Academic literature on the topic 'Additive combinatory'
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Journal articles on the topic "Additive combinatory":
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Bimbó, Katalin. "The Church-Rosser property in dual combinatory logic." Journal of Symbolic Logic 68, no. 1 (March 2003): 132–52. http://dx.doi.org/10.2178/jsl/1045861508.
Abstract:
AbstractDual combinators emerge from the aim of assigning formulas containing ← as types to combinators. This paper investigates formally some of the properties of combinatory systems that include both combinators and dual combinators. Although the addition of dual combinators to a combinatory system does not affect the unique decomposition of terms, it turns out that some terms might be redexes in two ways (with a combinator as its head, and with a dual combinator as its head). We prove a general theorem stating that no dual combinatory system possesses the Church-Rosser property. Although the lack of confluence might be problematic in some cases, it is not a problem per se. In particular, we show that no damage is inflicted upon the structurally free logics, the system in which dual combinators first appeared.
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Erdmann, Kati, Jessica Ringel, Silke Hampel, Manfred P. Wirth, and Susanne Fuessel. "Carbon nanomaterials sensitize prostate cancer cells to docetaxel and mitomycin C via induction of apoptosis and inhibition of proliferation." Beilstein Journal of Nanotechnology 8 (June 23, 2017): 1307–17. http://dx.doi.org/10.3762/bjnano.8.132.
Abstract:
We have previously shown that carbon nanofibers (CNFs) and carbon nanotubes (CNTs) can sensitize prostate cancer (PCa) cells to platinum-based chemotherapeutics. In order to further verify this concept and to avoid a bias, the present study investigates the chemosensitizing potential of CNFs and CNTs to the conventional chemotherapeutics docetaxel (DTX) and mitomycin C (MMC), which have different molecular structures and mechanisms of action than platinum-based chemotherapeutics. DU-145 PCa cells were treated with DTX and MMC alone or in combination with the carbon nanomaterials. The impact of the monotreatments and the combinatory treatments on cellular function was then systematically analyzed by using different experimental approaches (viability, short-term and long-term proliferation, cell death rate). DTX and MMC alone reduced the viability of PCa cells to 94% and 68%, respectively, whereas a combined treatment with CNFs led to less than 30% remaining viable cells. Up to 17- and 7-fold higher DTX and MMC concentrations were needed in order to evoke a similar inhibition of viability as mediated by the combinatory treatments. In contrast, the dose of platinum-based chemotherapeutics could only be reduced by up to 3-fold by combination with carbon nanomaterials. Furthermore, combinatory treatments with CNFs led mostly to an additive inhibition of short- and long-term proliferation compared to the individual treatments. Also, higher cell death rates were observed in combinatory treatments than in monotreatments, e.g., a combination of MMC and CNFs more than doubled the cell death rate mediated by apoptosis. Combinations with CNTs showed a similar, but less pronounced impact on cellular functions. In summary, carbon nanomaterials in combination with DTX and MMC evoked additive to partly synergistic anti-tumor effects. CNFs and CNTs possess the ability to sensitize cancer cells to a wide range of structurally diverse chemotherapeutics and thus represent an interesting option for the development of multimodal cancer therapies. Co-administration of chemotherapeutics with carbon nanomaterials could result in a reduction of the chemotherapeutic dosage and thus limit systemic side effects.
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Netopilova, Marie, Marketa Houdkova, Klara Urbanova, Johana Rondevaldova, and Ladislav Kokoska. "Validation of Qualitative Broth Volatilization Checkerboard Method for Testing of Essential Oils: Dual-Column GC–FID/MS Analysis and In Vitro Combinatory Antimicrobial Effect of Origanum vulgare and Thymus vulgaris against Staphylococcus aureus in Liquid and Vapor Phases." Plants 10, no. 2 (February 18, 2021): 393. http://dx.doi.org/10.3390/plants10020393.
