effective therapies for ⁠. An open-label study suggested that administration might increase growth velocity in children with achondroplasia. This phase 3 trial was designed to further assess these preliminary findings.

    Methods: This randomised, double-blind, phase 3, placebo-controlled, multicentre trial compared once-daily subcutaneous administration of vosoritide with placebo in children with achondroplasia. The trial was done in hospitals at 24 sites in seven countries (Australia, Germany, Japan, Spain, Turkey, the USA, and the UK). Eligible patients had a clinical diagnosis of achondroplasia, were ambulatory, had participated for 6 months in a baseline growth study and were aged 5 to less than 18 years at enrolment. Randomisation was done by means of a voice or web-response system, stratified according to sex and Tanner stage. Participants, investigators, and trial sponsor were masked to group assignment. Participants received either vosoritide 15·0 μg/kg or placebo, as allocated, for the duration of the 52-week treatment period administered by daily subcutaneous injections in their homes by trained caregivers. The primary endpoint was change from baseline in mean annualised growth velocity at 52 weeks in treated patients as compared with controls. All randomly assigned patients were included in the efficacy analyses (n = 121). All patients who received one dose of vosoritide or placebo (n = 121) were included in the safety analyses. The trial is complete and is registered, with EudraCT, number, 2015-003836-11.

    Findings: All participants were recruited from Dec 12, 2016, to Nov 7, 2018, with 60 assigned to receive vosoritide and 61 to receive placebo. Of 124 patients screened for eligibility, 121 patients were randomly assigned, and 119 patients completed the 52-week trial. The adjusted mean difference in annualised growth velocity between patients in the vosoritide group and placebo group was 1·57 cm/year in favour of vosoritide (95% CI [1·22–1·93]; two-sided p <0·0001). A total of 119 patients had at least one adverse event; vosoritide group, 59 (98%), and placebo group, 60 (98%). None of the serious adverse events were considered to be treatment related and no deaths occurred.

    Interpretation: Vosoritide is an effective treatment to increase growth in children with achondroplasia. It is not known whether final adult height will be increased, or what the harms of long-term therapy might be.

    Funding: BioMarin Pharmaceutical.

  • 2020-zheng.pdf: ⁠, Richard F. Zheng, Dushyant Barpaga, Paul M. Mathias, Deepika Malhotra, Phillip K Koech, Yuan Jiang, Mukund Bhakta, Marty Lail, Aravind V. Rayer, Greg A. Whyatt, Charles J. Freeman, Andy J. Zwoster, Karl K. Weitz, David J. Heldebrant (2020):

    A comprehensive evaluation of a recently developed water-lean amine-based solvent, namely N-(2-ethoxyethyl)-3-morpholinopropan-1-amine (2-EEMPA), has been performed to analyze its post-combustion CO2 capture performance.

    This evaluation comprises (1) fundamental characterization of the solvent–CO2 interaction using vapor–liquid equilibria, kinetics and viscosity measurements; (2) process characterization of the CO2 capture performance as measured in a laboratory scale continuous flow system and via Aspen Plus® simulation using a flue gas simulant; as well as (3) a full techno economic analysis of the capture process at industrial scale with corresponding projections of critical metrics. This paper summarizes the many parts of this comprehensive evaluation and shows how the various parts come together to empower validated conclusions about its process performance. Notably, it is projected that this solvent can operate at a regeneration heat rate of 2.0 GJ per tonne CO2 for post-combustion capture, and at a total cost of capture of $50.6/tonne CO2.

    With further process optimization substantial reductions in the capture cost are predicted.

  • 2019-tierno.pdf: “Cobalt and Ruthenium drift in ultra-thin oxides”⁠, D. Tierno, O. Varela Pedreira, C. Wu, N. Jourdan, L. Kljucar, Zs. Tőkei, K. Croes

  • 2017-yaremchuk.pdf: ⁠, Kathleen Yaremchuk, Vigen Darian, Amy M. Williams (2017-03-21):

    This retrospective observational analysis hypothesizes that an increase occurs in online reports and images of auricular amputations of confectionary rabbits during the spring.

