DOCSLIB.ORG

Primordial Sex Facilitates the Emergence of Evolution

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Primordial Sex Facilitates the Emergence of Evolution Primordial Sex Facilitates the Emergence of Evolution Sam Sinai1,2,∗, Jason Olejarz1,∗, Iulia A. Neagu1,3, and Martin A. Nowak1,2,4,† 1Program for Evolutionary Dynamics, Harvard University, Cambridge, Massachusetts 02138, USA 2Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA 3Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA 4Department of Mathematics, Harvard University, Cambridge, Massachusetts 02138, USA∗ (Dated: December 11, 2017) Compartments are ubiquitous throughout biology, yet their importance stretches back to the origin of cells. In the context of origin of life, we assume that a protocell, a compartment enclosing functional components, requires N components to be evolvable. We calculate the timescale in which a minimal evolvable protocell is produced. We show that when protocells fuse and share information, the time to produce an evolvable protocell scales algebraically in N, in contrast to an exponential scaling in the absence of fusion. We discuss the implications of this result for origins of life, as well as other biological processes. A defining characteristic of living organisms is their in aqueous conditions [23, 24], forming compartments, ability to replicate and evolve [1]. A major objective of which in this context are known as protocells. research on the origin of life is therefore to find plausi- Protocells alleviate some of the pitfalls that an im- ble chemical systems that are capable of self-replication. pede the transition from prelife to life. The contents of The “RNA world hypothesis” is a leading framework en- protocells are held near each other and share the same compassing theories about the role of RNA in the origin fate. This results in increased interactions within the of life. It postulates that RNA or a similar bio-polymer, protocell and decreased interactions with the outside en- being both an information-carrying molecule, as well as vironment. It also means that the protocell can house an enzymatic one, must have played a central role in a segmented genome, i.e. the information within the initiating self-replication [2–4]. But formidable difficul- protocell need not be stored in one contiguous polymer. ties remain for developing this narrative into a complete It can also dampen the effects of side reactions for any and rigorous theory of the origin of life. Both theoreti- auto-catalytic cycles that may be required to start and cal and experimental investigations show that well-mixed maintain a metabolism [25]. Protocells can also divide populations of RNA or similar bio-polymers often suffer into new protocells that inherit parts of their contents from calamitous pitfalls, including the error catastrophe [26, 27]. These properties of protocells enable them to for replicases [5] and parasitism for cooperative enzymes help in selection for cooperative polymers, in particular [6–9]. Moreover, the complexity of long RNA sequences replicases [6, 7, 28–32]. In addition to enclosing informa- that could serve as efficient catalysts creates a challenge tion and dividing, protocells are able to merge, thereby for explaining their spontaneous prebiotic synthesis [10]. sharing their contents [25, 33–35]. In biology, sharing in- Indeed, despite decades of efforts in prebiotic chemistry formation content between two individuals is considered (and some exciting progress, e.g. [11, 12]), building effi- a defining property of sex. cient, stable, and prebiotically plausible replicases (some- The implications of this information-sharing ability times called the holy grail of the RNA world) has re- among protocells, which is a form of “primordial sex”, mained a challenge [13, 14]. have not received much attention. For reasons outlined arXiv:1612.00825v2 [q-bio.PE] 8 Dec 2017 In modern cells, lipid membranes compartmentalize in the rest of this study, we suggest that the ability for information-carrying and enzymatic molecules akin to these compartments to merge categorically changes the those sought after by RNA world researchers. Hence, at time required to produce an evolvable protocell. Hence, some point in the development of life, either before, dur- we propose that early presence of membranes, possibly ing, or after the emergence of self-replicating genetic el- even before the advent of replication, could have vastly ements, such compartmentalization must have occurred. improved the chances of producing complicated cells by There is evidence in support of the prebiotic availability luck. In such cases it would not be unreasonable to as- of lipid membranes. It has been shown that amphiphilic sume that the starting set of molecules from which an molecules, like simple fatty acids that are building blocks evolvable cell emerges could be large. Almost no origin for the lipid membrane, can be produced in a prebioti- of life models operate on this assumption, because they cally plausible