Abstract:
Combinatory action of antimicrobial agents such as essential oils (EOs) show to be an effective strategy to overcome the problem with increasing antibiotic resistance of microorganisms, including Staphylococcus aureus. The objective of this study was to evaluate in vitro antimicrobial interactions between Origanum vulgare and Thymus vulgaris EOs against various S.aureus strains in both liquid and vapor phases using the broth volatilization checkerboard method. Fractional inhibitory concentrations (FICs) were determined for both liquid and vapor phases, and the composition of EOs was analyzed by gas chromatography-mass spectrometry using dual-column/dual-detector gas chromatograph. Results of oregano and thyme EOs combination showed additive effects against all S. aureus strains in both phases. In several cases, sums of FICs were lower than 0.6, which can be considered a strong additive interaction. The lowest FICs obtained were 0.53 in the liquid phase and 0.59 in the gaseous phase. Chemical analysis showed that both EOs were composed of many compounds, including carvacrol, thymol, γ-terpinene, and p-cymene. This is the first report on oregano and thyme EOs interactions against S. aureus in the vapor phase. It also confirms the accuracy of the broth volatilization checkerboard method for the evaluation of combinatory antimicrobial effects of EOs in the vapor phase.
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Yang, Shun-Kai, Khatijah Yusoff, Chun-Wai Mai, Wei-Meng Lim, Wai-Sum Yap, Swee-Hua Lim, and Kok-Song Lai. "Additivity vs Synergism: Investigation of the Additive Interaction of Cinnamon Bark Oil and Meropenem in Combinatory Therapy." Molecules 22, no. 11 (November 4, 2017): 1733. http://dx.doi.org/10.3390/molecules22111733.
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Dotti Sani, Giulia Maria, and Mario Quaranta. "A Mixed Approach to the Work-Motherhood Relation: An Application of Fuzzy Set Qualitative Comparative Analysis and Generalized Linear Models." Comparative Sociology 12, no. 1 (2013): 31–65. http://dx.doi.org/10.1163/15691330-12341251.
Abstract:
Abstract Female labor force participation and total fertility rates have been negatively correlated until the early ’80s. By the end of that decade, however, the relationship changed sign. Scholars have suggested a close link between individual reproductive behavior, labor market participation and institutional contexts, but we still lack clear evidence of the underlying micro-level mechanism. We propose the use of complementary techniques, fuzzy set Qualitative Comparative Analysis and Generalized Linear Models, as the different assumptions underlying the two, combinatory vs. additive, may lead to new insights on how the combination of institutional features can produce different outcomes in terms of the work-motherhood relationship.
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Bhattamisra, Subrat Kumar, Chew Hui Kuean, Lee Boon Chieh, Vivian Lee Yean Yan, Chin Koh Lee, Lee Peng Hooi, Lai Pei Shyan, Yun Khoon Liew, Mayuren Candasamy, and Priyadarshi Soumyaranjan Sahu. "Antibacterial Activity of Geraniol in Combination with Standard Antibiotics against Staphylococcus aureus, Escherichia coli and Helicobacter pylori." Natural Product Communications 13, no. 7 (July 2018): 1934578X1801300. http://dx.doi.org/10.1177/1934578x1801300701.
Abstract:
The antibacterial activity of geraniol and its effect in combination with ampicillin, amoxicillin and clarithromycin against Staphylococcus aureus, Escherichia coli and Helicobacter pylori was tested. The minimum inhibitory concentrations (MICs) and combinatory effects of geraniol against the bacteria were assessed by using the modified broth microdilution and checkerboard assay, respectively. The combinatory effect is expressed as fractional inhibitory concentration index (FICI). The MIC of geraniol against S. aureus, E. coli and H. pylori was found to be 11200, 5600, and 7325 μg/mL, respectively. A significant synergistic effect was observed with geraniol and ampicillin against S. aureus with FICI in the range 0.19 to 0.32. Geraniol and ampicillin exhibited a partial synergistic effect against E. coli. A similar effect was observed with geraniol and clarithromycin against S. aureus. A partial synergistic effect was observed with clarithromycin and geraniol against H. pylori with the FICI value in the range 0.86 to 0.89. An additive effect was observed with geraniol and amoxicillin combination against H. pylori. However, the amoxicillin and clarithromycin dose was reduced by thirty-two fold when combined with geraniol against H. pylori. The anti- H. pylori effect of geraniol with clarithromycin and amoxicillin could be of potential interest in the treatment of H. pylori infection and associated ulcers in humans. Further, geraniol, in combination with other antibiotics, has substantial therapeutic potential against S. aureus and E.coli infection.
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Sakaue, Saori, Masato Akiyama, Makoto Hirata, Koichi Matsuda, Yoshinori Murakami, Michiaki Kubo, Yoichiro Kamatani, and Yukinori Okada. "Functional variants in ADH1B and ALDH2 are non-additively associated with all-cause mortality in Japanese population." European Journal of Human Genetics 28, no. 3 (September 26, 2019): 378–82. http://dx.doi.org/10.1038/s41431-019-0518-y.