    Using the online search engine Google, online content and visual portrayals of confectionary rabbit auricular amputations from 2012 to 2017 were identified and trended against seasonal variations. To determine incidence, commercial availability of chocolate rabbits in retail facilities were assayed. A statistically-significant increase in mention of rabbit auricular amputations occurred during the spring. Mapping techniques showed the annual peak incidence for 2012 to 2017 to be near Easter for each year studied. Human adults and children appear to be wholly responsible for the reports of rabbit auricular amputations. Reconstructive techniques are dependent on the percentage of auricular defect.

  • 2014-ma.pdf: ⁠, Xixiu Ma, Murat O. Balaban, Lu Zhang, Emma A. C. Emanuelsson-Patterson, Bryony James (2014-07-21):

    The aim of this study is to quantify the pizza baking properties and performance of different cheeses, including the browning and blistering, and to investigate the correlation to cheese properties (rheology, free oil, transition temperature, and water activity). The color, and color uniformity, of different cheeses (Mozzarella, Cheddar, Colby, Edam, Emmental, Gruyere, and Provolone) were quantified, using a machine vision system and image analysis techniques. The correlations between cheese appearance and attributes were also evaluated, to find that cheese properties including elasticity, free oil, and transition temperature influence the color uniformity of cheeses.

    [Keywords: color uniformity, machine vision, pizza baking, PCA]

    Practical Application: Different cheeses can be employed on “gourmet” style pizzas in combination with Mozzarella. Based on the findings, cheeses with some attributes can be used to cook pizzas to meet the specific preferences of consumers.

  • 2014-nsfnsb-scienceandengineeringindicators2014-ch7.pdf#page=23: ⁠, NSF National Science Board (2014-02-01; backlinks):

    Public Knowledge about S&T: Americans correctly answered 5.8 out of 9 factual knowledge questions in 2012, a score similar to those in recent years.

    • A survey experiment showed that 48% of respondents said they thought it was true that “human beings, as we know them today, developed from earlier species of animals,” but 72% gave this response when the same statement was prefaced by “according to the theory of evolution.” Similarly, 39% of respondents said that “the universe began with a huge explosion,” but 60% gave this response when the statement was prefaced by “according to astronomers.”
    • Levels of factual knowledge in the United States are comparable to those in Europe and are generally higher than levels in countries in other parts of the world.
    • Americans with more formal education do better on science knowledge questions.
    • Men do better on questions focused on the physical sciences, but there are few differences between men and women in terms of responses to questions focused on the biological sciences.

    Most Americans could correctly answer two multiple-choice questions dealing with probability in the context of medical treatment and the best way to conduct a drug trial but had difficulty providing a rationale for the use of a control group or describing what makes something scientific.

    • Americans performed better than the average for residents of 10 European countries on a similar multiple-choice measure of probability, although the residents of several individual countries had better scores than U.S. residents.

    Fewer Americans rejected astrology in 2012 than in recent years.

    • In 2012, slightly more than half of Americans said that astrology was “not at all scientific,” whereas nearly two-thirds gave this response in 2010. The comparable percentage has not been this low since 1983.
  • 2012-borghi.pdf: ⁠, Riccardo Borghi (2012-08-01; backlinks):

    A didactical revisitation of the so-called tumbling toast problem is presented here. The numerical solution of the related Newton’s equations has been found in the space domain, without resorting to the complete time-based law of motion, with a considerable reduction of the mathematical complexity of the problem. This could allow the effect of the different physical mechanisms ruling the overall dynamics to be appreciated in a more transparent way, even by undergraduates. Moreover, the availability from the literature of experimental investigations carried out on tumbling toast allows us to propose different theoretical models of growing complexity in order to show the corresponding improvement of the agreement between theory and observation.