manner [15]. Alternatively, lipids could consider it a probabilistic miracle. have been imported to earth by chondrite meteorites To test this hypothesis, we investigate a simple first- [16–18]. Hence, such molecules were likely abundantly passage process [36, 37]. We assume that in order to be present on the prebiotic Earth [19–23]. These molecules evolvable, a protocell needs to contain a certain number, are able to spontaneously assemble into lipid vesicles N, of component types (i.e., distinct molecules of var- 2 ious complexity) [8, 38–42]. In early life, these could be molecules as simple as ions, activated monomers, molecules that stabilize the membrane, or more compli- cated polymers, like oligo-peptides, and even elementary ribozymes and simple unlinked genes [12, 25, 29, 30, 43– 48]. More precisely, the target set should result in an auto-catalytic network that results in a evolvable cell with non-negligible probability. Such a scheme has been proposed since Oparin, and has been defended more re- cently [48]. We term the smallest set of necessary and sufficient components from which an evolvable protocell can be made a minimal evolvable protocell. We can accordingly represent the functional (or ge- netic) content of each protocell as a binary string of length N. For simplicity, we ignore the redundancy (or dose) of each component in the protocell, and are only concerned with each component’s presence. If a proto- cell contains a particular component i, then the string will have a value of 1 at the ith position and 0 otherwise. Whenever a protocell randomly assembles, we assume that it contains each of the N component types indepen- dently (components do not compete for positions) with FIG. 1. Merging occurs between randomly assembled proto- probability p. I.e. protocell assembly uniformly samples cells. (A) Each color (and a “1” bit at each corresponding each type (with sufficient abundance) from the environ- position on a protocell’s representative binary string) indi- cates presence of one of the four components needed for the ment with probability p. Whenever two protocells merge, protocell to be evolvable (here, N = 4). Randomly assembled the value of the resulting string at every position i is sim- lipid membranes form around the components. (B) When- ply determined by a bitwise OR operation on the ith bits ever two protocells merge, they share their contents. Sharing of the two parent protocells (i.e. if either of the origi- of contents is computed as a bitwise OR operation between nal cells contain a component, the resulting cell will also each of the two parent strings of length N. contain it). This is shown schematically in Figure 1. The dynamical process is as follows. On the first step, the accumulator—the object of our attention—consists number of random assembly and merging events in the of a randomly assembled protocell. If less than N com- accumulation process. ponents are enclosed, then one of two things can happen: The time, Z, needed to form a minimal evolvable pro- With probability δ, the accumulator loses its contents, tocell is thus a random variable that depends on the par- and on the second step, the accumulator consists of a ticular accumulator being tracked. If we track many such new randomly assembled protocell, with the accumula- accumulators, then what is the mean first-passage time, tion process starting over. The accumulator can lose its E[Z], for an accumulator to achieve all N components contents if, for example, its membrane’s integrity is lost, necessary for evolvability? it is infected by a parasite, or it divides, and the param- Begin by considering the simple case δ = 1 (no merg- eter δ accounts for all such possibilities. Or with proba- ing occurs). If the accumulator consists of a randomly bility 1 δ, on the second step, the accumulator merges assembled protocell that has all N components, then the with a randomly− assembled protocell from the environ- minimal evolvable protocell has been achieved. But if ment, possibly gaining additional components. In this there are less than N components, then the accumulator case, if the accumulator still has less than N components is reset without merging. Thus, the expected number of after merging, then one of two things can happen: With such random assembly events required to accumulate all probability δ, the accumulator loses its contents, and on N components necessary for evolvability, Eδ=1[Z], grows the third step, the accumulator consists of a new ran- exponentially with N, i.e., domly assembled protocell, with the accumulation pro- cess starting over. Or with probability 1 δ, on the third 1 N − E [Z]= step, the accumulator merges with another randomly as- δ=1 p sembled protocell from the environment, possibly gaining additional components. This process continues until the For large values of N, the spontaneous generation of a accumulator gains all N components necessary for evolv- minimal evolvable protocell would be a probabilistic mir- ability. The total number of steps (or time units), Z, acle.