Abstract:
Abstract The functional variants involved in alcohol metabolism, the A allele of rs1229984:A > G in ADH1B and the A allele of rs671:G > A in ALDH2, are specifically prevalent among East Asian population. They are shown to be under recent positive selection, but the reasons for the selection are unknown. To test whether these positively selected variants have beneficial effects on survival in modern population, we performed the survival analyses using the large-scale Japanese cohort (n = 135,974) with genotype and follow-up survival data. The rs671-A allele was significantly associated with the better survival in the additive model (HR for mortality = 0.960, P = 1.7 × 10−5), and the rs1229984-A had both additive and non-additive effects (HR = 0.962, P = 0.0016 and HR = 0.958, P = 0.0066, respectively), which was consistent with the positive selection. The favorable effects of these alleles on survival were independent of the habit of alcohol consumption itself. The heterogenous combinatory effect between rs1229984 and rs671 genotype was also observed (HRs for AA genotype at rs671 were 1.03, 0.80, and 0.90 for GG, GA, and AA genotype at rs1229984, respectively), supposedly reflecting the synergistic effects on survival.
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Villalobos-González, Antonio, Ignacio Benítez-Riquelme, Fernando Castillo-González, Ma del Carmen Mendoza-Castillo, and Alejandro Espinosa-Calderón. "Genetic Parameters in Mesocotyl Elongation and Principal Components for Corn in High Valleys, Mexico." Seeds 3, no. 1 (March 13, 2024): 149–68. http://dx.doi.org/10.3390/seeds3010012.
Abstract:
Corn germplasm with different mesocotyl elongation was characterized for High Valleys in Mexico by estimating the general combinatory aptitude (GCA), specific combinatory aptitude (SCA), heterosis (H), inbreeding depression (ID) and principal component aptitude (PCA), with the purpose of directing the improvement for deep sowing. The hypothesis was that the parents and crosses of mesocotyl present variability in seedling and adult plant traits based on deep sowing. The 36 F1 and F2 crosses—derived from nine parents, three with short mesocotyl (S), three medium (M) and three long (L), obtained through Griffing diallel II—plus the parents were planted in sand beds and polyethylene bags in a greenhouse during the spring–summer cycles of 2021 and 2022. The following traits were measured: length of mesocotyl (LM), length of coleoptile, total seedling dry matter and 10 cob traits in addition to total dry matter. In 11 of the 14 traits, there was a positive and significant correlation (p ≤ 0.05) between the GCA of the parents and their LM. The highest SCA, H and ID (p ≤ 0.05) were for crosses L × L for all the traits measured. When comparing the GCA/SCA proportions, this relation varied from 0.76 to 0.97, which points to practically equal additive effects with those of dominance; however, in parents and L × L crosses, this relation was on average 0.94, 1.07 in M × M, 0.22 in S × S and 0.36 in L × S. In both F1 and F2, the variation was explained by two principal components: 89.5% for GCA and 73.4% for SCA. In both generations, the parents with higher GCA were H-48, HS-2 and Promesa, the three with long mesocotyl, while those with the highest GCA were crosses between these three hybrids.
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Miklasińska-Majdanik, Maria, Małgorzata Kępa, Tomasz J. Wąsik, Karolina Zapletal-Pudełko, Magdalena Klim, and Robert D. Wojtyczka. "The Direction of the Antibacterial Effect of Rutin Hydrate and Amikacin." Antibiotics 12, no. 9 (September 21, 2023): 1469. http://dx.doi.org/10.3390/antibiotics12091469.
Abstract:
The aim of the presented study was to examine the in vitro antimicrobial activity of rutin hydrate (RH) alone and in combination with amikacin against 12 reference strains of Gram-positive and Gram-negative bacteria. The antibacterial activity assay was evaluated in the concentration range of 2–2048 µg/mL. A serial microdilution method was used to determine the minimal inhibitory concentration (MIC) of the examined compound against reference strains. RH showed varying potential against the tested strains with MICs ranging from 128 to 1024 µg/mL. In order to examine the combinatory profile of RH and amikacin, the fractional inhibitory concentrations (FICs) were determined. The RH–amikacin combination was more active against Gram-negative bacteria where four synergism and two additive interactions were noted. For four out of six Gram-positive isolates, an indifferent effect of RH and amikacin was demonstrated, and for two strains, the tested combination had an additive effect. The results of this study showed that RH possesses antimicrobial potential in vitro towards the tested reference isolates. Moreover, it shows a promising combined effect with amikacin against Gram-negative bacteria.