  • 2009-adelberger.pdf: ⁠, E. G. Adelberger, J. H. Gundlach, B. R. Heckel, S. Hoedl, S. Schlamminger (2009; backlinks):

    We review recent mechanical experiments that test some of the most basic principles of physics including the weak and strong forms of the ⁠. The very high sensitivity of these tests allows one to place interesting constraints on string-theory inspired conjectures about new forces from the exchange of very light scalar, pseudo-scalar or vector particles, large extra dimensions, the ⁠, non-commutative spacetime geometry, and Planck-scale Lorentz violation.

    [Keywords: ⁠, equivalence principle, inverse square law, Lorentz invariance]

  • 2006-tai.pdf: ⁠, Robert H. Tai, Christine Qi Liu, Adam V. Maltese, Xitao Fan (2006-05-26; backlinks):

    Young adolescents who expected to have a career in science were more likely to graduate from college with a science degree, emphasizing the importance of early encouragement.

    …We used nationally representative longitudinal data to investigate whether science-related career expectations of early adolescent students predicted the concentrations of their baccalaureate degrees earned years later. Specifically, we asked whether eighth-grade students (approximately age 13) who reported that they expected to enter a science-related career by age 30 obtained baccalaureate degrees in science-related fields at higher rates than students who did not have this expectation. We analyzed students in the United States for years 1988 through 2000 and controlled for differences in academic achievement, academic characteristics, and students’ and parents’ demographics.

    We analyzed (see figure at left) the proportion of students who earned the three types of baccalaureates degrees, according to eighth-grade expectations and math achievement scores. Most notable is the proportion of students who, in a sense, followed through on their eighth-grade science career choices—roughly half. In contrast, proportionally fewer students who reported nonscience career expectations switched into science—roughly a third.

    …Much effort has been focused on raising test scores and promoting advanced courses at later ages; however, we should not overlook the likelihood that life experiences before eighth grade and in elementary school may have an important impact on future career plans. Although our current analysis does not provide proof of an uninterrupted causal chain of influence, our study does suggest that to attract students into the sciences and engineering, we should pay close attention to children’s early exposure to science at the middle and even younger grades. Encouragement of interest and exposure to the sciences should not be ignored in favor of an emphasis on standardized test preparation.

  • 2004-distasi.pdf: ⁠, M. Di Stasi, A. Giannantoni, R. Massoud, P. Navarra, M. Porena, G. Vespasiani, F. Attisani, R. L. Stephen (2004-03-26; backlinks):

    Researchers have reported degradation of RTX [resiniferatoxin] solution stored in various plastic containers. Therefore, we investigated the stability of stock solutions stored in a commonly used plastic material and in glass, under differing conditions of temperature, light and dark…it clearly emerges that: (a) both room temperature and light exposure affect RTX stability and the combined effect of these factors is additive; (b) RTX degradation, if present, falls to a nadir at 48 hours; (c) At low temperatures, in the dark, plastic storage affords better stability than glass.

  • 2001-bacon.pdf: ⁠, M. E. Bacon, George Heald, Matt James (2001-01-01; backlinks):

    The study of the mechanics of tumbling toast provides an informative and entertaining project for undergraduates. The relatively recent introduction of software packages to facilitate the analysis of video recordings, and the numerical solution of complex differential equations, makes such a study an attractive candidate for inclusion in an experimental physics course at the undergraduate level. In the study reported here it is found that the experimentally determined free fall angular velocity of a board, tumbling off the edge of a table, can only be predicted at all accurately if slipping is taken into account. The size and shape of the board used in the calculations and in the experiments were roughly the same as that of a piece of toast. In addition, it is found that the board, tumbling from a standard table of height 76 cm, will land butter-side down (neglecting any bounce) for two ranges of overhang (δ0). δ0 is defined as the initial distance from the table edge to a vertical line drawn through the center of mass when the board is horizontal. For our board (length 10.2 cm) the approximate ranges of overhang are 0–0.8 and 2.7–5.1 cm. The importance of the 0–0.8 cm (only 2% of all possible overhangs for which tumbling is possible) favoring a butter-side down landing should not be underestimated when pondering the widely held belief that toast, tumbling from a table, usually falls butter-side down.