Load more

Recommended publications
  • Electronic Supporting Information Combined X-Ray Crystallographic
    Electronic supporting information Combined X-Ray crystallographic, IR/Raman spectroscopic and periodic DFT investigations of new multicomponent crystalline forms of anthelmintic drugs: a case study of carbendazim maleate. Alexander P. Voronin a), Artem O. Surov a), Andrei V. Churakov b), O. D. Parashchuk c), Alexey A. Rykounov d), Mikhail V. Vener*e) a) G.A. Krestov Institute of Solution Chemistry of RAS, Ivanovo, Russia b) N.S. Kurnakov Institute of General and Inorganic Chemistry of RAS, Moscow, Russia c) Faculty of Physics, Lomonosov Moscow State University, Moscow, Russia d) FSUE "RFNC-VNIITF named after Academ. E.I. Zababakhin", Snezhinsk, Russia e) D. Mendeleev University of Chemical Technology, Moscow, Russia *Corresponding author: Mikhail V. Vener, e-mail: [email protected] Table of Contents: Section Page S1. Computational details S2-S4 Table S1 S4 Table S2 S4 Table S3 S5 Table S4 S6 Table S5 S7 Table S6 S7 Figure S1 S8 Figure S2 S8 Figure S3 S9 Figure S4 S10 Figure S5 S10 Figure S6 S11 Figure S7 S11 Figure S8 S12 Figure S9 S12 Figure S10 S13 Figure S11 S13 Figure S12 S14 References S15 S1 S1. Computational details S1.1 Periodic (solid-state) DFT calculations and lattice energy calculation Periodic DFT computations with all-electron Gaussian-type orbitals (GTO) were performed using Crystal17 [1]. The 6-31G** basis set was used. The tolerance on energy controlling the self-consistent field convergence for geometry optimizations and frequency computations was set to 10−10 and to 10−11 Hartree, respectively. The number of points in the numerical first- derivative calculation of the analytic nuclear gradients equals 2.
    [Show full text]
  • Report Concerning Jeffrey E. Epstein's Connections to Harvard University
    REPORT CONCERNING JEFFREY E. EPSTEIN’S CONNECTIONS TO HARVARD UNIVERSITY Diane E. Lopez, Harvard University Vice President and General Counsel Ara B. Gershengorn, Harvard University Attorney Martin F. Murphy, Foley Hoag LLP May 2020 1 INTRODUCTION On September 12, 2019, Harvard President Lawrence S. Bacow issued a message to the Harvard Community concerning Jeffrey E. Epstein’s relationship with Harvard. That message condemned Epstein’s crimes as “utterly abhorrent . repulsive and reprehensible” and expressed “profound[] regret” about “Harvard’s past association with him.” President Bacow’s message announced that he had asked for a review of Epstein’s donations to Harvard. In that communication, President Bacow noted that a preliminary review indicated that Harvard did not accept gifts from Epstein after his 2008 conviction, and this report confirms that as a finding. Lastly, President Bacow also noted Epstein’s appointment as a Visiting Fellow in the Department of Psychology in 2005 and asked that the review address how that appointment had come about. Following up on President Bacow’s announcement, Vice President and General Counsel Diane E. Lopez engaged outside counsel, Martin F. Murphy of Foley Hoag, to work with the Office of General Counsel to conduct the review. Ms. Lopez also issued a message to the community provid- ing two ways for individuals to come forward with information or concerns about Epstein’s ties to Harvard: anonymously through Harvard’s compliance hotline and with attribution to an email ac- count established for that purpose. Since September, we have interviewed more than 40 individu- als, including senior leaders of the University, staff in Harvard’s Office of Alumni Affairs and Development, faculty members, and others.
