Articles de revues : « Secant variety »

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Vermeire, Peter. « Singularities of the secant variety ». Journal of Pure and Applied Algebra 213, n^o 6 (juin 2009) : 1129–32. http://dx.doi.org/10.1016/j.jpaa.2008.11.006.

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Buczyński, Jarosław, et J. M. Landsberg. « On the third secant variety ». Journal of Algebraic Combinatorics 40, n^o 2 (16 janvier 2014) : 475–502. http://dx.doi.org/10.1007/s10801-013-0495-0.

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BUCZYŃSKA, WERONIKA, et JAROSŁAW BUCZYŃSKI. « ON DIFFERENCES BETWEEN THE BORDER RANK AND THE SMOOTHABLE RANK OF A POLYNOMIAL ». Glasgow Mathematical Journal 57, n^o 2 (17 décembre 2014) : 401–13. http://dx.doi.org/10.1017/s0017089514000378.

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AbstractWe consider higher secant varieties to Veronese varieties. Most points on the rth secant variety are represented by a finite scheme of length r contained in the Veronese variety – in fact, for a general point, the scheme is just a union of r distinct points. A modern way to phrase it is: the smoothable rank is equal to the border rank for most polynomials. This property is very useful for studying secant varieties, especially, whenever the smoothable rank is equal to the border rank for all points of the secant variety in question. In this note, we investigate those special points for which the smoothable rank is not equal to the border rank. In particular, we show an explicit example of a cubic in five variables with border rank 5 and smoothable rank 6. We also prove that all cubics in at most four variables have the smoothable rank equal to the border rank.

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Torrance, Douglas A. « Generic forms of low Chow rank ». Journal of Algebra and Its Applications 16, n^o 03 (mars 2017) : 1750047. http://dx.doi.org/10.1142/s0219498817500475.

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The least number of products of linear forms that may be added together to obtain a given form is the Chow rank of this form. The Chow rank of a generic form corresponds to the smallest [Formula: see text] for which the [Formula: see text]th secant variety of the Chow variety fills the ambient space. We show that, except for certain known exceptions, this secant variety has the expected dimension for low values of [Formula: see text].

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Sidman, Jessica, et Peter Vermeire. « Syzygies of the secant variety of a curve ». Algebra & ; Number Theory 3, n^o 4 (15 juin 2009) : 445–65. http://dx.doi.org/10.2140/ant.2009.3.445.

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Ugaglia, Luca. « SUBVARIETIES OF THE GRASSMANNIAN WITH SMALL SECANT VARIETY ». Communications in Algebra 30, n^o 8 (28 août 2002) : 4059–83. http://dx.doi.org/10.1081/agb-120005836.

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Shin, Yong-Su. « SECANT VARIETIES TO THE VARIETY OF REDUCIBLE FORMS ». Journal of the Chungcheong Mathematical Society 27, n^o 1 (15 février 2014) : 39–46. http://dx.doi.org/10.14403/jcms.2014.27.1.39.

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Abrescia, Silvia. « About the Defectivity of Certain Segre–Veronese Varieties ». Canadian Journal of Mathematics 60, n^o 5 (octobre 2008) : 961–74. http://dx.doi.org/10.4153/cjm-2008-042-7.

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AbstractWe study the regularity of the higher secant varieties of ℙ1 × ℙn, embedded with divisors of type (d, 2) and (d, 3). We produce, for the highest defective cases, a “determinantal” equation of the secant variety. As a corollary, we prove that the Veronese triple embedding of ℙn is not Grassmann defective.

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Bernardi, Alessandra, Enrico Carlini, Maria Catalisano, Alessandro Gimigliano et Alessandro Oneto. « The Hitchhiker Guide to : Secant Varieties and Tensor Decomposition ». Mathematics 6, n^o 12 (8 décembre 2018) : 314. http://dx.doi.org/10.3390/math6120314.

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We consider here the problem, which is quite classical in Algebraic geometry, of studying the secant varieties of a projective variety X. The case we concentrate on is when X is a Veronese variety, a Grassmannian or a Segre variety. Not only these varieties are among the ones that have been most classically studied, but a strong motivation in taking them into consideration is the fact that they parameterize, respectively, symmetric, skew-symmetric and general tensors, which are decomposable, and their secant varieties give a stratification of tensors via tensor rank. We collect here most of the known results and the open problems on this fascinating subject.

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Heydari, Hoshang. « Geometrical Structure of Entangled States and the Secant Variety ». Quantum Information Processing 7, n^o 1 (13 janvier 2008) : 43–50. http://dx.doi.org/10.1007/s11128-007-0071-4.

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Guan, Yonghui. « Equations for secant varieties of Chow varieties ». International Journal of Algebra and Computation 27, n^o 08 (décembre 2017) : 1087–111. http://dx.doi.org/10.1142/s0218196717500515.

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The Chow variety of polynomials that decompose as a product of linear forms has been studied for more than 100 years. Finding equations in the ideal of secant varieties of Chow varieties would enable one to prove Valiant's conjecture [Formula: see text]. In this paper, I use the method of prolongation to obtain equations for secant varieties of Chow varieties as [Formula: see text]-modules.

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Cattaneo, Andrea. « The degree of the tangent and secant variety to a projective surface ». Advances in Geometry 20, n^o 2 (28 avril 2020) : 233–48. http://dx.doi.org/10.1515/advgeom-2019-0015.

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AbstractWe present a way of computing the degree of the secant (resp. tangent) variety of a smooth projective surface, under the assumption that the divisor giving the embedding in the projective space is 3-very ample. This method exploits the link between these varieties and the Hilbert scheme 0-dimensional subschemes of length 2 of the surface.