  • 1997-bowden-classicalcomputationcanbecounterfactual.html: ⁠, Keith Bowden (1997-03-15; backlinks):

    We show that at least some classes of classical computation can be carried out counterfactually in a particular sense. By counterfactually we mean that, given a set of quantum superpositions which include the possibility of the (classical) computation being carried out, then an observation can be made such that, even if the computation is not carried out, the result of the computation can be obtained. That is, on some observations, the output of a computer run can be obtained without the computer even being switched on and depends only on the existence of the computer and the possibility of the computation being carried out. As with all counterfactual measurements the proportion of “successful” trials (ie, those in which the computation does not occur, although the result of the computation is obtained) can be made arbitrarily large, but the time taken to get the output is the same as that which would be needed in order to carry out the computation. The interest is in circumstances where there is a reason not to carry out the computation (such as the likelihood that it would permanently change the computer) but we still wish to know the result.

    Although the computation is classical, the overall setup including the measuring device constitutes a quantum computer, and our result is essentially a special case of Josza’s algorithm [Josza, 1995] which shows that all quantum computation [Deutsch, 1985] can be carried out counterfactually. However today’s technology is many years away from building a general quantum computer in Deutsch’s sense. Our paradigm demonstrates that by considering a quantum computer to consist of a combination of classical and nonclassical parts, and by restricting the quantum part to observation and the classical part to computation, we can build interesting devices now. We consider how we can widen the class of counterfactual classical computations and come across some unexpected results and interesting speculations.

  • 1997-appendino.pdf: ⁠, Giovanni Appendino, Arpad Szallasi (1997-01-31; backlinks):

    Resiniferatoxin, an ultrapotent capsaicin analog present in the latex of Euphorbia resinifera, interacts at a specific membrane recognition site (referred to as the vanilloid receptor), expressed by primary sensory neurons mediating pain perception as well as neurogenic inflammation. Desensitization to resiniferatoxin is a promising approach to mitigate neuropathic pain and other pathological conditions in which sensory neuropeptides released from capsaicin-sensitive neurons play a crucial role. Clinical trials to evaluate the potential of topical resiniferatoxin treatment to relieve pain associated with diabetic polyneuropathy and postherpetic neuralgia are in progress. Though resiniferatoxin was isolated only two decades ago, the dried latex of Euphorbia resinifera, called Euphorbium, has been in medicinal use since the time of recorded history. This review highlights the most important events in the history of this ancient medicine, from the first written record of the therapeutic potential of Euphorbium (at the time of the reign of the Roman Emperor Augustus) to the identification of its active principle as resiniferatoxin in 1975. A brief overview of the enormous contribution of resiniferatoxin to our current understanding of the anatomical localization, function, and pharmacology of vanilloid receptors is provided. Lastly, the mechanisms are summarized by which capsaicin and resiniferatoxin, despite sharing receptors, may have dissimilar biological actions.

    [Keywords: euphorbium, resiniferatoxin, capsaicin, vanilloid receptors]

    …Only a few fragments of King Juba’s treatise are left6, thus information on the medicinal use of Euphorbium in this period is rather scanty. Subsequently, Euphorbium is mentioned both in the Greek (e.g. Dioscorides) and Latin (e.g. Pliny the Elder) medical literature as a stemutative (nose irritation) as well as vesicant (skin irritation) agent9. It was also used in the treatment of lethargy: patients could be awakened by “touching their nostrils with a solution of Euphorbium in vinegar”10, with dramatic results, no doubt about it. Other uses of Euphorbium, mentioned by Pliny7, are, however, puzzling, such as the instillation of Euphorbium solutions into the eyes to sharpen sight, or its generalized use against poisons and snake bites. In this case the cure sounds almost worse than the disease: according to Pliny7, no matter where the bite is, an incision is to be made on the skull and the medicament should be inserted there!…During the Renaissance, Euphorbium was widely used as a stemutatory (to provoke sneezing), until its popularity was overshadowed by tobacco5.