    [Show full text]
  • Dawkins on Nowak Et Al. and Kin Selection « Why Evolution Is True 25/03/2011 10:17
    Big dust-up about kin selection « Why Evolution Is True 25/03/2011 10:19 Why Evolution Is True « Bummer Peregrinations » Book Links « Home Big dust-up about kin selection About the Author Search About the Book Excerpt Find » Last August I wrote about a new paper in Nature by three Harvard Research Interests biologists, Martin Nowak, Corina Tarnita, and Edward O. Wilson. Their Reviews Meta paper was, as I called it, a “misguided attack on kin selection,” referring Register Log in to the form of selection in which the reproductive success of a gene Buy the Book (usually a gene that affects behavior) is influenced not only by its effects Amazon.co.uk Links on its carrier, but also by its effects on related individuals (kin) carrying Amazon.com the same gene. This idea, introduced to evolutionary biology by George All posts Barnes & Noble All comments Price and W. D. Hamilton, has been enormously productive, explaining all Borders sorts of things from parental care and parent-offspring conflict to sex Indie Bound Email Subscription ratios in animals and, perhaps most important, the evolution of “altruism.” Nowak et al.’s paper attacked the idea that this form of Enter your email address to selection—based on a gene’s “inclusive fitness”—was important in subscribe to this blog and explaining anything; indeed, they didn’t even see kin selection as a form receive notifications of new of natural selection. My original post details most of my objections to posts by email. their paper. Now, seven months later, Nature has published a spate of objections to the Nowak et al paper: there are five critiques and a response to them by Nowak et al.
    [Show full text]
  • Chem 130L: Science of Cooking (NS) Syllabus, Summer Session 2, 2021
    Chem 130L: Science of Cooking (NS) Syllabus, Summer Session 2, 2021 (Soft) Prerequisite: CHEM99D or equivalent. Days and time: MW: 5:00-6:15pm; TTh: 7:00-8:15pm Location: • Monday & Wednesday: synchronous (or asynchronous) lecture. • Tuesday & Thursday: synchronous (or independent) lab. Instructor: Patrick Charbonneau Office hour: M 4:00-5:00pm (or by appointment), via Zoom. Chef: Todd Ohle Office/lab hours: TTh 30 mins before and after lab (or by appointment), via Zoom. Teaching assistant: TBA Course Description: Gastronomy is increasingly popular, and its main practitioners are stars. But Ferran Adrià, Joan Roca, and Grant Achatz share more than fame. They use science to create gastronomic art that challenges our culinary experience. Traditional techniques used to be followed blindly; they are now deconstructed to bring them to new heights. In this course we explore the science that lies behind the new frontier in taste. Main course objectives: ● Understand some of the science involved in cooking. ● Discover the tools and technologies used by world-leading chefs for their creation. Secondary objectives : ● Develop an interest in culinary creation. ● Educate one’s sense of taste. Students will handle (and taste) food, in order to consolidate the scientific learning. ANY FOOD ALLERGY MUST BE DECLARED ON THE FIRST DAY OF CLASS. Specialized cooking supplies and material will be mailed before the start of the semester. Standard cooking supplies (cream, flour, sugar, etc) and material (see list below) should be obtained on one’s own. Standard supplies and material should be available on time for the lab session, or earlier, when specified in the lab description.
    [Show full text]
  • Martin Nowak Evolutionary Dynamics
    808 Book reviews Euler and Gauss. Such illustrations make one wonder what modern science would look like had nothing from these books ever appeared! Practically every article contains information on terminology and notation proposed by Euler. All are in use in modern mathematics. This observation can be extended. It is emphasized that Euler’s courses present the first educational literature in the modern sense of the word. Euler was the first author to discuss proofs and not to hide the motivation behind his demonstrations. Finkel, Boyer and Alexanderson note that Euler not only shares his way of thinking openly but also warns about possible mistakes. Even Euler’s commentaries on his book about artillery were translated from German into English and French. The second volume, The Early Mathematics of Euler, is intended as a mathematical biography. It presents the original and fascinating story of mathematics in the St Petersburg period of Euler’s life, before his departure to Berlin. C. Edward Sandifer attempts to take readers back into the past and is highly successful in achieving this. The time from 1725 to 1741 is divided into the periods 1725–1727, 1728, 1729–1731, and so on. Each section starts with information on world events, events in Euler’s life, the sum of Euler’s work during the period, and Euler’s mathematical papers appearing in the period. The author then gives an account of every article. Such a presentation creates a distinctive narrative atmosphere—an attractive aspect of the work that has significant merit. One can see how early the huge circle of Euler’s interests was formed.