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CHIANTINI, LUCA, et CIRO CILIBERTO. « ON THE CONCEPT OF k-SECANT ORDER OF A VARIETY ». Journal of the London Mathematical Society 73, n^o 02 (avril 2006) : 436–54. http://dx.doi.org/10.1112/s0024610706022630.

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Achilles, Rüdiger, Mirella Manaresi et Peter Schenzel. « A Degree Formula for Secant Varieties of Curves ». Proceedings of the Edinburgh Mathematical Society 57, n^o 2 (21 août 2013) : 305–22. http://dx.doi.org/10.1017/s0013091513000497.

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AbstractUsing the Stückrad–Vogel self-intersection cycle of an irreducible and reduced curve in pro-jective space, we obtain a formula that relates the degree of the secant variety, the degree and the genus of the curve and the self-intersection numbers, the multiplicities and the number of branches of the curve at its singular points. From this formula we deduce an expression for the difference between the genera of the curve. This result shows that the self-intersection multiplicity of a curve in projectiveN-space at a singular point is a natural generalization of the intersection multiplicity of a plane curve with its generic polar curve. In this approach, the degree of the secant variety (up to a factor 2), the self-intersection numbers and the multiplicities of the singular points are leading coefficients of a bivariate Hilbert polynomial, which can be computed by computer algebra systems.

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Vermeire, Peter. « Regularity and normality of the secant variety to a projective curve ». Journal of Algebra 319, n^o 3 (février 2008) : 1264–70. http://dx.doi.org/10.1016/j.jalgebra.2007.10.032.

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Catalisano, Maria Virginia, Anthony V. Geramita, Alessandro Gimigliano et Yong-Su Shin. « The secant line variety to the varieties of reducible plane curves ». Annali di Matematica Pura ed Applicata (1923 -) 195, n^o 2 (24 décembre 2014) : 423–43. http://dx.doi.org/10.1007/s10231-014-0470-y.

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Ballico, E., et C. Fontanari. « On the secant varieties to the osculating variety of a Veronese surface ». Central European Journal of Mathematics 1, n^o 3 (septembre 2003) : 315–26. http://dx.doi.org/10.2478/bf02475212.

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Laface, Antonio, et Luca Ugaglia. « On multiples of divisors associated to Veronese embeddings with defective secant variety ». Bulletin of the Belgian Mathematical Society - Simon Stevin 16, n^o 5 (décembre 2009) : 933–42. http://dx.doi.org/10.36045/bbms/1260369407.

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Vermeire, Peter. « Equations and syzygies of the first secant variety to a smooth curve ». Proceedings of the American Mathematical Society 140, n^o 8 (1 août 2012) : 2639–46. http://dx.doi.org/10.1090/s0002-9939-2011-11392-3.

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Ballico, Edoardo, et Alessandra Bernardi. « On the ranks of the third secant variety of Segre–Veronese embeddings ». Linear and Multilinear Algebra 67, n^o 3 (25 janvier 2018) : 583–97. http://dx.doi.org/10.1080/03081087.2018.1430117.

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Oeding, Luke, et Steven V. Sam. « Equations for the Fifth Secant Variety of Segre Products of Projective Spaces ». Experimental Mathematics 25, n^o 1 (12 octobre 2015) : 94–99. http://dx.doi.org/10.1080/10586458.2015.1037872.

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Ballico, E. « On the secant varieties to the tangent developable of a Veronese variety ». Journal of Algebra 288, n^o 2 (juin 2005) : 279–86. http://dx.doi.org/10.1016/j.jalgebra.2005.03.031.

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Van Maldeghem, Hendrik, et Magali Victoor. « On Severi varieties as intersections of a minimum number of quadrics ». Cubo (Temuco) 24, n^o 2 (août 2022) : 307–31. http://dx.doi.org/10.56754/0719-0646.2402.0307.

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Let \({\mathscr{V}}\) be a variety related to the second row of the Freudenthal-Tits Magic square in \(N\)-dimensional projective space over an arbitrary field. We show that there exist \(M\leq N\) quadrics intersecting precisely in \({\mathscr{V}}\) if and only if there exists a subspace of projective dimension \(N-M\) in the secant variety disjoint from the Severi variety. We present some examples of such subspaces of relatively large dimension. In particular, over the real numbers we show that the Cartan variety (related to the exceptional group \({E_6}\)\((\mathbb R)\)) is the set-theoretic intersection of 15 quadrics.

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Ballico, E. « Symmetric Tensor Rank and Scheme Rank : An Upper Bound in terms of Secant Varieties ». Geometry 2013 (8 septembre 2013) : 1–3. http://dx.doi.org/10.1155/2013/614195.

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Let X⊂ℙr be an integral and nondegenerate variety. Let c be the minimal integer such that ℙr is the c-secant variety of X, that is, the minimal integer c such that for a general O∈ℙr there is S⊂X with #(S)=c and O∈〈S〉, where 〈 〉 is the linear span. Here we prove that for every P∈ℙr there is a zero-dimensional scheme Z⊂X such that P∈〈Z〉 and deg(Z)≤2c; we may take Z as union of points and tangent vectors of Xreg.

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Ottaviani, Giorgio. « An Invariant Regarding Waring’s Problem for Cubic Polynomials ». Nagoya Mathematical Journal 193 (2009) : 95–110. http://dx.doi.org/10.1017/s0027763000026040.

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AbstractWe compute the equation of the 7-secant variety to the Veronese variety (P4,O(3)), its degree is 15. This is the last missing invariant in the Alexander-Hirschowitz classification. It gives the condition to express a homogeneous cubic polynomial in 5 variables as the sum of 7 cubes (Waring problem). The interesting side in the construction is that it comes from the determinant of a matrix of order 45 with linear entries, which is a cube. The same technique allows to express the classical Aronhold invariant of plane cubics as a pfaffian.