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Muñoz Romero, Luis Ángel, Enrique Navarro Guerrero, Manuel De la Rosa Ibarra, Luis Pérez Romero, and Ángel Enrique Caamal Dzul. "Estimación de varianzas genéticas en ocho variedades criollas de maíz para el Bajío mexicano." Agronomía Mesoamericana 28, no. 2 (April 30, 2017): 455. http://dx.doi.org/10.15517/ma.v28i2.21801.
Abstract:
The aim of this work was to estimate the combinatory aptitude, genetic variance and heterosis of eight creole corn varieties. The research work was carried in Irapuato, Guanajuato, México, during 2008 and 2009. A randomized complete block design with three replications was used to evaluate the twenty-eight crosses under method 4 Griffing (1956). Each experimental plot included four rows five meters long with a separation of 0,75 m. The general combing ability and specific (ACG and ACE) were highly significant (P<0.01) for all traits except flowering days. The dominance variance (σ2D) was larger and more important than additive variance (σ2A) for most of the traits, indicating that non- additive genetic genes were important on the expression of those traits on crosses. It was observed that varieties P6 (creole #5), P7 (creole #2) and P8 (creole San Antonio) had larger variance effects (σ2ACE) for long cob, number of rows per cob, total cob number, and grain yield. Some outstanding crosses were identified for their high grain yield as well as heterosis, mainly those that included germoplasm of creole #5, #2 and San Antonio. According to the aforementioned we recommend to draw lines from the above populations and cross them to produce hybrids.
Dissertations / Theses on the topic "Additive combinatory":
1
Riblet, Robin. "Ensembles de petite somme et ensembles de Sidon, étude de deux extrêmes." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0127.
Abstract:
Notre projet se situe dans le domaine de la combinatoire additive. Il s’agit plus précisément de déterminer la taille maximale d’un sous-ensemble A d’un groupe fini G qui ne contient pas de triplets (a,a+d,a+2d) d’éléments distincts. On dit alors que A est sans progression arithmétique. Une telle progression (PA3) est en fait un exemple à la fois simple et naturel de structure additive que l’on s’attend à trouver dans un ensemble « assez gros ». Toute la difficulté consiste à déterminer ce que « assez gros » signifie ici. La recherche de la taille maximale d’un ensemble sans progression arithmétique est un problème désormais classique en combinatoire additive. Elle a donné lieu à des travaux célèbres des meilleurs spécialistes du domaine. On distingue deux aspects du problème : la détermination d’une taille au-delà de laquelle on est assuré que A possède des PA3, ce qui donne une majoration de la taille maximale d’un ensemble sans PA3, et la construction de gros ensembles sans PA3, ce qui en donne une minoration. Nous insisterons plus particulièrement sur la construction d’ensembles sans PA3 dans les groupes finis Z_q^n avec q petit. On commencera par une optimisation numérique des ensembles de base utilisés dans les constructions déjà connues et une généralisation à d’autres entiers q. On cherchera également à adapter une construction de Ruzsa à ce contexte. Cela permettra d‘aborder les difficultés de manière progressive en commençant par des manipulations combinatoires sur un groupe de base de petit cardinal autorisant donc une approche numériqueOur project lies in the field of additive combinatorics. More precisely, we seek the maximal size of a progression free subset of a finite group G, meaning a subset with no three distinct elements of the form a, a+d, a+2d (called a 3AP for 3 arithmetic progression). A 3AP is a simple and natural pattern that we expect to find in a 'large enough' set and we shall try to precise what 'large enough' means here. Trying to determine the maximal size of a progression free set is now a classical problem in additive combinatorics, on which many of the best experts have worked. There are two different aspects in this problem : to determine a minimal size for A which assures the existence of 3AP in A, this gives an upper bound for the maximal size of a progression free set; to build some large progression free sets, this gives a lower bound for this maximal size. We will insist on the constructive part in the context of groups Z_q^n with small q. We shall also try to adapt a construction by Ruzsa to this context. The progression of this work should be from some combinatorial constructions, allowing numerical approach, to more theoretical concepts
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Liétard, Florian. "Évitabilité de puissances additives en combinatoire des mots." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0259.
