The third and fourth pluricanonical maps of threefolds of general type

2014 ◽  
Vol 157 (2) ◽  
pp. 209-220
Author(s):  
JINSONG XU

AbstractFor a nonsingular projective threefold of general typeXover the field of complex numbers, we show that the fourth pluricanonical map ϕ4is not birational onto its image if and only ifXis birationally fibred by (1,2)-surfaces, provided that vol(X) ≥ 303. We also have similar characterization of birationality of ϕ3.

2014 ◽  
Vol 17 (1) ◽  
pp. 45-71
Author(s):  
Geo Siegwart

The main objective is an interpretation of the island parody, in particular a logical reconstruction of the parodying argument that stays close to the text. The parodied reasoning is identified as the proof in the second chapter of the Proslogion, more specifically, this proof as it is represented by Gaunilo in the first chapter of his Liber pro insipiente. The second task is a detailed comparison between parodied and parodying argument as well as an account of their common structure. The third objective is a tentative characterization of the nature and function of parodies of arguments. It seems that parodying does not add new pertinent points of view to the usual criticism of an argument.


2015 ◽  
Vol 07 (04) ◽  
pp. 1550050
Author(s):  
Carlos J. Luz

For any graph [Formula: see text] Luz and Schrijver [A convex quadratic characterization of the Lovász theta number, SIAM J. Discrete Math. 19(2) (2005) 382–387] introduced a characterization of the Lovász number [Formula: see text] based on convex quadratic programming. A similar characterization is now established for the weighted version of the number [Formula: see text] independently introduced by McEliece, Rodemich, and Rumsey [The Lovász bound and some generalizations, J. Combin. Inform. Syst. Sci. 3 (1978) 134–152] and Schrijver [A Comparison of the Delsarte and Lovász bounds, IEEE Trans. Inform. Theory 25(4) (1979) 425–429]. Also, a class of graphs for which the weighted version of [Formula: see text] coincides with the weighted stability number is characterized.


1988 ◽  
Vol 121 ◽  
Author(s):  
Lawrence W. Hrubesh ◽  
Cynthia T. Alviso

ABSTRACTTwo optical methods are described for mapping the local variations of refractive index within monoliths of porous silica aerogel. One is an interferometrie measurement that produces “iso-index” fringes in a two dimensional image; an orthogonal view gives the third dimension information. The other method uses the deflection of a He-Ne laser beam to map the gradient index within a sample. The quantification of the measurements is described and the accuracy of the results is discussed.


Africa ◽  
1984 ◽  
Vol 54 (2) ◽  
pp. 29-48 ◽  
Author(s):  
David Brown

Opening ParagraphIt is perhaps surprising that the recent resurgence of interest in the application of Marxist theory to the study of the historically non-capitalist societies of the Third World should have focused, at least in part, upon the stateless societies of Africa. To some extent, this interest in some of the least differentiated and least class-stratified of societies can be related to the fundamental problematic of Marxist sociology: the characterization of the stage of advanced communism, which remains so obscure in Marx's own theoretical work. An understanding of the dynamics of ‘primitive’ communism might be seen, therefore, as an essential precursor to this underlying concern. Certainly, the often highly tendentious views of Marxist writers on such issues as the definition of the state and the extent of exploitation in the primitive communist mode can be related to this need. However, the rise of Marxist anthropology has not only been presented as a problem of general evolutionary theory. Other influences have been offered to account for the new concern, the most widely cited being the supposed crisis of functionalism, and the resulting necessity for a complete reorientation of the whole discipline of anthropology. Stateless societies, having long occupied a central place in the field of anthropological enquiry, and yet outwardly presenting such simplicity of form, offer a particular challenge to the radical, and in several recent works have been interpreted in what is claimed to be a novel and distinctive way.


Archaea ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-6
Author(s):  
Yanli Zhang ◽  
Linley R. Schofield ◽  
Carrie Sang ◽  
Debjit Dey ◽  
Ron S. Ronimus

(R)-Sulfolactate dehydrogenase (EC 1.1.1.337), termed ComC, is a member of an NADH/NADPH-dependent oxidoreductase family of enzymes that catalyze the interconversion of 2-hydroxyacids into their corresponding 2-oxoacids. The ComC reaction is reversible and in the biosynthetic direction causes the conversion of (R)-sulfolactate to sulfopyruvate in the production of coenzyme M (2-mercaptoethanesulfonic acid). Coenzyme M is an essential cofactor required for the production of methane by the methyl-coenzyme M reductase complex. ComC catalyzes the third step in the first established biosynthetic pathway of coenzyme M and is also involved in methanopterin biosynthesis. In this study, ComC fromMethanobrevibacter milleraeSM9 was cloned and expressed inEscherichia coliand biochemically characterized. Sulfopyruvate was the preferred substrate using the reduction reaction, with 31% activity seen for oxaloacetate and 0.2% seen forα-ketoglutarate. Optimal activity was observed at pH 6.5. The apparentKMfor coenzyme (NADH) was 55.1 μM, and for sulfopyruvate, it was 196 μM (for sulfopyruvate theVmaxwas 93.9 μmol min−1 mg−1andkcatwas 62.8 s−1). The critical role of ComC in two separate cofactor pathways makes this enzyme a potential means of developing methanogen-specific inhibitors for controlling ruminant methane emissions which are increasingly being recognized as contributing to climate change.