    [Show full text]
  • Pathways to Modern Chemical Physics
    Pathways to Modern Chemical Physics Bearbeitet von Salvatore Califano 1. Auflage 2012. Buch. xii, 288 S. Hardcover ISBN 978 3 642 28179 2 Format (B x L): 15,5 x 23,5 cm Gewicht: 608 g Weitere Fachgebiete > Chemie, Biowissenschaften, Agrarwissenschaften > Physikalische Chemie schnell und portofrei erhältlich bei Die Online-Fachbuchhandlung beck-shop.de ist spezialisiert auf Fachbücher, insbesondere Recht, Steuern und Wirtschaft. Im Sortiment finden Sie alle Medien (Bücher, Zeitschriften, CDs, eBooks, etc.) aller Verlage. Ergänzt wird das Programm durch Services wie Neuerscheinungsdienst oder Zusammenstellungen von Büchern zu Sonderpreisen. Der Shop führt mehr als 8 Millionen Produkte. Preface This book originates from the suggestion made by several colleagues to extract certain sections from a two-volume book that I recently published in Italian with the Bollati-Boringhieri publishing house. The sections concerned deal with recent developments in chemical physics and the intention was to implement them with additional material in order to produce a book in English, explicitly dealing with the progress of chemical physics, in particular that realized in the last two centuries. As a professor of chemical physics, I felt encouraged to fill this gap by producing a book that could offer to new generations of chemistry students a testimony of the commitments, hopes, and dreams that my generation has experienced throughout this fascinating adventure. Although chemistry has its roots in alchemy, or even earlier in the old Sumerian, Babylonian, and Egyptian cultures, chemical physics became an independent discipline only in the second half of the eighteenth century. At this time the efforts of several scientists interested in developing the basic theoretical aspects of chem- istry and their relationships with physics gave rise to the birth of this new discipline and to the creation of the first chairs and journals of chemical physics.
    [Show full text]
  • From Physical Chemistry to Chemical Physics, 1913-1941
    International Workshop on the History of Chemistry 2015 Tokyo From Physical Chemistry to Chemical Physics, 1913-1941 Jeremiah James Ludwig-Maximillian University, Munich, Germany There has never been one unique name for the intersection of chemistry and physics. Nor has it ever been defined by a single, stable set of methods. Nevertheless, it is possible and arguably rewarding to distinguish changes in the constellation of terms and techniques that have defined the intersection over the years. I will speak today about one such change, the advent and ascendancy of chemical physics in the interwar period. When the young Friedrich Wilhelm Ostwald first began to formulate his campaign for “physical chemistry” in 1877, he used the term almost interchangeably with two others, “general chemistry” and “theoretical chemistry.” According to his vision of what would soon become a new chemical discipline, physical chemistry would investigate and formulate the general principles that underlie all chemical reactions and phenomena. The primary strategy that he and his allies used to generate these principles was to formulate mathematical “laws” or “rules” generalizing the results of numerous experiments, often performed using measuring apparatus borrowed from physics. Their main fields of inquiry were thermochemistry and solution theory, and they avoided and often openly maligned speculations regarding structures or mechanisms that might underlie the macroscopic regularities embodied in their laws.1 In the first decades of the 20th-century, the modern atomic theory was firmly established, and with only a slight delay, the methods of 19th-century physical chemistry lost a considerable proportion of their audience. Theories relying upon atomistic thinking began to reshape the disciplinary intersections of chemistry and physics, and by the end of the 1930s, cutting-edge research into the general principles of chemistry looked quite different than it had at the turn of the century.