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SHIN, YONG SU. « SECANTS TO THE VARIETY OF COMPLETELY REDUCIBLE FORMS AND THE HILBERT FUNCTION OF THE UNION OF STAR-CONFIGURATIONS ». Journal of Algebra and Its Applications 11, n^o 06 (14 novembre 2012) : 1250109. http://dx.doi.org/10.1142/s0219498812501095.

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We prove that if 𝕏 ≔ 𝕏(t, s) is the union of two linear star-configurations of type t × s for 3 ≤ t ≤ 9 and s ≥ t in ℙ2, then 𝕏 has generic Hilbert function. We also show that (I𝕏)s = {0} when 𝕏 is the union of two linear star-configurations of type s × s for s ≥ 6. Moreover, using the two results with the work in [E. Arrondo and A. Bernardi, On the variety parameterizing completely decomposable polynomials, J. Pure Appl. Algebra215(3) (2011) 201–220], we prove that the secant variety Sec 1( Split s(ℙn)) is not defective for s ≥ 3 and n ≥ 2.

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Beheshti, Roya, et David Eisenbud. « Fibers of generic projections ». Compositio Mathematica 146, n^o 2 (2 février 2010) : 435–56. http://dx.doi.org/10.1112/s0010437x09004503.

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AbstractLet X be a smooth projective variety of dimension n in Pr, and let π:X→Pn+c be a general linear projection, with c>0. In this paper we bound the scheme-theoretic complexity of the fibers of π. In his famous work on stable mappings, Mather extended the classical results by showing that the number of distinct points in the fiber is bounded by B:=n/c+1, and that, when n is not too large, the degree of the fiber (taking the scheme structure into account) is also bounded by B. A result of Lazarsfeld shows that this fails dramatically for n≫0. We describe a new invariant of the scheme-theoretic fiber that agrees with the degree in many cases and is always bounded by B. We deduce, for example, that if we write a fiber as the disjoint union of schemes Y′ and Y′′ such that Y′ is the union of the locally complete intersection components of Y, then deg Y′+deg Y′′red≤B. Our method also gives a sharp bound on the subvariety of Pr swept out by the l-secant lines of X for any positive integer l, and we discuss a corresponding bound for highly secant linear spaces of higher dimension. These results extend Ran’s ‘dimension +2 secant lemma’.

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Draisma, Jan, et Rob H. Eggermont. « Plücker varieties and higher secants of Sato’s Grassmannian ». Journal für die reine und angewandte Mathematik (Crelles Journal) 2018, n^o 737 (1 avril 2018) : 189–215. http://dx.doi.org/10.1515/crelle-2015-0035.

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AbstractEvery Grassmannian, in its Plücker embedding, is defined by quadratic polynomials. We prove a vast, qualitative, generalisation of this fact to what we callPlücker varieties. A Plücker variety is in fact a family of varieties in exterior powers of vector spaces that, like the Grassmannian, is functorial in the vector space and behaves well under duals. A special case of our result says that for each fixed natural numberk, thek-th secant variety ofanyPlücker-embedded Grassmannian is defined in bounded degree independent of the Grassmannian. Our approach is to take the limit of a Plücker variety in the dual of a highly symmetric space known as theinfinite wedge, and to prove that up to symmetry the limit is defined by finitely many polynomial equations. For this we prove the auxiliary result that for every natural numberpthe space ofp-tuples of infinite-by-infinite matrices is Noetherian modulo row and column operations. Our results have algorithmic counterparts: every bounded Plücker variety has a polynomial-time membership test, and the same holds for Zariski-closed, basis-independent properties ofp-tuples of matrices.

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Issa, Usama, Fam Saeed, Yehia Miky, Muwaffaq Alqurashi et Emad Osman. « Hybrid AHP-Fuzzy TOPSIS Approach for Selecting Deep Excavation Support System ». Buildings 12, n^o 3 (3 mars 2022) : 295. http://dx.doi.org/10.3390/buildings12030295.

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This paper introduces and further applies an approach to support the decision makers in construction projects differentiating among a variety of deep excavation supporting systems (DESSs). These kinds of problems include dealing with uncertainty in data, multi-criteria affecting the decision, and multi-alternatives to select one from them. The proposed approach combines the analytic hierarchy process (AHP) with the fuzzy technique for order of preference by similarity to ideal solution (fuzzy TOPSIS) in a multicriteria decision-making (MCDM) model. The MCDM model emphasize the ability to combine expert knowledge, cost calculations, and laboratory test results for soil properties to achieve the scope. The model proved it had a superior ability to deal with the complexity and vague data that are related to construction projects. Furthermore, it was applied to a real case study for a governmental housing project in Egypt. Secant pile walls, sheet pile walls, and soldier piles and lagging are selected and studied as being the most common DESSs and as they satisfy the project requirements. The model utilized four criteria and fourteen comparing factors, including site characteristics, safety, cost, and environmental impacts. Based on the results of the model application on the investigated case study, a decision was reached that using secant piles as a supporting system in this project is mostly preferred. Furthermore, sheet pile wall, and soldier piles and lagging, come next in the ranking order. A sensitivity analysis is carried out to investigate how sensitive the results are to the criteria weights. In addition, the paper discusses in detail the reasons and factors which affect and control the decision-making process.

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Moughrabi, Issam A. R., et Saeed Askary. « New Dual Parameter Quasi-Newton Methods for Unconstrained Nonlinear Programs ». International Journal of Strategic Decision Sciences 10, n^o 3 (juillet 2019) : 74–94. http://dx.doi.org/10.4018/ijsds.2019070105.

