Bibliographies thématiques / Soluble and nilpotent group

Littérature scientifique sur le sujet « Soluble and nilpotent group »

Auteur : Grafiati
Publié le 10 mars 2023

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Articles de revues sur le sujet "Soluble and nilpotent group"

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Burns, R. G., et Yuri Medvedev. « Group Laws Implying Virtual Nilpotence ». Journal of the Australian Mathematical Society 74, no 3 (juin 2003) : 295–312. http://dx.doi.org/10.1017/s1446788700003335.

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AbstractIf ω ≡ 1 is a group law implying virtual nilpotence in every finitely generated metabelian group satisfying it, then it implies virtual nilpotence for the finitely generated groups of a large class of groups including all residually or locally soluble-or-finite groups. In fact the groups of satisfying such a law are all nilpotent-by-finite exponent where the nilpotency class and exponent in question are both bounded above in terms of the length of ω alone. This yields a dichotomy for words. Finally, if the law ω ≡ 1 satisfies a certain additional condition—obtaining in particular for any monoidal or Engel law—then the conclusion extends to the much larger class consisting of all ‘locally graded’ groups.
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Amberg, Bernhard, Silvana Franciosi et Francesco de Giovanni. « Nilpotent-by-Noetherian Factorized Groups ». Canadian Mathematical Bulletin 32, no 4 (1 décembre 1989) : 391–403. http://dx.doi.org/10.4153/cmb-1989-057-8.

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AbstractIt is shown that a soluble-by-finite product G = AB of a nilpotent-by-noetherian group A and a noetherian group B is nilpotentby- noetherian. Moreover, a bound for the torsion-free rank of the Fitting factor group of G is given, in terms of the torsion-free rank of the Fitting factor group of A and the torsion-free rank of B.
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HU, BIN, JIANHONG HUANG et ALEXANDER N. SKIBA. « ON THE σ-NILPOTENT NORM AND THE σ-NILPOTENT LENGTH OF A FINITE GROUP ». Glasgow Mathematical Journal 63, no 1 (27 février 2020) : 121–32. http://dx.doi.org/10.1017/s0017089520000051.

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AbstractLet G be a finite group and σ = {σi| i ∈ I} some partition of the set of all primes $\Bbb{P}$ . Then G is said to be: σ-primary if G is a σi-group for some i; σ-nilpotent if G = G1× … × Gt for some σ-primary groups G1, … , Gt; σ-soluble if every chief factor of G is σ-primary. We use $G^{{\mathfrak{N}}_{\sigma}}$ to denote the σ-nilpotent residual of G, that is, the intersection of all normal subgroups N of G with σ-nilpotent quotient G/N. If G is σ-soluble, then the σ-nilpotent length (denoted by lσ (G)) of G is the length of the shortest normal chain of G with σ-nilpotent factors. Let Nσ (G) be the intersection of the normalizers of the σ-nilpotent residuals of all subgroups of G, that is, $${N_\sigma }(G) = \bigcap\limits_{H \le G} {{N_G}} ({H^{{_\sigma }}}).$$ Then the subgroup Nσ (G) is called the σ-nilpotent norm of G. We study the relationship of the σ-nilpotent length with the σ-nilpotent norm of G. In particular, we prove that the σ-nilpotent length of a σ-soluble group G is at most r (r > 1) if and only if lσ (G/ Nσ (G)) ≤ r.
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Shi, Jiangtao, et Cui Zhang. « A Note on TI-Subgroups of a Finite Group ». Algebra Colloquium 21, no 02 (11 avril 2014) : 343–46. http://dx.doi.org/10.1142/s1005386714000297.

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Let G be a finite group and H a subgroup of G. Recall that H is said to be a TI-subgroup of G if Hg∩ H = 1 or H for each g ∈ G. In this note, we prove that if all non-nilpotent subgroups of a finite non-nilpotent group G are TI-subgroups, then G is soluble, and all non-nilpotent subgroups of G are normal.
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Robinson, Derek J. S. « Soluble products of nilpotent groups ». Journal of Algebra 98, no 1 (janvier 1986) : 183–96. http://dx.doi.org/10.1016/0021-8693(86)90021-9.

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Smith, Howard. « Groups with few non-nilpotent subgroups ». Glasgow Mathematical Journal 39, no 2 (mai 1997) : 141–51. http://dx.doi.org/10.1017/s0017089500032031.

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Let G be a non-nilpotent group in which all proper subgroups are nilpotent. If G is finite then G is soluble [18], and a classification of such groups is given in [14]. The paper [12]. of Newman and Wiegold discusses infinite groups with this property. Clearly such a group is either finitely generated or locally nilpotent. Many interesting results concerning the finitely generated case are established in [12]. Since the publication of that paper there have appeared the examples due to Ol'shanskii and Rips (see [13]) of finitely generated infinite simple p-groups all of whose proper nontrivial subgroups have order p, a prime. Following [12], let us say that a group G is an AN-group if it is locally nilpotent and non-nilpotent with all proper subgroups nilpotent. A complete description is given in Section 4 of [12] of AN-groups having maximal subgroups. Every soluble AN-gvoup has locally cyclic derived factor group and is a p-group for some prime p ([12; Lemma 4.2]). The only further information provided in [12] on AN-groups without maximal subgroups is that they are countable. Four years or so after the publication of [12], there appeared the examples of Heineken and Mohamed [5]: for every prime p there exists a metabelian, non-nilpotent p-group G having all proper subgroups nilpotent and subnormal; further, G has no maximal subgroups and so G/G' is a Prüfer p-group in each case.
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Milliet, Cédric. « On the definability of radicals in supersimple groups ». Journal of Symbolic Logic 78, no 2 (juin 2013) : 649–56. http://dx.doi.org/10.2178/jsl.7802160.