    [Show full text]
  • David G. Rand
    DAVID G. RAND Sloan School (E-62) Room 539 100 Main Street, Cambridge MA 02138 [email protected] EDUCATION 2006-2009 Ph.D., Harvard University, Systems Biology 2000-2004 B.A., Cornell University summa cum laude, Computational Biology PROFESSIONAL Massachusetts Institute of Technology 2019- Erwin H. Schell Professorship 2018- Associate Professor (tenured) of Management Science, Sloan School 2018- Secondary appointment, Department of Brain and Cognitive Sciences 2018- Affiliated faculty, Institute for Data, Systems, and Society Yale University 2017-2018 Associate Professor (tenured) – Psychology Department 2016-2017 Associate Professor (untenured) – Psychology Department 2013-2016 Assistant Professor – Psychology Department 2013-2018 Appointment by courtesy, Economics Department 2013-2018 Appointment by courtesy, School of Management 2013-2018 Cognitive Science Program 2013-2018 Institution for Social and Policy Studies 2013-2018 Yale Institute for Network Science Applied Cooperation Team (ACT) 2013- Director Harvard University 2012-2013 Postdoctoral Fellow – Psychology Department 2011 Lecturer – Human Evolutionary Biology Department 2010-2012 FQEB Prize Fellow – Psychology Department 2009-2013 Research Scientist – Program for Evolutionary Dynamics 2009-2011 Fellow – Berkman Center for Internet & Society 2006-2009 Ph.D. Student – Systems Biology 2004-2006 Mathematical Modeler – Gene Network Sciences, Ithaca NY 2003-2004 Undergraduate Research Assistant – Psychology, Cornell University 2002-2004 Undergraduate Research Assistant – Plant Biology, Cornell University SELECTED PUBLICATIONS [*Equal contribution] Mosleh M, Arechar AA, Pennycook G, Rand DG (In press) Cognitive reflection correlates with behavior on Twitter. Nature Communications. Bago B, Rand DG, Pennycook G (2020) Fake news, fast and slow: Deliberation reduces belief in false (but not true) news headlines. Journal of Experimental Psychology:General. doi:10.1037/xge0000729 Dias N, Pennycook G, Rand DG (2020) Emphasizing publishers does not effectively reduce susceptibility to misinformation on social media.
    [Show full text]
  • The Descent of Edward Wilson
    prospectmagazine.co.uk http://www.prospectmagazine.co.uk/magazine/edward-wilson-social-conquest- earth-evolutionary-errors-origin-species/ The descent of Edward Wilson A new book on evolution by a great biologist makes a slew of mistakes The Social Conquest of Earth By Edward O Wilson (WW Norton, £18.99, May) When he received the manuscript of The Origin of Species, John Murray, the publisher, sent it to a referee who suggested that Darwin should jettison all that evolution stuff and concentrate on pigeons. It’s funny in the same way as the spoof review of Lady Chatterley’s Lover, which praised its interesting “passages on pheasant raising, the apprehending of poachers, ways of controlling vermin, and other chores and duties of the professional gamekeeper” but added: “Unfortunately one is obliged to wade through many pages of extraneous material in order to discover and savour these sidelights on the management of a Midland shooting estate, and in this reviewer’s opinion this book can not take the place of JR Miller’s Practical Gamekeeping.” I am not being funny when I say of Edward Wilson’s latest book that there are interesting and informative chapters on human evolution, and on the ways of social insects (which he knows better than any man alive), and it was a good idea to write a book comparing these two pinnacles of social evolution, but unfortunately one is obliged to wade through many pages of erroneous and downright perverse misunderstandings of evolutionary theory. In particular, Wilson now rejects “kin selection” (I shall explain this below) and replaces it with a revival of “group selection”—the poorly defined and incoherent view that evolution is driven by the differential survival of whole groups of organisms.