    …The irritancy of Euphorbium was legendary. Matthiolus in his above mentioned Pedacio Dioscorides reports that pharmacists refused to pulverize it, leaving this task to “facchini o altre persone vili et mecaniche” (that is, to blue collar workers, in today’s lingo)15. Two hundred years later, powdering Euphorbium was still left to “paysans ou gens de basse condition” (i.e., to peasants and other folks of low social standing)18. No wonder that Euphorbium soon enjoyed a sinister fame among the makers of practical jokes. For example, balls were disrupted by the general sneezing that followed the spreading of Euphorbium powder on the floor23. Such (mis)use of Euphorbium even found its way into the dramatic literature: Panurge, the merry and cowardly companion of Pantagruel in Rabelais’ play, entitled “Gargantua et Pantagruel”, makes fun of a young girl by giving her a beautiful handkerchief sprinkled with Euphorbium powder. The effect is quite dramatic, to Panurge’s highest delight, the poor victim sneezes “quatre heures sans repos” (i.e., four hours without rest).

    …In 1975 Hecker’s group in Germany isolated the active principle in Euphorbium and named it resiniferatoxin (RTX)28. During the drying process, the concentration of RTX in the latex diminishes due to oxidation29, which might explain why “young” samples of Euphorbium were not considered suitable for medicinal purposes. As noted by Matthiolus, “Quello che non passa un anno, per la sua molta attivita non e da usare” (i.e., samples less than one year old should not be used because they are too powerful)15.

  • 1996-adamson.pdf: “Towards the total synthesis of cyclo[n]carbons and the generation of cyclo[6]carbon”⁠, George A. Adamson, Charles W. Rees

  • 1995-matthews.pdf: ⁠, Robert A. J. Matthews (1995-07-18; backlinks):

    We investigate the dynamics of toast tumbling from a table to the floor. Popular opinion is that the final state is usually butter-side down, and constitutes prima facie evidence of Murphy’s Law (‘If it can go wrong, it will’). The orthodox view, in contrast, is that the phenomenon is essentially random, with a 50:50 split of possible outcomes. We show that toast does indeed have an inherent tendency to land butter-side down for a wide range of conditions. Furthermore, we show that this outcome is ultimately ascribable to the values of the fundamental constants. As such, this manifestation of Murphy’s Law appears to be an ineluctable feature of our universe.

  • 1995-dunitz.pdf: ⁠, Jack D. Dunitz, Joel Bernstein (1995; backlinks):

    When a compound exhibits polymorphism—the existence of more than one crystal structure—it may be important to obtain a particular polymorph under controlled and reproducible conditions. However, this is not always easy to achieve. Tales of difficulties in obtaining crystals of a particular known form or in reproducing results from another laboratory (or even from one’s own!) abound. Indeed, there are cases where it was difficult to obtain a given polymorphic form even though this had previously been obtained routinely over long time periods. Several monographs contain explicit or passing references to these problems, but much of this lore has gone undocumented, especially in the last 30 years or so. In this Account we present and discuss old and new examples.

  • 1985-bartlett.pdf: “The slingshot effect: explanation and analogies”⁠, Albert A. Bartlett, Charles W. Hord

  • 1983-edge.pdf: ⁠, D. A. Edge (1983-06-01; backlinks):

    There are many misconceptions about ⁠. He had a delightful and noble character though these features were obscured by his apparently hermit-like way of life. He was self-taught and retired from work as a telegraphist in his early twenties to devote himself to experimentation and writing. He made no money from his epoch-making discoveries and lived and died in near-poverty.

    He is responsible for as we know them and he extended the theory of electro-magnetic wave propagation. He established the mathematical theory of telegraphy and telephony and formulated the condition for distortionless transmission of speech. He found the mathematics of his time unsatisfactory for solving many important problems and consequently invented the which he used to great effect. He predicted the possibility of a reflecting layer in the upper atmosphere (the ) and he was very interested in terminology and coined and defined many new words (e.g., ).