Abstract:
Ce document est principalement consacré à l'étude de l'évitabilité des cubes additifs dans les points fixes de morphismes. Les problèmes d'évitabilité des puissances additives sont connus pour avoir des implications dans la théorie des semi-groupes. Depuis un article publié en 2013 par J. Cassaigne, J.D. Currie, L. Schaeffer et J.O. Shallit, nous savons qu'il est possible de construire sur l'alphabet {0,1,3,4} un mot infini qui évite les cubes additifs, i.e., un mot qui ne contient pas trois facteurs consécutifs de même taille et même somme. Nous commençons par expliquer notre démarche de recherche avec cet article comme point de départ et par discuter des similarités entre les différents morphismes permettant d'éviter les cubes additifs sur des alphabets de 4 lettres. Nous expliciterons la façon dont nous avons programmé en C++ la recherche de morphismes créant des mots infinis sans puissances additives. Nous étendons ensuite la preuve de l'article de 2013 à un ensemble infini de morphismes (correspondant à une classe d'équivalence). Après l'étude d'un exemple nous développons une démonstration basée sur des substitutions entre les morphismes. Le résultat principal de ce document est qu'il est possible de donner, sur chaque alphabet de 4 lettres qui ne soit pas une transformation affine de {0,1,2,3}, un morphisme explicite possédant un point fixe infini sans cubes additifs. Ce travail, effectué en collaboration avec Matthieu Rosenfeld, a donné lieu à la publication d'un article. Pour démontrer ce résultat nous utilisons un argument contenu dans l'article de 2013, des majorations effectuées après disjonction des cas et des arguments de symétries entre les alphabets. Enfin, nous nous intéressons à l'évitabilité des cubes additifs sur {0,1,2,3} afin de tenter de répondre à une question posée en 2018 par M. Rao et M. Rosenfeld. Cet alphabet est le seul de quatre lettres pour lequel notre résultat principal n'apporte pas de réponse. Nous représentons graphiquement les mots possédant des puissances additives et nous développons deux programmes informatiques parallélisés. Le premier permet de détecter efficacement les puissances additives dans un mot très long, le second permet de créer un mot de plus de 70 millions de lettres sans cube additif sur {0,1,2,3}. Nous améliorons ainsi significativement la précédente borne connue (1.4x 10^5). Pour parvenir à ce résultat nous inversons périodiquement l'ordre de priorité pour le choix des lettres dans la construction du mot comme nous le suggéraient les représentations graphiques. Nos programmes utilisent des approches à la fois multi-ordinateurs et multi-threads pour gagner en efficacitéThe present thesis is dedicated to the various aspects of the problem of avoiding additive cubes in the fixed points of morphisms. Problems concerning the avoidability of additive powers are closely related to questions in the theory of semigroups. Since the publication of the article of J. Cassaigne, J.D. Currie, L. Schaeffer and J.O. Shallit (2013) we know that it is possible to construct an infinite word over {0, 1 ,3, 4} that avoids additive cubes, i.e., a word that avoids three consecutive blocks of same size and same sum. We first explain the methods used by the authors in their article, and then use it as a starting point for our discussions, with the ultimate aim to clarify the various similarities and connections between the different morphisms that allow to avoid additive cubes on alphabets over 4 letters. We next discuss our implementation in C++ of the investigation of theses morphisms, and then proceed to give an infinite family of morphisms (corresponding to classes of equivalence) that avoid additive cubes. After this investigation, we give a general proof scheme that is based on substitutions between morphisms. The main result of the thesis is that for any alphabet of 4 letters, with the sole exception of the alphabet {0, 1 ,2, 3} and its affine transformations, there is an explicit morphism whose infinite fixed point avoids additive cubes over the given alphabet. This work has been carried out in collaboration with Matthieu Rosenfeld and gave rise to an article in a peer-reviewed journal. In order to show this result, we use arguments from the article of Cassaigne et al., several numerical estimates for the underlying quantities, case disjunction as well as symmetry considerations for the alphabets under consideration. In the final part of the thesis we then study the question of avoiding additive cubes over {0, 1 ,2, 3} with the hope to answer a question posed by M. Rao and M. Rosenfeld in 2018. This alphabet is the only 4-letters alphabet where our result does not apply. We first study by graphical means the words that contain additive powers, and we discuss and implement in a second step two parallelized computer programs. The first program detects in an efficient way the occurrence of additive powers in very long words, whereas the second one allows to create long words over {0, 1 ,2, 3} without introducing any additive cube. With the help of these programs, we obtain a word of over 70 million letters that avoids additive cubes over {0, 1 ,2, 3}. This largely improves on the former known bound (1.4 x 10^5). To obtain our result, as suggested by our graphical considerations, we periodically reverse the order of priority for the choice of the letters in the construction of our word. Our programs use multi-computers and multi-threads settings to gain considerably on efficiency
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Lambert, Victor. "Quelques problèmes additifs : bases, pseudo-puissances et ensembles k-libres." Palaiseau, Ecole polytechnique, 2015. https://theses.hal.science/tel-01174654/document.