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AbstractIf G is a group with a supersimple theory having a finite SU-rank, then the subgroup of G generated by all of its normal nilpotent subgroups is definable and nilpotent. This answers a question asked by Elwes, Jaligot, Macpherson and Ryten. If H is any group with a supersimple theory, then the subgroup of H generated by all of its normal soluble subgroups is definable and soluble.
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Franciosi, Silvana, Francesco de Giovanni et Yaroslav P. Sysak. « An extension of the Kegel–Wielandt theorem to locally finite groups ». Glasgow Mathematical Journal 38, no 2 (mai 1996) : 171–76. http://dx.doi.org/10.1017/s0017089500031402.

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A famous theorem of Kegel and Wielandt states that every finite group which is the product of two nilpotent subgroups is soluble (see [1], Theorem 2.4.3). On the other hand, it is an open question whether an arbitrary group factorized by two nilpotent subgroups satisfies some solubility condition, and only a few partial results are known on this subject. In particular, Kegel [6] obtained an affirmative answer in the case of linear groups, and in the same article he also proved that every locally finite group which is the product of two locally nilpotent FC-subgroups is locally soluble. Recall that a group G is said to be an FC-group if every element of G has only finitely many conjugates. Moreover, Kazarin [5] showed that if the locally finite group G = AB is factorized by an abelian subgroup A and a locally nilpotent subgroup B, then G is locally soluble. The aim of this article is to prove the following extension of the Kegel–Wielandt theorem to locally finite products of hypercentral groups.
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Franciosi, Silvana, et Francesco de Giovanni. « On the Hirsch-Plotkin radical of a factorized group ». Glasgow Mathematical Journal 34, no 2 (mai 1992) : 193–99. http://dx.doi.org/10.1017/s0017089500008715.

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Let the group G = AB be the product of two subgroups A and B. A normal subgroup K of G is said to be factorized if K = (A ∩ K)(B ∩ K) and A ∩ B ≤ K, and this is well-known to be equivalent to the fact that K = AK ∩ BK (see [1]). Easy examples show that normal subgroups of a product of two groups need not, in general, be factorized. Therefore the determination of certain special factorized subgroups is of relevant interest in the investigation concerning the structure of a factorized group. In this direction E. Pennington [5] proved that the Fitting subgroup of a finite product of two nilpotent groups is factorized. This result was extended to infinite groups by B. Amberg and theauthors, who provedin [2] that if the soluble group G = AB with finite abelian section rank isthe product of two locally nilpotent subgroups A and B, then the Hirsch-Plotkin radical (i.e. the maximum locally nilpotent normal subgroup) of G is factorized. If G is a soluble ℒI group and the factors A and B are nilpotent, it was shown in [3] that also the Fitting subgroup of G is factorized. However, Pennington's theorem becomes false for finite soluble groups which are the productof two arbitrary subgroups. For instance, the symmetric group of degree 4 is the product of a subgroup isomorphic with the symmetric group of degree 3 and a cyclic subgroup of order 4, but its Fitting subgroup is not factorized.
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Taeri, Bijan. « A question of Paul Erdös and nilpotent-by-finite groups ». Bulletin of the Australian Mathematical Society 64, no 2 (octobre 2001) : 245–54. http://dx.doi.org/10.1017/s0004972700039903.

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Let n be a positive integer or infinity (denoted ∞), k a positive integer. We denote by Ωk(n) the class of groups G such that, for every subset X of G of cardinality n + 1, there exist distinct elements x, y ∈ X and integers t0, t1…, tk such that , where xi, ∈ {x, y}, i = 0, 1,…,k, x0 ≠ x1. If the integers t0, t1,…,tk are the same for any subset X of G, we say that G is in the class Ω̅k(n). The class k (n) is defined exactly as Ωk(n) with the additional conditions . Let t2, t3,…,tk be fixed integers. We denote by the class of all groups G such that for any infinite subsets X and Y there exist x ∈ X, y ∈ Y such that , where xi ∈ {x, y}, x0 ≠ x1, i = 2, 3, …, k. Here we prove that (1) If G ∈ k(2) is a finitely generated soluble group, then G is nilpotent.(2) If G ∈ Ωk(∞) is a finitely generated soluble group, then G is nilpotentby-finite.(3) If G ∈ Ω̅k(n), n a positive integer, is a finitely generated residually finite group, then G is nilpotent-by-finite.(4) If G is an infinite -group in which every nontrivial finitely generated subgroup has a nontrivial finite quotient, then G is nilpotent-by-finite.
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Thèses sur le sujet "Soluble and nilpotent group"

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Wharton, Elizabeth. « The model theory of certain infinite soluble groups ». Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:7bd8d05b-4ff6-4326-8463-f896e2862e25.