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A framework model of multi-step quasi-Newton methods developed which utilizes values of the objective function. The model is constructed using iteration genereted data from the m+1 most recent iterates/gradient evaluations. It hosts double free parameters which introduce a certain degree of flexibility. This permits the interpolating polynomials to exploit available computed function values which are otherwise discarded and left unused. Two new algorithms are derived for those function values incorporated in the update of the inverse Hessian approximation at each iteration to accelerate convergence. The idea of incorporating function values configure quasi-Newton methods, but the presentation constitutes a new approach for such algorithms. Several earlier works only include function values data in the update of the Hessian approximation numerically to improve the convergence of Secant-like methods. The methods are a useful tool for solving nonlinear problems arising in engineering, physics, machine learning, decision science, approximations techniques to Bayesian Regressors and a variety of numerical analysis applications.

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Emery, Keith. « Photovoltaic Efficiency Measurements ». MRS Bulletin 19, n^o 6 (juin 1994) : 64–66. http://dx.doi.org/10.1557/s0883769400036800.

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A variety of performance indicators have been employed by the photovoltaic (PV) community to rate the performance of PV cells, modules, and arrays. The PV power conversion efficiency under a set of standard reporting conditions serves as a basis for meaningful comparisons of PV performance, within and among PV technologies. PV efficiency is defined as 100 times the maximum PV electrical power density produced divided by the incident light power at a reference PV temperature, total irradiance, and spectral irradiance. Standard reporting conditions commonly used by the PV community are summarized in Table I.The direct and global reference spectra were generated by a comprehensive Monte-Carlo computer model and actually integrate to 768 W m−2 and 964 W m−2. The terrestrial PV community has arbitrarily assigned a 1-sun total irradiance of 1,000 W m−2 for the global and direct reference spectra. The term “direct” in Table I refers to the direct-normal (5° field of view about the sun) component of the global spectral irradiance distribution. The term “global” in Table I refers to the spectral irradiance distribution on a 37-tilted south-facing surface with a solar zenith angle of 48.2° (AM1.5). The terms AM1 or AM1.5 are often used to refer to standard spectra, but the relative optical air mass (AM) is a geometrical quantity and can be obtained by taking the secant of the angle between the sun and the zenith.

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Svistunov, V. V. « Breccias of Svoboda ore area of Malmyzhskoe gold-copper porphyry deposit (Khabarovsk territory) ». Proceedings of higher educational establishments. Geology and Exploration, n^o 5 (28 novembre 2019) : 50–57. http://dx.doi.org/10.32454/0016-7762-2019-5-50-57.

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The texture and variety of types of breccia bodies of the ore section of the Svoboda at the Malmyzhskoye deposit have been studied and described: a large one — the complex structure of eruptive (hydrothermal-magmatic) breccias and a relatively small — the columnar body of phreatic breccias. Eruptive breccias are intra-ore with respect to gold-copper mineralization. The detrital part in them is represented mainly by metasomatically altered intrusive rocks of the 1st phase of introduction and sedimentary formations of the cretaceous Largasinsky suite. Breccia cementing material is potassium feldspar-quartz-chlorite-sericite mass, which is an intensively metasomatically altered rock of the 2nd intrusive phase of intrusion. Ore mineralization in breccias has a veindisseminated texture and is part of the clastic part of breccias and is also superimposed on the already formed breccia bodies in the process of their metasomatic alternation. Phreatic breccias formed at the final stages of the development of the porphyry system. They are distinguished by low copper and gold contents and sharp secant contacts with the rocks surrounding them. The composition of the debris is generally similar to eruptive breccia, cement is quartz-sericite-epidote-chlorite. The position of ore mineralization is similar to that in eruptive breccias, but it is manifested to a much lesser extent. According to the proposed genetic model, the formation of the body of eruptive breccias occurred as a result of fluidization of rocks located in the arches of the intrusive body, followed by the introduction of significant volumes of magmatic melt. Subsequently, when rising, the fluids interacted with the cold near-surface waters, which caused the formation of phreatic breccias. The studied features of breccia formations are in a good agreement with the classical model of copper-porphyry deposits of the world.

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Auffarth, Robert, Giulio Codogni et Riccardo Salvati Manni. « The Gauss map and secants of the Kummer variety ». Bulletin of the London Mathematical Society 51, n^o 3 (19 mars 2019) : 489–500. http://dx.doi.org/10.1112/blms.12244.

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Kusuma, Irawan W. « Secang (Caesalpinia Sappan) : Telaah Aktifitas Biologis Dan Potensi Pemanfaatannya ». Jurnal Riset Teknologi Industri 1, n^o 2 (7 juillet 2016) : 14–23. http://dx.doi.org/10.26578/jrti.v1i2.1397.

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Plant resources serve abundant useful biological active substances. Secang, a local name of Caesalpinia sappan (Leguminosae), promise high possibility for a broad-ranging purposes due to its biological activities. In traditional manner, the wood of secang is used for coloring agent for beverages, foods and cosmetics. Several phytochemicals were isolated from the secang extract, including brazilin, brezilein, protosappanin, 4-0-methy/ sappanol, caesalpin, kampesterol and b-sitosterol. Secang extract and the compounds thereformhave been reported to possess a huge variety of biological activities such asantioxidant, antibacterial, antifungal, anticancer, natural contraceptive and xanthine oxidase (XO) inhibitor.The biological activities of the extracts andph vtochemicals ftrom secang may give scientific basis for their application in agricultural, food processing, medical and other industries.