Abstract:
Habituellement étudié dans N ou Z, on s'intéresse aux bases additives dans les groupes abéliens infinis. On obtient des résultats sur les fonctions E, X et S, qui caractérisent le comportement d'une base lorsqu'on lui enlève un élément. On étudie également l'ensemble A des pseudo-puissances s-ièmes. Celles-ci forment presque sûrement une base additive d'ordre s+1. On cherche à affiner ce résultat en déterminant des compléments additifs de sA de taille minimale, c'est-à-dire des ensembles B tels que sA+B contient presque sûrement tout entier suffisamment grand. Enfin, nous montrons quelle est la taille maximale d'un ensemble k-libre dans Z/nZ. La contrainte modulaire joue ici un rôle prépondérant. Les méthodes employées sont très différentes, selon la relation arithmétique entre k et n. En particulier, nous démontrons un résultat sur des arbres combinatoires, dans l'étude du cas généralWidely studied in N or Z, we are interested in additive bases in infinite abelian groups. We get some results about the functions E, X and S, which caracterize the behaviour of a basis when we remove an element. We also study the set A of pseudo s-th powers, which is an additive basis of order s+1. We wonder what is the minimal size of an additive complement of sA, that is a set B such that sA+B contains all large enough integers. With respect to this problem, we prove quite precise theorems which are tantamount to asserting that a threshold phenomenon occurs. Finally, we establish the maximal size of a k-free set in Z/nZ. The study of this quantity strongly depends on the arithmetical relative properties of n and k. That is why we use different methods depending on cases. In particular, we show a result on combinatorial trees for the general case
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Monopoli, F. "SUMSETS AND CARRIES IN CYCLIC GROUPS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/342841.
Abstract:
This thesis studies some direct and inverse problems concerning sumsets in cyclic groups, with applications to the study of carries. First of all we prove a generalization of the classical Cauchy-Davenport inequality in finite cyclic groups, thus bounding the cardinality of sumsets of sets satisfying certain density properties by a function linked to the arithmetic progression structure of the summands. This allows us to prove that digital sets modulo a generic integer which induce a minimal amount of distinct carries must be arithmetic progressions. After proving an inverse theorem for Pollard's inequality for sets with the Chowla property, we prove moreover that digital sets always induce carries with frequency asymptotically greater than 1/4. The last part of the thesis is devoted to the study of generalized sumsets, and contains various direct and inverse theorems for these objects in different ambient groups.
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Tringali, Salvatore. "Some questions in combinatorial and elementary number theory." Phd thesis, Université Jean Monnet - Saint-Etienne, 2013. http://tel.archives-ouvertes.fr/tel-01060871.
Abstract:
This thesis is divided into two parts. Part I is about additive combinatorics. Part II deals with questions in elementary number theory. In Chapter 1, we generalize the Davenport transform to prove that if si S\mathbb A=(A, +)S is acancellative semigroup (either abelian or not) and SX, YS are non-empty subsets of SAS such that the subsemigroup generated by SYS is abelian, then SS|X+Y|\gc\min(\gamma(Y, |X|+|Y|-I)SS, where for SZ\subsetcq AS we let S\gamma(Z):=\sup_{z_0\in Z^\times}\in f_(z_0\nc z\inZ) (vm ord)(z-z_0)S. This implies an extension of Chowla's and Pillai's theorems for cyclic groups and a stronger version of an addition theorem by Hamidoune and Karolyi for arbitrary groups. In Chapter 2, we show that if S(A, +) is a cancellative semigroup and SX, Y\subsetcq AS then SS|X+Y|\gc\min(\gammaX+Y), |X|+|Y|-I)SS. This gives a generalization of Kemperman's inequality for torsion free groups and a stronger version of the Hamidoune-Karolyi theorem. In Chapter 3, we generalize results by Freiman et al. by proving that if S(A,\ctlot)S is a linearly orderable semigroup and SSS is a finite subset of SAS generating a non-abelian subsemigroup, then S|S^2-\gc3|S|-2S. In Chapter 4, we prove results related to conjecture by Gyory and Smyth on the sets SR_k^\pm(a,b)S of all positive integers SnS such that Sn^kS divides Sa^a \pmb^nS for fixed integers SaS, SbS and SkS with Sk\gc3S, S|ab|\gc2Set S\gcd(a,b) = 1S. In particular, we show that SR_k^pm(a,b)S is finite if Sk\gc\max(|a|.|b|)S. In Chapter 5, we consider a question on primes and divisibility somchow related to Znam's problem and the Agoh-Giuga conjecture
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Oosting, Peter. "Bicyclic Tramadol analogues : towards a structure-activity relationship." Bordeaux 1, 2007. http://www.theses.fr/2007BOR13413.