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This thesis is concerned with aspects of the model theory of infinite soluble groups. The results proved lie on the border between group theory and model theory: the questions asked are of a model-theoretic nature but the techniques used are mainly group-theoretic in character. We present a characterization of those groups contained in the universal closure of a restricted wreath product U wr G, where U is an abelian group of zero or finite square-free exponent and G is a torsion-free soluble group with a bound on the class of its nilpotent subgroups. For certain choices of G we are able to use this characterization to prove further results about these groups; in particular, results related to the decidability of their universal theories. The latter part of this work consists of a number of independent but related topics. We show that if G is a finitely generated abelian-by-metanilpotent group and H is elementarily equivalent to G then the subgroups gamma_n(G) and gamma_n(H) are elementarily equivalent, as are the quotient groups G/gamma_n(G) and G/gamma_n(H). We go on to consider those groups universally equivalent to F_2(VN_c), where the free groups of the variety V are residually finite p-groups for infinitely many primes p, distinguishing between the cases when c = 1 and when c > 2. Finally, we address some important questions concerning the theories of free groups in product varieties V_k · · ·V_1, where V_i is a nilpotent variety whose free groups are torsion-free; in particular we address questions about the decidability of the elementary and universal theories of such groups. Results mentioned in both of the previous two paragraphs have applications here.
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Grenham, Dermot. « Some topics in nilpotent group theory ». Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329954.

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Smith, Jeremy Francis. « Topics in products of nilpotent groups ». Thesis, University of Warwick, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340502.

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Popov, Vladimir L., et popov@ppc msk ru. « Self-Dual Algebraic Varieties and Nilpotent Orbits ». ESI preprints, 2001. ftp://ftp.esi.ac.at/pub/Preprints/esi978.ps.

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Budde, Julia [Verfasser]. « Wave front sets of nilpotent lie group representations / Julia Budde ». Paderborn : Universitätsbibliothek, 2021. http://d-nb.info/122950415X/34.

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Sohrabi, Mahmood. « Groups elementary equivalent to a free 2-nilpotent group of arbitrary finite rank ». Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98801.

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In this thesis we discuss the characterization of groups elementary equivalent to a free 2-nilpotent group G of arbitrary finite rank. We find a characterization and verify it using two different lines of argument. The first one goes through using a construction very similar to the famous Mal'cev correspondence. This strategy is very much in the same spirit as the work of O. V. Belegradek on unitriangular groups. The second method, we call the method of bilinear mappings, is due to Alexei Miasnikov. A bilinear map fG is associated to the nilpotent group G. Then a commutative associative ring P(fG) is recovered via the bilinear mapping fG. This ring is the maximal ring relative to which fG remains bilinear. Under some reasonable conditions the ring P( fG) is absolutely interpretable in G. Then we use this construction to give a second proof for the characterization.
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Gjerling, Andreas. « On rings of quotients of soluble group algebras ». Thesis, Queen Mary, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286813.

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Harkins, Andrew. « Combining lattices of soluble lie groups ». Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341777.

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Uemura, Hideaki. « Off-Diagonal Short Time Expansion of the Heat Kernel on a Certain Nilpotent Lie Group ». 京都大学 (Kyoto University), 1989. http://hdl.handle.net/2433/86399.

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Salminen, Adam D. « On the sources of simple modules in nilpotent blocks ». Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1124221435.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains viii, 87 p. Includes bibliographical references (p. 85-87). Available online via OhioLINK's ETD Center
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Livres sur le sujet "Soluble and nilpotent group"

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Khukhro, Evgenii I. Nilpotent groups and their automorphisms. Berlin : W. de Gruyter, 1993.

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Harmonic analysis on the Heisenberg group. Boston : Birkhauser, 1998.

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1959-, McGovern William M., dir. Nilpotent orbits in semisimple Lie algebras. New York : Van Nostrand Reinhold, 1993.

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Schempp, W. Harmonic analysis on the Heisenberg nilpotent Lie group, with applications to signal theory. Harlow : Longman Scientific & Technical, 1986.

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Harmonic analysis on the Heisenberg nilpotent Lie group, with applications to signal theory. Harlow, Essex, England : Longman Scientific & Technical, 1986.

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Wilde, Thomas Stephen. Cohomology and the subgroup structure of a finite soluble group. [s.l.] : typescript, 1992.

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Meldrum, J. D. P. Wreath products of groups and semigroups. Harlow, Essex, England : Longman, 1995.

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The primitive soluble permutation groups of degree less than 256. Berlin : Springer-Verlag, 1992.

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1943-, Seitz Gary M., dir. Unipotent and nilpotent classes in simple algebraic groups and lie algebras. Providence, R.I : American Mathematical Society, 2012.

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Cazzola, Marina. Local character degrees and the derived length of a finite soluble group. [s.l.] : typescript, 1995.

