180,025 research outputs found
Letter from T. L. Miller, Reedsburg, Wisconsin, to A. P. Gale, Wonewoc, Wisconsin, October 13, 1914
No full textA single letter from T. L. Miller of Reedsburg, Wisconsin, to A. P. Gale, of Wonewoc, Wisconsin, about the renewal of a certificate
Sequence of infilling events in Gale crater, Mars: Results from morphology, stratigraphy, and mineralogy
No full textGale Crater is filled by sedimentary deposits including a mound of layered deposits,
Aeolis Mons. Using orbital data, we mapped the crater infillings and measured their
geometry to determine their origin. The sediment of Aeolis Mons is interpreted to be
primarily air fall material such as dust, volcanic ash, fine-grained impact products, and
possibly snow deposited by settling from the atmosphere, as well as wind-blown sands
cemented in the crater center. Unconformity surfaces between the geological units are
evidence for depositional hiatuses. Crater floor material deposited around Aeolis Mons
and on the crater wall is interpreted to be alluvial and colluvial deposits. Morphologic
evidence suggests that a shallow lake existed after the formation of the lowermost part of
Aeolis Mons (the Small yardangs unit and the mass-wasting deposits). A suite of several
features including patterned ground and possible rock glaciers are suggestive of periglacial
processes with a permafrost environment after the first hundreds of thousands of years
following its formation, dated to ~3.61 Ga, in the Late Noachian/Early Hesperian.
Episodic melting of snow in the crater could have caused the formation of sulfates and
clays in Aeolis Mons, the formation of rock glaciers and the incision of deep canyons and
valleys along its flanks as well as on the crater wall and rim, and the formation of a lake in
the deepest portions of Gale
Anion coordination and anion-directed assembly: highlights from 1997 and 1998
No full textThis review article highlights advances made in anion coordination chemistry in 1997 and 1998, The first section of the review examines anion receptors that do not contain metal ions, This is followed by a review of metal containing anion receptors in which the metal can function as (i) a coordination site for the anion; (ii) a non-coordinating reporter group that signals the presence of the anion by a perturbation of its physical properties; (iii) an element of a receptor designed to withdraw electron density from a rr-electron system and so increase the affinity of a hydrophobic receptor for anions or (iv) part of a self-assembled array that is binding an anionic guest. The role of anions in directing the self-assembly of complex molecular architectures will also be examined
CAFE OF EVE: a method for designing and evaluating interfaces
No full textFew would doubt the need for good interface design. When we use software over an extended period we may come to appreciate some aspects of the interface whilst abhorring others. We can also appreciate that some software packages are better than others although they perform essentially the same function. Intuitively, we are aware that good interface design enhances the usability of software and makes its functions more accessible to the user. The often quoted knock-on benefits include; greater productivity, fewer errors, and greater user satisfaction. What is needed however, is a mechanism for ensuring that newly designed software encapsulates the positive aspects of interface design whilst minimising the negative. This undertaking requires us to understand what is meant by usability. The CAFE OF EVE project seeks to draw together a normal working context and a controlled laboratory to create a special human factors environment, capitalising on the benefits of ecological validity and experimental control, while seeking to avoid the disadvantages of the two contrasting approaches. In so doing, the research benefits should surpass the benefits typically yielded by either approach taken separately or sequentially. What we are proposing and its emergent properties could constitute a minor revolution in human factors researc
Anion receptor chemistry: highlights from 2007
No full textThis critical review includes advances in anion complexation in the year 2007. The review covers anion receptors that employ amides and thioamides, pyrroles and indoles, ureas and thioureas, guanidinium, ammonium, and imidazolium groups and receptors containing hydroxyl groups. In addition, receptors containing metal ions or Lewis acids are discussed along with anion– interactions and the membrane transport of anionic species by synthetic transporters and channels
Supramolecular chemistry: from complexes to complexity
No full textThis review looks back to the birth of modern supramolecular chemistry with the formation of simple crown ether-alkali metal complexes through to more recent self-assembling molecular systems. The final section of this review speculates on what the future may hold for supramolecular assemblies. This includes new catalysts, self-replicating molecular systems, complexes that might be used for data storage, and the creation of molecular motors
Nash equilibria, gale strings, and perfect matchings
No full textThis thesis concerns the problem 2-NASH of finding a Nash equilibrium of a bimatrix
game, for the special class of so-called “hard-to-solve” bimatrix games. The term “hardto-solve” relates to the exponential running time of the famous and often used Lemke–
Howson algorithm for this class of games. The games are constructed with the help of
dual cyclic polytopes, where the algorithm can be expressed combinatorially via labeled
bitstrings defined by the “Gale evenness condition” that characterise the vertices of these
polytopes.
We define the combinatorial problem “Another completely labeled Gale string” whose
solutions define the Nash equilibria of any game defined by cyclic polytopes, including
the games where the Lemke–Howson algorithm takes exponential time. We show that
“Another completely labeled Gale string” is solvable in polynomial time by a reduction to
the “Perfect matching” problem in Euler graphs. We adapt the Lemke–Howson algorithm
to pivot from one perfect matching to another and show that again for a certain class
of graphs this leads to exponential behaviour. Furthermore, we prove that completely
labeled Gale strings and perfect matchings in Euler graphs come in pairs and that the
Lemke–Howson algorithm connects two strings or matchings of opposite signs.
The equivalence between Nash Equilibria of bimatrix games derived from cyclic polytopes, completely labeled Gale strings, and perfect matchings in Euler Graphs implies that
counting Nash equilibria is #P-complete. Although one Nash equilibrium can be computed in polynomial time, we have not succeeded in finding an algorithm that computes
a Nash equilibrium of opposite sign. However, we solve this problem for certain special cases, for example planar graphs. We illustrate the difficulties concerning a general
polynomial-time algorithm for this problem by means of negative results that demonstrate
why a number of approaches towards such an algorithm are unlikely to be successful
Polarasterias Rousseau & Gale 2018, gen. nov.
No full text<i>Polarasterias</i> Rousseau & Gale gen. nov. <p>urn:lsid:zoobank.org:act: 6A46CC92-9366-4DCB-94B5-7313D76EB0A1</p> Type species <p> <i>Polarasterias janusensis</i> Rousseau & Gale gen. et sp. nov., by original designation.</p> Diagnosis <p>Asteriid with elongated arms, small disc, very broad ambulacral grooves with narrow adambulacrals and weakly developed or absent actinals. Abactinals cruciform, numerous, forming a rectilinear grid arranged in regular transverse rows of seven or more plates on each side of the arm. Tube feet strongly quadriserial.</p> Etymology <p>To emphasize the polar situation of the locality and with reference to the North Star Polaris.</p>Published as part of <i>Rousseau, Julie, Gale, Andrew Scott & Thuy, Ben, 2018, New articulated asteroids (Echinodermata, Asteroidea) and ophiuroids (Echinodermata, Ophiuroidea) from the Late Jurassic (Volgian / Tithonian) of central Spitsbergen, pp. 1-26 in European Journal of Taxonomy 411</i> on pages 5-6, DOI: 10.5852/ejt.2018.411, <a href="http://zenodo.org/record/3805999">http://zenodo.org/record/3805999</a>
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