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Devroye, Luc. « On random variate generation for the generalized hyperbolic secant distributions ». Statistics and Computing 3, n^o 3 (septembre 1993) : 125–34. http://dx.doi.org/10.1007/bf00147775.

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Ida Rosanti, Ali Sadikin et Retno Prasetia. « ANALISIS VARIASI TEMPERATUR PRA MORDAN PEWARNA KAYU SECANG DAN DAUN JATI SERTA PENERAPAN HEDONIC TEST PADA KUALITAS SERAT KENAF INDUSTRI FASHION ». JURNAL AGRIMENT 5, n^o 02 (1 décembre 2020) : 132–41. http://dx.doi.org/10.51967/jurnalagriment.v5i02.302.

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This study aims to determine the effect of pre-mordant material on kenaf fiber coloring using secang wood and teak leaves, to determine the Henodic Test method in classifying its quality, as well as to determine the significant effect on the color of kenaf fiber, and to determine the level of consumer preference for kenaf fiber. natural dyes. The research method used was an experiment with a variety of pre-mordant materials (alum, lime, vinegar). From the test, it was found that the color direction of the kenaf fiber was reddish purple to light brown, so the average value of fastness to washing was 4 (good). From this activity, it was concluded that the addition of secang wood and teak leaves as pre- mordant materials coupled with the effect of pH on the staining of kenaf fibers with secang wood extract provided variations in the direction of color and the value of color fastness to washing. Kenaf fiber is an environmentally friendly alternative to textile raw materials. This study used the Hedonic Test method with the Kruskal Wallis test. The results of this study were that there was no significant effect on the combination of compost application and pesticide application with natural dyes of secang wood and teak leaves on the color of kenaf fibers and there was no effect on the level of consumer preference for kenaf fiber with natural dyes.

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Vershinin, Alexander V., Evgeny A. Elisafenko et Elena V. Evtushenko. « Genetic Redundancy in Rye Shows in a Variety of Ways ». Plants 12, n^o 2 (7 janvier 2023) : 282. http://dx.doi.org/10.3390/plants12020282.

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Fifty years ago Susumu Ohno formulated the famous C-value paradox, which states that there is no correlation between the physical sizes of the genome, i.e., the amount of DNA, and the complexity of the organism, and highlighted the problem of genome redundancy. DNA that does not have a positive effect on the fitness of organisms has been characterized as “junk or selfish DNA”. The controversial concept of junk DNA remains viable. Rye is a convenient subject for yet another test of the correctness and scientific significance of this concept. The genome of cultivated rye, Secale cereale L., is considered one of the largest among species of the tribe Triticeae and thus it tops the average angiosperm genome and the genomes of its closest evolutionary neighbors, such as species of barley, Hordeum (by approximately 30–35%), and diploid wheat species, Triticum (approximately 25%). The review provides an analysis of the structural organization of various regions of rye chromosomes with a description of the molecular mechanisms contributing to their size increase during evolution and the classes of DNA sequences involved in these processes. The history of the development of the concept of eukaryotic genome redundancy is traced and the current state of this problem is discussed.

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Tartynska, Ganna, Іryna Zhuravel, Viktoriia Kyslychenko et Viktoriia Hutsol. « Comparative analysis of the fatty acid composition of raw material of rye (Khamarka variety) and barley (Shedevr variety) of Ukrainian selection ». ScienceRise : Pharmaceutical Science, n^o 5(33) (29 octobre 2021) : 57–63. http://dx.doi.org/10.15587/2519-4852.2021.243361.

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Introduction. Sowing rye (Secale cereale L.) and common barley (Hordéum vulgáre L.) are annual herbaceous plants of the Poaceae family, they are widely cultivated in many countries around the world as cereals and fodder crops. Sufficient raw material base of sowing rye and barley makes them promising sources for new drugs. Materials and methods. The fatty acid composition in lipophilic fractions of seeds, stems and leaves of sowing (Khamarka variety) and common barley (Shedevr variety) was studied by gas chromatography. Results. As a result of the study, the quantitative content of 14 fatty acids in the stems and leaves of barley, 13 – in the leaves of rye and 12 – in the stems of rye and in both types of studied seeds was identified and established. In all types of the studied raw materials, unsaturated fatty acids were quantitatively predominant, the content of which prevailed in seeds of rye – 82.89 % and barley – 76.35 %. In stems of common barley their content was 64.04 %, leaves of common barley – 66.31 % of the amount. In stems and leaves of rye, the predominance of unsaturated fatty acids over saturated ones was insignificant: 49.00 % vs. 47.05 % and 53.70 % vs. 43.03 %, respectively. Among the unsaturated fatty acids, linoleic and linolenic acids dominated. Palmitic acid predominated among the saturated raw materials in all types of studied raw materials Conclusions. Quantitative content of fatty acids in seeds, stems and leaves of sowing rye (Khamarka variety) and common barley (Shedevr variety) was identified and established by gas chromatography. The results of the research indicate a rich fatty acid composition of the studied raw materials and can be used to create drugs based on them

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Saputra, H., et Z. Mutaqin. « Morphological Responses of Edamame Soybean and Sweet Corn Planted in Intercropping with Combinations of Plant Populations on Three Varieties of Sweet Corn ». IOP Conference Series : Earth and Environmental Science 1012, n^o 1 (1 avril 2022) : 012072. http://dx.doi.org/10.1088/1755-1315/1012/1/012072.