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Chapitres de livres sur le sujet "Soluble and nilpotent group"

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Robinson, Derek J. S. « Soluble and Nilpotent Groups ». Dans A Course in the Theory of Groups, 121–58. New York, NY : Springer New York, 1996. http://dx.doi.org/10.1007/978-1-4419-8594-1_5.

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Robinson, Derek J. S. « Soluble and Nilpotent Groups ». Dans A Course in the Theory of Groups, 117–52. New York, NY : Springer US, 1993. http://dx.doi.org/10.1007/978-1-4684-0128-8_5.

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Robinson, Derek J. S. « Generalizations of Nilpotent and Soluble Groups ». Dans A Course in the Theory of Groups, 356–84. New York, NY : Springer New York, 1996. http://dx.doi.org/10.1007/978-1-4419-8594-1_12.

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Lennox, John C. « Soluble groups with nilpotent-extensible subgroups ». Dans Lecture Notes in Mathematics, 103–6. Berlin, Heidelberg : Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/bfb0078694.

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Robinson, Derek J. S. « Generalizations of Nilpotent and Soluble Groups ». Dans A Course in the Theory of Groups, 342–70. New York, NY : Springer US, 1993. http://dx.doi.org/10.1007/978-1-4684-0128-8_12.

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Roman, Steven. « Solvable and Nilpotent Groups ». Dans Fundamentals of Group Theory, 291–317. Boston : Birkhäuser Boston, 2011. http://dx.doi.org/10.1007/978-0-8176-8301-6_11.

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N. Mordeson, John, Kiran R. Bhutani et Azriel Rosenfeld. « Nilpotent, Commutator, and Solvable Fuzzy Subgroups ». Dans Fuzzy Group Theory, 61–89. Berlin, Heidelberg : Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/10936443_3.

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Eckmann, Beno. « Nilpotent group action and Euler characteristic ». Dans Algebraic Topology Barcelona 1986, 120–23. Berlin, Heidelberg : Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/bfb0083004.

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Auslander, L., et R. Tolimieri. « Lectures on Nilpotent Groups and Abelian Varieties ». Dans Harmonic Analysis and Group Representation, 6–47. Berlin, Heidelberg : Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-11117-4_1.

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Wehrfritz, B. A. F. « Soluble Linear Groups ». Dans Group and Ring Theoretic Properties of Polycyclic Groups, 41–54. London : Springer London, 2009. http://dx.doi.org/10.1007/978-1-84882-941-1_4.

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Actes de conférences sur le sujet "Soluble and nilpotent group"

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NOUMI, MASATOSHI, et YASUHIKO YAMADA. « BIRATIONAL WEYL GROUP ACTION ARISING FROM A NILPOTENT POISSON ALGEBRA ». Dans Proceedings of the Nagoya 1999 International Workshop. WORLD SCIENTIFIC, 2001. http://dx.doi.org/10.1142/9789812810199_0010.

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Zhang, Lifu, Mike Tice, Franco Marcantonio et Berna Hascakir. « Solid and Soluble Products of Engineered Water/Rock Interactions in Eagle Ford Group Chemofacies ». Dans SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 2017. http://dx.doi.org/10.2118/187296-ms.

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Markovic, Maja, Vesna Panic, Julijana Tadic et Rada Pjanovic. « EFFECT OF CROSSLINKER AMOUNT ON HYBRID HYDROGELS SWELLING AND DRUG RELEASE ». Dans 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac, 2021. http://dx.doi.org/10.46793/iccbi21.125m.

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Targeted drug delivery is powerful tool which researchers use to achieve safer and more efficient therapy of many diseases, including various types of cancer. Many chemotherapeutics are poorly water- soluble, so their encapsulation and targeted delivery remain quite challenge. Hydrogels based on poly(methacrylic acid) (PMAA) are widely investigated for targeted drug delivery due to their pH sensitivity, non-toxicity and biocompatibility. Still, due to the PMAA highly hydrophilic nature, PMAA can only be used for encapsulation and targeted delivery of water-soluble drugs. Our previous research was directed towards overcoming this limitation: PMAA was modified with amphiphilic protein – casein and poorly-water soluble model drug – caffeine – was encapsulated (PMAC). Present study is focused on investigation how variation of amount of one of the most important hydrogels network parameter such as crosslinker affect PMAC swelling properties and caffeine release. The group of hybrid hydrogels – PMAC – was synthesized with various amount of crosslinker: 0.4mol%, 0.8mol%, 1.6mol% and 3.2mol% with respect to methacrylic acid. Swelling behavior of hybrid hydrogels and caffeine release was investigated in two environments which simulated human stomach and intestines. Obtained results showed that targeted delivery of poorly water-soluble model drug was achieved and that its release can be prolonged up to 24h. Also, kinetic of poorly water-soluble drug release can be easily modified only by changing crosslinker amount. PMAC hybrid hydrogels have huge potential for targeted delivery of poorly water-soluble active substances.
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Carr, JM, ML McKinney, I. Neuringer et J. McDonagh. « MONOCLONAL ANTIBODIES To D-DIMER : DISCREPANT LATEX AGGLUTINATION AND EIA RESULTS IN LIVER DISEASE PATIENTS ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644836.