  • 1980-press.pdf: ⁠, William H. Press (1980-01-01; backlinks):

    Why are we the size we are, instead of some very different size? Simple physical scaling laws and three “requirements” dictate that our size be of order (h/2/mee2)(e2/Gmp2)1/4. They also “predict” the mass and radius of the Earth. The three requirements are: (1) We are made of complicated molecules; (2) we breathe an evolved planetary atmosphere; (3) we are about as big as we can be without breaking.

  • 1978-blackford.pdf: ⁠, B. L. Blackford (1978-01-01):

    The basic laws of mass, energy, and momentum conservation are applied to a novel wind-driven water craft. The resulting analysis is an instructive application of these laws, suitable as an undergraduate physics exercise. We find a critical condition which must be met before the boat will accelerate against the wind, and we also obtain expressions for calculating the final speed.

  • 1973-drake.pdf: “Life on a Neutron Star: An Interview With Frank Drake”⁠, Frank Drake (backlinks)

  • 1966-feinberg.pdf: “Physics and the Thales Problem”⁠, Gerald Feinberg

  • 1960-campbell.pdf#page=5: ⁠, John W. Campbell (1960; backlinks):

    [From Analog Magazine, October 1960 (v66, #2), pg87–88.

    Part of a larger article on growing crystals and self-organization. Campbell describes two examples:

    1. glycerine, where attempts to freeze it per a German chemist’s research failed and resulted only in a glass, until they contacted him for information and he sent a sample of his glycerine back, which ‘contaminated’ their own samples and resulted in frozen glycerine but now never glass.
    2. EDT: Bell Labs was growing quartz-substitute crystals called EDT which worked perfectly, replacing expensive quartz, until one day a new polymorph showed up, destroying all EDT crystal production. All attempts to recreate EDT failed, but fortunately, the problem of growing quartz had been solved in the mean time, so it was ultimately not a disaster.]
  • 1950-kohman.pdf: ⁠, G. T. Kohman (1950-01-01; backlinks):

    [Bell Labs account of a bizarre chemical problem.

    Bell manufactured in substantial volume ethylene diamine tartrate (EDT), a piezoelectric synthetic crystal, which it used as a substitute for scarce quartz in telephone line components. While the crystals were usually easy to grow, simply by slicing up crystals and dunking them in solutions, new crystals were sprouting a different EDT crystal, a kind of crystal which grew well in the existing solution and solutions prepared from scratch and solutions made from the new crystals as well, yet was completely worthless. This had happened despite no changes in the manufacturing process.

    Investigation revealed the new crystal was in fact EDT, but a kind with an additional water molecule. This kind was more stable at lower temperatures than the original, and the manufacturing happened to be done slightly under the critical crossover point—and the ‘superior’ EDT form had finally spontaneously happened and now infected all manufacturing. (Because of the instability, any contact with moisture, such cutting crystals with water jets, would make the new form “sprout like fungus growth”.)

    The solution was to eliminate moisture as much as possible, and start manufacturing at temperatures above the crossover point, where the new kind is disfavored.]

  • 1935-urey.pdf: ⁠, H. C. Urey, G. Failla (1935-03-15):

    In discussing the recent press reports of the drinking of by Professor Hansen, of Oslo, the present writers could not account for the “dry burning sensation”…Each of us was then given two identical watch glasses, one containing one cubic centimeter of ordinary distilled water, and the other the same amount of pure heavy water…Neither of us could detect the slightest difference between the taste of ordinary distilled water and the taste of pure heavy water.

  • 1905-einstein.pdf: “Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig? [Does the Inertia of a Body Depend upon its Energy-Content?]”⁠, Albert Einstein

  • 2019-04-10-tylercowen-edboydenonmindingyourbrainep64.html (backlinks)

  • 1966-mathematicalassociationofamerica-documentary-maavideoclassics2-johnvonneumanadocumentary.mkv