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Abstract The intercropping pattern is a plant cultivation system that is very suitable for increasing productivity on marginal dry land with relatively low fertility levels. The regulation of plant population density and the selection of appropriate varieties can minimize the negative influence of competition between sweet corn and edamame soybeans to optimize the growth of both plants. The purpose of this study was to (1) determine the best plant population density in the intercropping pattern of sweet corn and edamame soybean (2) determine the best varieties in the intercropping pattern of sweet corn and edamame soybean and (3) determine the combination of plant population density and the best crop varieties in the intercropping pattern. The treatments were arranged in a factorial consisting of 2 factors. The first factor was the population density of edamame soybeans which consisted of three levels: 1 row of edamame soybeans between rows of sweet corn (B1), 2 rows of edamame soybeans between rows of sweet corn (B2), and 3 rows of edamame soybeans between rows of sweet corn (B3). The second factor is three sweet corn varieties, namely the Secada variety (V1), the Exotic variety (V2), and the Golden Sweet variety so that there are nine treatment combinations. The results showed that (1) the plant population density model of 2 rows of edamame between rows of sweet corn and sweet corn varieties Secada can produce the best sweet corn growth by increasing the wet weight of sweet corn, (2) sweet corn varieties that have the most suitable for intercropping in this research model is the Secada variety, based on plant height, the number of leaves, stem diameter, and plant wet weight, (3) edamame soybean produces relatively the same morphological growth in all population density models and sweet corn varieties used.

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Haryanti, Sari, Yuli Widiyastuti et Nuning Rahmawati. « Cytotoxic and MMPs inhibitory activities of Sappan Wood (Caesalpiniasappan L.) : various extracts on 4T1 breast cancer cell line ». Health Science Journal of Indonesia 9, n^o 1 (11 octobre 2018) : 51–56. http://dx.doi.org/10.22435/hsji.v9i1.483.

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Latar belakang: Kayu secang (Caesalpinia sappan L.) merupakan salah satu tanaman potensial dengan berbagai khasiat obat, termasuk antikanker. Gelatinase (MMP-2 dan MMP-9) merupakan matriks metaloproteinase (MMPs) dan memiliki peran penting dalam inisiasi, invasi, dan metastasis kanker. Penelitian ini bertujuan untuk menguji aktivitas sitotoksik dan penghambatan MMP dari ekstrak kayu secang pada sel kanker payudara 4T1. Metode: Serbuk kayu secang dibagi menjadi 4 bagian, masing-masing diekstraksi dengan pelarut berbeda. Etanol 96%, etanol 70%, dan metanol digunakan untuk metode maserasi, sedangkan air untuk metode infusa. Uji MTT digunakan untuk menentukan efek sitotoksisitas, dan uji gelatin zymography untuk mendeteksi aktivitas MMP-2 dan MMP-9. Profil fitokimia ekstrak diamati dengan Kromatografi Lapis Tipis (KLT). Hasil: Profil fitokimia ekstrak air menunjukkan profil KLT yang berbeda, sementara tiga ekstrak lainnya memiliki profil yang sama. Ekstrak etanol 96% kayu secang memberikan efek sitotoksik paling kuat terhadap 4T1 dengan nilai IC50 13,1 μg/mL, diikuti metanol (21,4 μg/mL), etanol 70% (22,5 μg/mL) dan air (25,5 μg/mL). Analisis gelatin zymograph dengan software ImageJ menunjukkan bahwa semua ekstrak kecuali air, menghambat aktivitas gelatinolitik MMP-9 Kesimpulan: Ekstrak kayu secang dengan berbagai pelarut polar memiliki aktivitas sitotoksik dan penghambatan MMP pada sel kanker payudara 4T1 dan berpotensi untuk dikembangkan sebagai anti kanker payudara. Kata kunci: Caesalpinia sappan, MMP, sitotoksik, 4T1 Abstract Background: Sappan wood (Caesalpinia sappan L.) is one of potential plant with wide variety of medicinal properties, including anticancer. Gelatinases (MMP-2 and MMP-9) are the member of matrix metalloproteinases (MMPs) and having a key role in cancer initiation, invasion, and metastasis. This study evaluated the cytotoxic and MMPs inhibitory activities of sappan wood in various extract on 4T1 breast cancer cell lines. Methods: Sappan wood powder were divided into 4 parts, each part was extracted with different solvent. Ethanol 96%, ethanol 70%, and methanol were used for maceration methods, while water for infusion method. MTT assay used to identify cytotoxicity effect, and gelatin zymography assay to detect the activity of MMP-2 and MMP-9. Phytochemical profiling of the extract were observed by Thin Layer Chromatography (TLC). Results: Phytocemical profiling of water extract showed different TLC profile, while three others had similar profile. The results of MTT assay showed that ethanolic 96% extract exhibited the strongest cytotoxic effect against 4T1 with the IC50 value 13,1 μg/mL, followed by methanolic (21,4 μg/mL), ethanolic 70% (22,5 μg/mL) and water (25,5 μg/mL). The analysis of gelatin zymograph bands using ImageJ software proved that all extracts except water, inhibited gelatinolytic activity of MMP-9. Conclusion: The results of the study suggest that various extract of the sappan wood have been found to posses cytotoxic and MMPs inhibitory activities. Keywords: Caesalpinia sappan, MMP’s, cytotoxic, 4T1

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South, Michelle, Leanne L. Dillard et Deidre D. Harmon. « 57 Cool-season Annual Forage Variety Selection Tool for the Southeastern United States ». Journal of Animal Science 100, Supplement_1 (8 mars 2022) : 2–3. http://dx.doi.org/10.1093/jas/skac028.003.