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Measurement of fibrin (ogen) degradation products (FDP) by latex agglutination with polyclonal antifibrinogen may be falsely elevated in liver disease due to the presence of “poorly clottable” fibrinogen in serum (Blood 67:1468, 1986). TSro monoclonal antibodies recognizing different epitopes of fibrin degradation fragment D-dimer (DD) are now commercially available. Because of the reported lack of crossreactivity of the DD monoclonals with fibrinogen, we employed them as tools to distinguish true fibrinolysis from false positive results due to liver disease. 17 citrated plasmas were evaluated by 5%SDS PAGE, nitrocellulose transfer and polyclonal antifibrinogen blotting for detection of FDP (X,ED,Y,D). Samples were then evaluated for ED by latex agglutination and by EIA (enzyme immunoassay) with the following results:Patients in Groups 3a and 3b were jaundiced (bilirubins 3.2-27) and had either hepatitis or cirrhosis except for one patient in Group 3a who had metastatic cancer. Assay for soluble fibrin monomer (SFM) by hemagglutination was negative in group 3b but positive in 5 of 7 patients in group 3a. Neither eta recognized fibrinogen. Purified fibrin monomer gave positive results with both EIAs. Detection of fibrinolysis by latex agglutination using monoclonal anti-DD resolves the problem of false positive results seen with polyclonal antifibrinogen in patients with liver disease. Elevated SFM in the absence of disseminated intravascular coagulation (DIC) in patients with liver disease may induce false positive ED results when measured by EIA.
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Khan, Suhail Ahmad, V. Jagannathan et R. P. Jain. « IAEA CRP Benchmark of Kalinin VVER-1000 NPP : An Analysis Using EXCEL-TRIHEX-FA Code System ». Dans 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48613.

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Two units of VVER-1000Mwe reactors are in an advanced stage of construction at Kudankulam, Tamilnadu, India. With a view to assess the capability of analyzing the physics characteristics of VVER cores, the IAEA CRP benchmark problem of Kalinin VVER-1000 MWe NPP [1] is studied using the indigenous code system EXCEL-TRIHEX-FA [2,3]. The lattice burnup code EXCEL is based on a combination of 1-D multigroup transport theory and 2-D few group diffusion theory. Nuclear data in 172 group WIMS-D format based on JEFF-3.1 [4] has been used in the present analysis. The core level calculations are performed using the code TRIHEX-FA which solves the 3-D multigroup diffusion equation using the finite difference method with fine triangular meshes. Power dependent feedback models for xenon, Doppler, coolant temperature and density values have been incorporated in TRIHEX-FA. Keff for the critical soluble boron concentration, assembly power distribution and axial power distribution are calculated as a function of fuel cycle burnup. In the present paper, lattice level results are compared with the results of other participants reported in Ref. [1]. The results of core level calculations have been compared with the experimental data provided [1].
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6

Looten, Kristopher A., et Mustansar Raza. « Temporary Isolation of a Prolific Open Hole Gas Zone using a Non-Damaging Methodology - A Multi-Well Case Study in a Field of Kurdistan N. Iraq ». Dans SPE/IADC Middle East Drilling Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/202074-ms.

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Abstract Objectives/Scope A case study is presented detailing the methodology used to place a non-damaging temporary isolation barrier in a group of naturally fractured, prolific gas wells in a field in Kurdistan. The temporary isolation facilitated removal of the original completion string and installation of the redesign. Wells were returned to production with-out the need to stimulate proving success of the non-damaging methodology employed. Methods, Procedures, Process The operator had 4 wells with OH sections ranging from 33-181m which were completed in the 1980’s - 1990's with no production packer. In order to preserve well bore integrity the completion string needed to be pulled and replaced by a string with production packer and DH gauges. A procedure was developed to fill the highly fractured OH with a mixed particle size CaCO3 carried into the wellbore by a non-damaging surfactant based gel. Caliper logs were not available and the presence of natural fractures posed a challenge to calculating the actual OH volume. A system was developed to carry the CaCO3 into the wellbore in stages and slickline was employed to measure fill after each stage. Once the OH was filled with CaCO3 and well would support a fluid column coil tubing was used to place an acid soluble cement plug in the short interval between casing shoe and end of tubing (8-10m) Results, Observations, Conclusions The first well in the campaign required more than 10 times the theoretical volume of CaCO3 to fill the open hole. It was concluded the surfactant gel was likely carrying the CaCO3 into the fractures. The procedure was modified to tie in a line of breaker solution to the well head allowing sufficient viscosity of the fluid to carry the CaCO3 from surface but immediately lose viscosity and allow the CaCO3 to settle in the wellbore without being carried into the formation. Specific coil tubing procedures were employed to allow the setting of ultra-short acid soluble cement plugs (<10m). All wells were successfully isolated to allow the safe workover of the completion string and returned to production with no loss of gas flow, with-out the need to stimulate after the work over. Novel/Additive Information The campaign exhibited a new method of employing existing technologies to achieve the objective in a highly challenging and relatively new oilfield of Kurdistan. The campaign also demonstrated the benefit of the operator and service company closely collaborating on each step of a novel process. The workovers would not have been successful with-out the close collaboration of the two companies.
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7

Mysliwiec, M., D. Alderson, L. Poller et P. Ackrill. « PROTEIN C AND OTHER CLOTTING STUDIES IN MEMBRANOUS AND NON-MEMBRANOUS GLOMERULONEPHRITIS ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644310.