Author(s):  
Natalia S. Krelenko ◽  
Keyword(s):  

The article deals with the analysis of H. Walpole’s “Historic Doubts on the Life and Reign of King Richard the Third”. The focus of the article is on the attempt of reconsideration and rehabilitation of English king Richard III. An amateur historian and expert on the subtleties of politics, H. Walpole tried to establish a link between the development of the image of Richard III and political atmosphere prevailing in England after his death. Walpole’s work contains an interesting analysis of the views of the authors whose writings formed the basis of historical portrait of the last king of the House of York. It also contains a few remarks on the role and importance of history in society.


10.37236/2549 ◽  
2013 ◽  
Vol 20 (2) ◽  
Author(s):  
Hua Han ◽  
Zaiping Lu

In this paper, we investigate semisymmetric graphs which arise from affine primitive permutation groups. We give a characterization of such graphs, and then construct an infinite family of semisymmetric graphs which contains the Gray graph as the third smallest member. Then, as a consequence, we obtain a factorization,of the complete bipartite graph $K_{p^{sp^t},p^{sp^t}}$ into connected semisymmetric graphs, where $p$ is an prime, $1\le t\le s$ with $s\ge2$ while $p=2$.


Balcanica ◽  
2004 ◽  
pp. 51-70
Author(s):  
Ivan Jordovic

The Focus of this study is the standpoint of the play Sisyphus and critias the leader of the thirty towards the right of the stronger. this is a question of constant interest in scientific circles, since its answer can serve as the indicator of the influence this famous theory has had. this interest has been encouraged by the fact that critias? authorship of the play is questionable. however, the question of the author is not of primary importance for this article, because there are some arguments, among some well known ones, which were not considered and which Show that in this satire, regardless of the author and the purpose of this fragment, the right of the stronger is actually non-existant. the first argument to support this theory is that nomosphysis antithesis is nowhere explicitly mentioned although it is the crucial element of the right of the stronger. in addition there is no claim in the play that the exploitation of the strong by the week or by law accrued. the second argument is that despite the incapability of laws to prevent the secret injustice, they and their importance for the human society are depicted in a positive light. it should also be noted that, unlike callicles and glaucon, laws are created to stop the bad and not the good. the third argument is that the invention of religion is accepted as a positive achievement, which finally enables the overcoming of primeval times and lawlessness. the reflection of this argument is a positive characterization of the individual who invented the fear of gods. the fourth argument, which has not been taken into consideration so far is the way the supporters and opponents of lawlessness are described and marked as ????? and ?????? in the satire only physically strong are considered as strong as opposed to callicles, where they are also spiritually superior. intelectually superior in Sisyphus is the inventor of the fear of gods who is also in favor of law and order. the fact that the strong are described as kako? while the supporter of law are recognized as ?????? is also of great importance. in other words, this division re?ects strong influence of aristocratic set of values by which the ?????? are in every way superior to the ?????. some other indications Show that critias cannot be listed as a advocate of the right of the stronger regardless of our previous conclusion about the play. we need to bear in mind the fact that critias has only recently been linked with the theory of the right of the stronger. in the classical period there had been non attempt to explain his ruthless politics in Athens 404/403 BC by Means of the right of the stronger. what is more, no indication that he supported this theory were found. unlike xenophon and philostratus, it is very likely that Plato and Aristotle were mild to critias Due to his family ties with Plato and his friendship with Socrates. however, all the four of them would have stated that critias was an upholder of the right of the stronger if he had actually been that. that way Socrates would have been completely acquitted of the responsibility for the crimes critias had committed, because of the possible assertion that critias was misled by this theory and succumbed to the negative influence of the sophistic teachings. based on these arguments we can conclude that there is no trace of the right of the stronger in the play Sisyphus and that critias did not support this theory. this satirical play and critias were Most probably under a great influence of aristocratic beliefs, which were often scientifically misinterpreted as the reflection of the right of the stronger.


Sign in / Sign up

Export Citation Format

Share Document