    [Show full text]
  • Coordination, Indirect Speech, and Self-Conscious Emotions
    The Psychology of Common Knowledge: Coordination, Indirect Speech, and Self-Conscious Emotions The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Thomas, Kyle. 2015. The Psychology of Common Knowledge: Coordination, Indirect Speech, and Self-Conscious Emotions. Doctoral dissertation, Harvard University, Graduate School of Arts & Sciences. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467482 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Psychology of Common Knowledge: Coordination, Indirect Speech, and Self-conscious Emotions A dissertation presented by Kyle Andrew Thomas to The Department of Psychology in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Psychology Harvard University Cambridge, Massachusetts May 2015 © 2015 Kyle Andrew Thomas All rights reserved. Dissertation Advisor: Professor Steven Pinker Kyle Andrew Thomas The Psychology of Common Knowledge: Coordination, Indirect Speech, and Self-conscious Emotions ABSTRACT The way humans cooperate is unparalleled in the animal kingdom, and coordination plays an important role in human cooperation. Common knowledge—an infinite recursion of shared mental states, such that A knows X, A knows that B knows X, A knows that B knows that A knows X, ad infinitum—is strategically important in facilitating coordination. Common knowledge has also played an important theoretical role in many fields, and has been invoked to explain a staggering diversity of social phenomena.
    [Show full text]
  • Materials Science Graduate Program Student Handbook Rev
    Kent State University Materials Science Graduate Program Student Handbook Rev. June/2020 Contents 1. Introduction .......................................................................................................................................... 2 3. Programs Learning Outcomes .............................................................................................................. 2 4. Graduate Program Contact Information ............................................................................................. 3 5. Application Procedure .......................................................................................................................... 3 5.1 Application Deadline ........................................................................................................................... 3 5.2 Application Requirement .................................................................................................................... 4 6. Admission Process ................................................................................................................................ 4 6.1 Admission Decision Timeline .............................................................................................................. 5 7. Financial Support .................................................................................................................................. 5 8. Taxes on Stipend .................................................................................................................................
    [Show full text]
  • Chemistry (CHEM) 1
    Chemistry (CHEM) 1 Chemistry (CHEM) CHEM 117. Chemical Concepts and Applications. 3 Credits. Introduction to general and organic chemistry, with applications drawn from the health, environmental, and materials sciences. Prereq or Coreq: MATH 103, MATH 104 or MATH 107 or Math placement. CHEM 117L. Chem Concepts and Applications Lab. 1 Credit. Introduction to general and organic chemistry, with applications drawn from the health, environmental, and materials sciences. Prereq or Coreq: MATH 103, MATH 104, MATH 107 or Math placement. CHEM 121L. General Chemistry I Laboratory. 1 Credit. Matter, measurement, atoms, ions, molecules, reactions, chemical calculations, thermochemistry, bonding, molecular geometry, periodicity, and gases. Prereq or Coreq: MATH 103 or MATH 107 or Math placement. CHEM 121. General Chemistry I. 3 Credits. Matter, measurement, atoms, ions, molecules, reactions, chemical calculations, thermochemistry, bonding, molecular geometry, periodicity, and gases. Prereq or Coreq: MATH 103 or MATH 107 or Math placement. CHEM 122L. General Chemistry II Laboratory. 1 Credit. Intermolecular forces, liquids, solids, kinetics, equilibria, acids and bases, solution chemistry, precipitation, thermodynamics, and electrochemistry. Prereq: CHEM 121L. CHEM 122. General Chemistry II. 3 Credits. Intermolecular forces, liquids, solids, kinetics, equilibria, acids and bases, solution chemistry, precipitation, thermodynamics, and electrochemistry. Prereq: CHEM 121. CHEM 140. Organic Chemical Concepts and Applications. 1 Credit. Introduction to organic chemistry for pre-nursing and other students who need to meet the prerequisite for CHEM 260. CHEM 150. Principles of Chemistry I. 3 Credits. Chemistry for students with good high school preparation in mathematics and science. Electronic structure, stoichiometry, molecular geometry, ionic and covalent bonding, energetics of chemical reactions, gases, transition metal chemistry.
    [Show full text]