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The occurrence of thrombosis in the nephrotic syn drome has long been known. Thrombotic complications are predominantly associated with membranous glomerulonephritis (MG). The aim of the present work was to study whether the tendency of nephrotic patients with MG to thrombotic episodes could be attributed to a hypercoagulable state. Thirty consecutive patients with the nephrotic syndrome were studied. Of these 17 suffered from MG and 13 had other forms of glomerulonephritis. The control group consisted of 10 healthy volunteers. In addition to standard coagulation assays, we studied: soluble fibrin monomer complexes (FM test, Boehringer), fibrin monomer polymerization, factor VIII:C, factor VIII:vWF, anti thrombin III (AT III) and alpha2 antiplasmin (alpha2AP) using chromogenie substrates; the levels of AT III and alpha2 AP were measured immunologically; beta thromboglobulin (BTG), platelet factor 4 and fibrinopeptide A (FPA) using radioimmunoassay kits; protein C was studied functionally and immunologically. There was a significant shortening of the prothrombin time and activated partial thromboplastin time, increase in alpha9 AP, factor V111:vWF, FPA and BTG in nephrotic patients associated with in or eases in both functional and imminclogical protein C levels and impairment of fibrin polymerization. FM test was negative in all but one of the patients. None of the coagulation tests showed a significant difference in the two nephrotic groups. High protein C and impaired polymerization may be considered as mechanisms counteracting disclosed hypercoagulability in the nephrotic syndrome.
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Tartis, Michaelann S., Jan Marik, Azadeh Kheirolomoom, Rachel E. Pollard, Hua Zhang, Jinyi Qi, Julie L. Sutcliffe et Katherine W. Ferrara. « Pharmacokinetics of Encapsulated Paclitaxel : Multi-Probe Analysis With PET ». Dans ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-176435.

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We have combined two imaging probes and used PET as a means to provide image-based validation for a novel targeted drug delivery system. The first probe was a direct labeling of the drug [18F]fluoropaclitaxel [1–3], which was inserted into various carrier vehicle formulations. The second probe, [18F]fluoro-1,2-dipalmitoyl-sn-glycerol, i.e. [18F]FDP involved radiolabeling the lipid vehicle. Paclitaxel, which is poorly soluble in aqueous media, also has limited solubility and stability in lipophilic environments such as liposomes. Stable association of paclitaxel with the lipid bilayer is affected by a variety of physicochemical factors such as temperature and liposome composition. Paclitaxel crystal formation has been documented, with two forms of solid state within aqueous media and organic solvents, although crystal conformation differs in each media [4,5]. We provide dynamic in vivo image sets providing biodistribution and time activity curves of free [18F]fluoropaclitaxel and liposomal [18F]fluoropaclitaxel as well as free [18F]FDP, liposomal [18F]FDP, and [18F]FDP in an ultrasound contrast agent. Serial studies were performed within a small group of rats, minimizing inter-animal variability. The two labeled molecules have different biodistributions: paclitaxel is rapidly taken up in the liver, intestines and kidneys, while the labeled lipid incorporated into liposomes stays in circulation with minimal uptake in organs other than spleen. Here, we have developed a quantitative method to follow paclitaxel and lipid vehicles to their destination in vivo in order to improve targeted paclitaxel delivery.
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Spears, Terrel J., James W. McCullough, Harry D. Harmon et Robert K. Leugemors. « Status of the Salt Waste Processing Facility at the Savannah River Site ». Dans ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4651.

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The Department of Energy’s (DOE) Savannah River Site (SRS) High-Level Waste (HLW) Program is responsible for storage, treatment, and immobilization of HLW for disposal. The Salt Processing Program (SPP) is the salt (soluble) waste treatment portion of this effort. The overall SPP encompasses the selection, design, construction and operation of treatment technologies to prepare the salt waste feed material for the site’s Saltstone Facility and vitrification facility (Defense Waste Processing Facility). Major constituents that must be removed from the salt waste include actinides, strontium, cesium, and entrained sludge. In fiscal year (FY) 2002, research and development (R&D) on the actinide and strontium removal and Caustic-Side Solvent Extraction (CSSX) processes transitioned from technology development for baseline process selection to providing input for conceptual design of the Salt Waste Processing Facility (SWPF), a key component at the SRS SPP. This work included laboratory studies, bench-scale tests, and prototype equipment development. To implement the salt waste treatment technologies, DOE initiated a competitive procurement process to select Engineering, Procurement, and Construction (EPC) contractors for design of the SWPF. The Department awarded EPC contracts to Parsons Infrastructure & Technology Group, Inc. and Foster Wheeler USA Corporation for preparation of conceptual designs (Phase I) for the SWPF. The two EPC contractors began conceptual design activities in September 2002 and are scheduled to complete this work in January 2004. After evaluation of the conceptual designs, DOE will down select one EPC contractor to continue with final design, construction, and hot commissioning (Phase II). Hot startup of the SWPF is targeted for December 2009.
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Raza, Mustansar, Hossam Elmoneim, Kris Looten, Omar Elzanaty, Ahmed Shakeel, Kamil Shehzad, Mustafa Sarbast et Serwer Yousif. « Making Workovers Easy and Cost Effective : Turning Old Ways into New Opportunities ». Dans SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206086-ms.