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Abstract Cool-season annual forage varieties of annual ryegrass (Lolium multiflorum), cereal rye (Secale cereale), wheat (Triticum aestivum), and triticale (Triticale hexaploide Lart.) are often chosen on the basis of availability and affordability rather than performance. The objective of this study was to create a source of collaborative data that would aid producers in selection of superior varieties of cool-season annual forages that perform well across varying years, geographic regions, and environments. Forage yield data was collected from forage variety trials conducted in the years of 2015–2020 by University of Georgia, University of Tennessee, Pennsylvania State University, University of Kentucky, and Mississippi State University. Testing occurred at 18 different sites and across 7 states in the Eastern United States. Data from 166 annual ryegrass, 35 cereal rye, 93 wheat, and 48 triticale individual varieties were collected and standardized by expressing yields as a percentage of the mean within a given testing site-year. Standardized means were averaged across all available site-years for each variety within a species and a coefficient of variation (CV) was calculated. Varieties in each species were categorized by their relative mean yield and CV and varieties that had above average relative mean and low CV were considered desirable. The desired annual ryegrass varieties included: Marshall, K014-WLS, K0140-WEMA, FL Red 4X LATE, Angusta, RM exp-2013A, and FL AT-3. The limitedly tested but qualifying varieties of cereal rye were Wintergrazer 70, Wrens Abruzzi, NF99362, Bates RS4, and Goku, wheat were FLLA10033C-6, GA-09129-16E55, GA-051207-14E53, GA-04417-12E33, GA-03564-12E6, GA-071518-16E39, W010025-H2, PGX-16-4, AGS 3040, Oglethorpe, AGS 3030, PGX 16-1, SS EXP 8629, W010025R1, GA-09377-16LE18, GoWheat 2032, SRW 9410, and GA-071630-12LE9, and triticale were Wintermax, and TriCal 815. Results from this study will aid producers in the identification of desired cool-season annual forage varieties that consistently perform well in varying environmental conditions.

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El Broudi, S., N. Zehhar, N. Abdenouri, A. Boussaid, A. Hafidi et F. Benkhalti. « Investigation of drying kinetics and drying conditions on biochemical, sensory, and microstructural parameters of “Sefri” pomegranate arils (Punica granatum L. a Moroccan variety) ». Revista Mexicana de Ingeniería Química 21, n^o 3 (18 août 2022) : 1–25. http://dx.doi.org/10.24275/rmiq/alim2813.

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Kantar, Michael, et Paul Porter. « Relationship between Planting Date, Growing Degree Days and the Winter Rye (Secale cereale L.) Variety “Rymin” in Minnesota ». Crop Management 13, n^o 1 (2014) : CM—2013–0096—RS. http://dx.doi.org/10.2134/cm-2013-0096-rs.

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Ku, Ja-Hwan, Ouk-kyu Han, Young-Jin Oh, Tae-Il Park, Dae-Wook Kim, Byung-Joo Kim, Myoung Ryoul Park et Kyung-Yoon Ra. « An Early-Maturing and High-Biomass Tetraploid Rye (Secale cereale L.) Variety ‘Daegokgreen’ for Forage Use ». Journal of The Korean Society of Grassland and Forage Science 40, n^o 4 (30 décembre 2020) : 209–15. http://dx.doi.org/10.5333/kgfs.2020.40.4.209.

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Prihanani, Prihanani, Danner Sagala et Yondi Yonadi. « STUDI PEMBUATAN MINYAK KELAPA MURNI SECARA ENZIMATIS DENGAN MENGGUNAKAN BERBAGAI TINGKAT KONSENTRASI ENZIM NANAS PADA DUA JENIS KELAPA ». Jurnal Agroqua : Media Informasi Agronomi dan Budidaya Perairan 11, n^o 1 (8 mai 2017) : 24. http://dx.doi.org/10.32663/ja.v11i1.42.

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Virgin coconut oil can be proccessed in many ways to meet market quality. One of them is enzymaticly process. The aim of this research was to know bromelin enzyme concentration on two varieties of coconut. The experiment was conducted at PT. Sandabi Indah Lestari laboratory, Lunjuk Village, Seluma Barat Subistrict and Seluma Regency from in July 2012. The experiment was arranged in completely randomized design with two factos and three replication. The first faktor was variety of coconut consisted of Kelapa dalam and Kelapa hibrida. The second factor was bromelin enzyme concentration consisted of LIPI enzyme (as control), 50, 100, 150 gram. Variety affected most significantly on virgin coconut oil rendement. Kelapa dalam variety produced the higher virgin coconut oil than kelapa hibrida variety. However, variety and enzyme were affected unsignificant on water content of the virgin coconut oil.

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Vegas, Rodolfo, Amparo Zavaleta et Carlos Vegas. « Effect of temperature on drying kinetics and color of seed Lupinus mutabilis defatted paste, criolla variety ». SCIÉNDO 20, n^o 1 (31 mars 2017) : 39–45. http://dx.doi.org/10.17268/sciendo.2017.005.

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Birbik, Muhammad Hafil. « TAKHRIJ HADITS (METODE PENELITIAN SUMBER-SUMBER HADITS UNTUK MEMINIMALISIR PENGUTIPAN HADITS SECARA SEPIHAK) ». Ar-Risalah : Media Keislaman, Pendidikan dan Hukum Islam 18, n^o 1 (7 mai 2020) : 174. http://dx.doi.org/10.29062/arrisalah.v18i1.281.

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This article is aimed to describe about “takhrij Hadits”, that includes the meaning, advantage and methods. From relevant refrences known that “takhrij Hadits” is and effort to find ”matan” and “sanad” of Hadits, compeletely from the original references. It clear that the cuality of Hadits is even known by collector directly through researches. The advantages of takhrij are: (a) collecting variety of sanad of the Hadits (b) collecting variety of matan of the Hadits. They’re the important materials for the research. To implement takhrij Hadits can be used several methods. (1) takhrij from spelling in matan of Hadits, (2) takhrij from first spelling of the Hadits, (3) takhrij from first collector, (4) takhrij from the topic of Hadits, (5) takhrij from classification of Hadits.