Abstract:
Le traitement de la douleur est un domaine d'importance croissante dans la médecine. Pour les douleurs sévères, les opiacés restent parmi les médicaments les plus utilisés, mais ils présent cependant des effets secondaires sérieux, c'est pourquoi les chercheurs continuent à développer de nouveaux analgésiques. Le Tramadol, un opiacé partiel avec un mécanisme particulier, n'induit pas les effets secondaires associés avec la plupart des opiacés. Il a été utilisé durant des années pour le traitement des douleurs modérées et sévères. Cette thèse décrit la synthèse de composés dérivés du Tramadol, ainsi que leur activité biologique. Plus précisément, des dérivés bicycliques possédant les mêmes groupements pharmacophores que le Tramadol ont été synthétisés. Des composés possédant des cycles de taille différente ont été obtenus. Certains dérivés ont été davantage fonctionnalisés en utiliant des réactions d'hydrogénation, de dihydrowylation et d'owygénation. En outre, certains produits ont été soumis à des réactions utilisant l'approche combinatoire. Ainsi, des réactions de type Grignard ont été effectuées avec un robot, dans le but de découvrir, par hasard, des composés intéressants. Les deux approches ont mené à des produits qui possèdent une activité biologique. Ces données biologiques ont été utilisées dans une étude de modélisation moléculaire afin de découvrir de nouvelles cibles. Les expériences de "Docking" sur le récepteur u ont permis d'identifier quelques composés intéressants, malheuresement la synthèse de l'un de ces composés a échoué en raison de problèmes d'hydrolyse d'une fonction cétal. A la fin de ces travaux, une synthèse a été proposée qui permettra vraisemblablement d'obtenir le composé désiré.
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Biswas, Arindam. "Théorie des groupes approximatifs et ses applications." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS573.
Abstract:
Dans la premier partie de cette thèse, nous étudions la structure des sous-groupes approximatifs dans les groupes metabéliens (groupes résolubles de classe de résolubilité 2) et montrons que si A est un tel sous-groupe K approximatif, il est K^⁰(r) contrôlée (au sens du Tao) par un groupe nilpotent où $ r désigne le rang de $ G=Fit (G) et Fit (G) $ est le sous-groupe de fitting de G. La deuxième partie est consacrée à l'étude de la croissance des ensembles dans GLn(Fq) où Fq est un corps fini. Nous montrons une borne sur le diamètre (par rapport à n'importe quel système des générateurs) pour tous sous-groupes simples finis de ce groupe. Si G est un groupe fini simple de type Lie de rang n, et son corps de base est de taille borné, le diamètre du graphe du Cayley Gamma (G;S) serait borné par exp (O (n (log n) ^ 3)) . Si la taille du corps fini Fq n'est pas borné, notre méthode donne une borne de q ^ {O (n ( log nq) ^ 3) pour le diamètre.Dans la troisième partie nous nous sommes intéressés à la croissance des ensembles dans les boucles de Moufang commutatifs. Ceux-ci sont les boucles commutatifs respectant les identités de Moufang mais sans être (nécessairement) associatifs. Nous montrons que, si les tailles des ensembles des associateurs sont bornées alors la croissance des sous-structures approximatifs dans ces boucles est similaire à celle des groupes ordinaires. De cette façon dans le cadre des boucles de moufang commutatifs finiment engendré on a un théorème de structure pour ses sous-boucles approximatifs.Mots-clefs -sous-groupes approximatifs, groupes résolubles, diamètres des groupes, boucles de moufang commutatifsIn the first part of this thesis, we study the structure of approximate subgroups inside metabelian groups (solvable groups of derived length 2) and show that if A is such a K-approximate subgroup, then it is K^(O(r)) controlled (in the sense of Tao) by a nilpotent group where r denotes the rank of G=Fit(G) and Fit(G) is the fitting subgroup of G.The second part is devoted to the study of growth of sets inside GLn(Fq) , where we show a bound on the diameter (with respect to any set of generators) for all finite simple subgroups of this group. What we have is - if G is a finite simple group of Lie type with rank n, and its base field has bounded size, then