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Abstract A case study and methodology is presented to shed the light on the different processes followed during the placement of a non-damaging isolation barrier in a group of highly naturally-fractured and vugular gas wells. The temporary isolation aims at isolating the wellbore from the troublesome formation and allow the removal of the original completion string and install a new redesigned one. The process helped putting the wells back on production with-out the need to stimulate any of them. This helped client to reduce the overall workover cost by 40% and proved to be successful and efficient to complete the required operation in a time-efficient. The operator had 4 wells with OH sections ranging from 40-80m which were completed in the late 1990's with no production packer. To preserve wellbore integrity the completion string needed to be pulled and replaced by a string with production packer and DH gauges. Visco-Elastic Surfactant (VES) and calcium CaCO3 (carbonate) used ubiquitously in field operations were tested for optimal design to fill highly fractured OH without damaging formation. Caliper logs were not available, and the presence of natural fractures posed a challenge to calculate the actual OH volume. A system was developed to carry the CaCO3 into the wellbore in stages and slickline was employed to measure fill after each stage. Once the OH was filled with CaCO3 and well would support a fluid column coil tubing was used to place an acid-soluble cement plug in the short interval between casing shoe and end of tubing (6-9m). The paper describes the optimization process followed to tune the CaCO3 pads composition, gel composition, mixing and placement technique. The first well in the campaign required more than 10 times the theoretical volume of CaCO3 to fill the open hole with multiple settling issues at surface. It was concluded the surfactant gel was likely carrying the CaCO3 into the fractures. The procedure was modified to tie in a line of breaker solution to the well head allowing sufficient viscosity of the fluid to carry the CaCO3 from surface but immediately lose viscosity and allow the CaCO3 to settle in the open hole without being carried into the formation. Specific coil tubing procedures were employed to allow the setting of ultra-short acid soluble cement plugs (<6m). All wells were successfully isolated to allow the safe workover of the completion string and returned to production with no loss of gas flow, with-out the need to stimulate after the work over. The campaign exhibited a new method of employing existing technologies to achieve the objective in a highly challenging and relatively new oilfield of Kurdistan. The campaign also demonstrated the benefit, in terms of saving time and cost because of extensive pre-execution planning.
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Rapports d'organisations sur le sujet "Soluble and nilpotent group"

1

Shenker, Moshe, Paul R. Bloom, Abraham Shaviv, Adina Paytan, Barbara J. Cade-Menun, Yona Chen et Jorge Tarchitzky. Fate of Phosphorus Originated from Treated Wastewater and Biosolids in Soils : Speciation, Transport, and Accumulation. United States Department of Agriculture, juin 2011. http://dx.doi.org/10.32747/2011.7697103.bard.

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Beneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levelsBeneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levels that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction.
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2

Shpigel, Nahum Y., Ynte Schukken et Ilan Rosenshine. Identification of genes involved in virulence of Escherichia coli mastitis by signature tagged mutagenesis. United States Department of Agriculture, janvier 2014. http://dx.doi.org/10.32747/2014.7699853.bard.

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Mastitis, an inflammatory response of the mammary tissue to invading pathogenic bacteria, is the largest health problem in the dairy industry and is responsible for multibillion dollar economic losses. E. coli are a leading cause of acute mastitis in dairy animals worldwide and certainly in Israel and North America. The species E. coli comprises a highly heterogeneous group of pathogens, some of which are commensal residents of the gut, infecting the mammary gland after contamination of the teat skin from the environment. As compared to other gut microflora, mammary pathogenic E. coli (MPEC) may have undergone evolutionary adaptations that improve their fitness for colonization of the unique and varied environmental niches found within the mammary gland. These niches include competing microbes already present or accompanying the new colonizer, soluble and cellular antimicrobials in milk, and the innate immune response elicited by mammary cells and recruited immune cells. However, to date, no specific virulence factors have been identified in E. coli isolates associated with mastitis. The original overall research objective of this application was to develop a genome-wide, transposon-tagged mutant collection of MPEC strain P4 and to use this technology to identify E. coli genes that are specifically involved in mammary virulence and pathogenicity. In the course of the project we decided to take an alternative genome-wide approach and to use whole genomes bioinformatics analysis. Using genome sequencing and analysis of six MPEC strains, our studies have shown that type VI secretion system (T6SS) gene clusters were present in all these strains. Furthermore, using unbiased screening of MPEC strains for reduced colonization, fitness and virulence in the murine mastitis model, we have identified in MPEC P4-NR a new pathogenicity island (PAI-1) encoding the core components of T6SS and its hallmark effectors Hcp, VgrG and Rhs. Next, we have shown that specific deletions of T6SS genes reduced colonization, fitness and virulence in lactating mouse mammary glands. Our long-term goal is to understand the molecular mechanisms of host-pathogen interactions in the mammary gland and to relate these mechanisms to disease processes and pathogenesis. We have been able to achieve our research objectives to identify E. coli genes that are specifically involved in mammary virulence and pathogenicity. The project elucidated a new basic concept in host pathogen interaction of MPEC, which for the best of our knowledge was never described or investigated before. This research will help us to shed new light on principles behind the infection strategy of MPEC. The new targets now enable prevalence and epidemiology studies of T6SS in field strains of MPEC which might unveil new geographic, management and ecological risk factors. These will contribute to development of new approaches to treat and prevent mastitis by MPEC and perhaps other mammary pathogens. The use of antibiotics in farm animals and specifically to treat mastitis is gradually precluded and thus new treatment and prevention strategies are needed. Effective mastitis vaccines are currently not available, structural components and effectors of T6SS might be new targets for the development of novel vaccines and therapeutics.
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3