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MATEI, GHEORGHE, MIRELA PARASCHIVU et RETA DRĂGHICI. « TECHNOLOGICAL ASPECTS OF RYE CULTIVATED IN THE CONDITIONS OF SANDY SOILS IN SOUTHERN OLTENIA ». "Annals of the University of Craiova - Agriculture, Montanology,Cadastre Series " 51, n^o 1 (18 décembre 2020) : 126–33. http://dx.doi.org/10.52846/aamc.2021.01.17.

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Rye (Secale cereale L.) is an important crop in Europe, where it occupies about 90% of the world's area cultivated with this cereal (FAOSTAT, 2018), mainly in the countries of Central and Eastern Europe. The main research highlights the mechanisms of adaptation of rye culture to climate change, aimed at identifying genotypes that have a good behavior in culture under conditions of abiotic (thermohydric) and biotic stress (pathogens and pests) in order of restoring the production capacity and protection of agroecosystems in the area of sandy soils by promoting in culture some genotypes tolerant to thermohydric stress. In the two experimented years of 2020 and 2021 the obtained results prove the new genotypes promoted on the market had a higher capacity of production than the Control (Suceveana variety), with an average yield of over 4555 kg/ha registered at Serafino genotype in the conditions of a sandy soil with a low natural fertility, poorly supplied with total nitrogen (0.05- 0.07%). In average, during the tested years, the attack frequencies of pests manifested in the comparative rye culture, as well as the attack intensities did not show significant differences from one variety to another, significant differences compared to the control variety (Suceveana) being observed only in the case of Serafino variety.

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Wijayanti, Endang, et Anas D. Susila. « Pertumbuhan dan Produksi Dua Varietas Tomat (Lycopersicon esculentumMill.) secara Hidroponik dengan beberapa Komposisi Media Tanam ». Buletin Agrohorti 1, n^o 1 (11 janvier 2013) : 104. http://dx.doi.org/10.29244/agrob.1.1.104-112.

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<p style="text-align: justify;">The objectives of this researchwasto determine the effect of growing media composition on growth and production of two varieties of tomatoes in a hydroponic system. The research used Randomized Complate Block Design (RCBD) with two factors, they were tomato varieties and growing media composition. The tomato varieties were (Arthaloka, Permata) and growing media compotition were 100% husk (v/v), 75% husk + 25% bamboo leaves compost (v/v), 50% husks + 50% bamboo leaves compost (v/v), 25% husk + 75% bamboo leaves compost (v/v), and 100% bamboo leaves compost (v/v). Permata variety better than Arthaloka variety, based the higher number of flower and flower bunches, number of fruit, weight of fruit and grade of fruit. Bamboo leaves compost increased heigh of plant at 2-5 week after transplanting (WAT), number of leaves at 2-4 WAT, number of flower at 4-5 WAT, and 7-8 WAT, and number of flowers bunches at 5–11 WAT. The used of bamboo leaf compost 50% (v/v) and 75% (v/v) increased fruit number of tomato Permata variety at 7 WAT.</p><p>Keywords: rice husk, bamboo leaf compost, hydroponics, tomato production</p>

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Skrypnik, Liubov, Pavel Maslennikov, Anastasia Novikova et Mikhail Kozhikin. « Effect of Crude Oil on Growth, Oxidative Stress and Response of Antioxidative System of Two Rye (Secale cereale L.) Varieties ». Plants 10, n^o 1 (14 janvier 2021) : 157. http://dx.doi.org/10.3390/plants10010157.

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Rye (Secale cereale L.) is one of the most important cereal crops in Eastern and Northern Europe, showing better tolerance to environmental stress factors compared to wheat and triticale. Plant response to the crude oil-polluted soil depends on plant species, oil concentration, time of exposure, etc. The current study is aimed at investigating the growth, oxidative stress and the response of antioxidative system of two rye varieties (Krona and Valdai) cultivated on crude oil-contaminated soils at different concentrations (1.5, 3.0, 6.0, and 12.0%). Inhibition of rye growth was observed at crude oil concentrations of above 3% for above-ground plant parts and of above 1.5% for roots. A decrease in content of chlorophyll a and total chlorophylls in Krona variety was detected at 1.5% oil concentration in soil and in Valdai variety at 3% oil concentration. Compared with the control, the content of malondialdehyde was significantly increased in the Krona variety at 3% oil concentration and in Valdai variety at 6% oil concentration. The crude oil-induced oxidative stress was minimized in rye plants by the enhanced contents of low-molecular antioxidants (proline, non-protein thiols, ascorbic acid, phenolic compounds) and activities of superoxide dismutase, catalase, ascorbate peroxidase, and glutathione peroxidase. The strongest positive correlation was detected between the content of malondialdehyde and contents of proline (r = 0.89–0.95, p ≤ 0.05) and phenolic compounds (r = 0.90–0.94, p ≤ 0.05) as well as superoxide dismutase activity (r = 0.81–0.90, p ≤ 0.05). Based on the results of a comprehensive analysis of growth and biochemical parameters and of the cluster analysis, Valdai variety proved to be more resistant to oil pollution. Due to this, Valdai variety is considered to be a promising rye variety for cultivation on moderately oil-polluted soils in order to decontaminate them. At the same time, it is necessary to conduct further studies aimed at investigating oil transformation processes in the soil-rye system, which would make it possible to determine the efficiency of using this cereal for soil remediation.

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