Epel, Bernard, et Roger Beachy. Mechanisms of intra- and intercellular targeting and movement of tobacco mosaic virus. United States Department of Agriculture, novembre 2005. http://dx.doi.org/10.32747/2005.7695874.bard.

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To cause disease, plant viruses must replicate and spread locally and systemically within the host. Cell-to-cell virus spread is mediated by virus-encoded movement proteins (MPs), which modify the structure and function of plasmodesmata (Pd), trans-wall co-axial membranous tunnels that interconnect the cytoplasm of neighboring cells. Tobacco mosaic virus (TMV) employ a single MP for cell- cell spread and for which CP is not required. The PIs, Beachy (USA) and Epel (Israel) and co-workers, developed new tools and approaches for study of the mechanism of spread of TMV that lead to a partial identification and molecular characterization of the cellular machinery involved in the trafficking process. Original research objectives: Based on our data and those of others, we proposed a working model of plant viral spread. Our model stated that MPᵀᴹⱽ, an integral ER membrane protein with its C-terminus exposed to the cytoplasm (Reichel and Beachy, 1998), alters the Pd SEL, causes the Pd cytoplasmic annulus to dilate (Wolf et al., 1989), allowing ER to glide through Pd and that this gliding is cytoskeleton mediated. The model claimed that in absence of MP, the ER in Pd (the desmotubule) is stationary, i.e. does not move through the Pd. Based on this model we designed a series of experiments to test the following questions: -Does MP potentiate ER movement through the Pd? - In the presence of MP, is there communication between adjacent cells via ER lumen? -Does MP potentiate the movement of cytoskeletal elements cell to cell? -Is MP required for cell-to-cell movement of ER membranes between cells in sink tissue? -Is the binding in situ of MP to RNA specific to vRNA sequences or is it nonspecific as measured in vitro? And if specific: -What sequences of RNA are involved in binding to MP? And finally, what host proteins are associated with MP during intracellular targeting to various subcellular targets and what if any post-translational modifications occur to MP, other than phosphorylation (Kawakami et al., 1999)? Major conclusions, solutions and achievements. A new quantitative tool was developed to measure the "coefficient of conductivity" of Pd to cytoplasmic soluble proteins. Employing this tool, we measured changes in Pd conductivity in epidermal cells of sink and source leaves of wild-type and transgenic Nicotiana benthamiana (N. benthamiana) plants expressing MPᵀᴹⱽ incubated both in dark and light and at 16 and 25 ᵒC (Liarzi and Epel, 2005 (appendix 1). To test our model we measured the effect of the presence of MP on cell-to-cell spread of a cytoplasmic fluorescent probe, of two ER intrinsic membrane protein-probes and two ER lumen protein-probes fused to GFP. The effect of a mutant virus that is incapable of cell-to-cell spread on the spread of these probes was also determined. Our data shows that MP reduces SEL for cytoplasmic molecules, dilates the desmotubule allowing cell-cell diffusion of proteins via the desmotubule lumen and reduces the rate of spread of the ER membrane probes. Replicase was shown to enhance cell-cell spread. The data are not in support of the proposed model and have led us to propose a new model for virus cell-cell spread: this model proposes that MP, an integral ER membrane protein, forms a MP:vRNAER complex and that this ER-membrane complex diffuses in the lipid milieu of the ER into the desmotubule (the ER within the Pd), and spreads cell to cell by simple diffusion in the ER/desmotubule membrane; the driving force for spread is the chemical potential gradient between an infected cell and contingent non-infected neighbors. Our data also suggests that the virus replicase has a function in altering the Pd conductivity. Transgenic plant lines that express the MP gene of the Cg tobamovirus fused to YFP under the control the ecdysone receptor and methoxyfenocide ligand were generated by the Beachy group and the expression pattern and the timing and targeting patterns were determined. A vector expressing this MPs was also developed for use by the Epel lab . The transgenic lines are being used to identify and isolate host genes that are required for cell-to-cell movement of TMV/tobamoviruses. This line is now being grown and to be employed in proteomic studies which will commence November 2005. T-DNA insertion mutagenesis is being developed to identify and isolate host genes required for cell-to-cell movement of TMV.
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