the diameter of the Cayley graph C(G; S) would be bounded by exp(O(n(logn)^3)). If the size of the base field Fq is not bounded then our method gives a bound of q^(O(n(log nq)3)) for the diameter.In the third part we are interested in the growth of sets inside commutative Moufang loops which are commutative loops respecting the moufang identities but without (necessarily)being associative. For them we show that if the sizes of the associator sets are bounded then the growth of approximate substructures inside these loops is similar to those in ordinary groups. In this way for the subclass of finitely generated commutative moufang loops we have a classification theorem of its approximate subloops
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Verselder, Hélène. "Influence d’activations spatiales et motrices de polarités combinées sur le fonctionnement cognitif : effet de la synchronie-asynchronie temporelle et spatiale sur des combinatoires cognitives de nature mathématique." Thesis, Paris 10, 2017. http://www.theses.fr/2017PA100067.
Abstract:
De nombreuses études ont montré qu’une activation d'indices moteurs (mouvement d’approche ou de retrait ; Cretenet et Dru 2004) ou spatiaux (verticale ou horizontale ; Casasanto, 2009) était de nature à influencer un jugement ou des réponses finales. Dans le cadre des théories de la cognition incarnée, ce travail examine l’effet de l’activation synchrone ou asynchrone de ces indices comme étant révélatrice de processus cognitifs. Dans cette perspective, nos travaux, présentés sous la forme de deux articles, ont pour objectif d’analyser l’effet de ces activations, impliquant la théorie de la correspondance de polarité (Proctor et Cho, 2006), sur la résolution d’opérations arithmétiques, comme l’expression d’une combinatoire cognitive particulière. De plus, cette thèse supporte l’idée qu’une analogie entre la PCE et ces résultats peut être faite. En effet, le cœur de notre travail consiste défendre l’idée que quelque soit les indices conceptuels (motivationnel ou émotionnel) activés, de mêmes effets sont observés, traduisant la mise en jeu d’un même système de codage de polarités. Lors de l’activation d’indices de polarité (motivationnelle ou émotionnelle), un phénomène de compatibilité s’opère influençant le raisonnement mathématique.Nous proposons d'étudier l'effet d’un mouvement moteur (effectué) ou spatial (perçu) combinant deux dimensions spatiales (latérale et verticale) simultanément ou non sur la performance numérique. L’objectif est d’analyser l’influence de conditions de congruence ou de non congruence sur la résolution d’opérations arithmétiques. L’idée est de montrer qu’une activation synchrone d’indices moteurs ou spatiaux influencerait une combinatoire cognitive telle que la multiplication (Article 1) ; tandis qu’une activation asynchrone d’indices spatiaux influencerait une combinatoire cognitive telle que l’addition (Article 2).Ces travaux démontrent pour la première fois comment des combinatoires perceptives ou motrices déterminent des combinatoires cognitivesSeveral studies have shown that an activation of motors (approach-avoidance behaviors, Cretenet & Dru 2004) or spatial cues (vertical or horizontal, Casasanto, 2009) is likely to influence the affective judgment or the final responses. In regards of the theories of embodiment, this studies examine the effect of combined (synchronous or asynchronous) motor and spatial cues on mathematical reasoning as revealing cognitive processes. In this perspective, our work, presented in two articles, with the aim to analyze the effect of these activations, involving the theory of polarity correspondence (Proctor & Cho, 2006), on the resolution of arithmetic operations, as the expression of a particular cognitive functioning. Furthermore, this thesis supports the idea that this operation has some analogy with the polarity correspondence effect (PCE). Indeed, our work supports the idea that whatever the activated conceptual cues are (motivational or emotional), the same effects are observed - a similar system is activated, coded as polarities which might be indicative of the PCE. When the activation of polarity indices (motivational or emotional), a phenomenon of compatibility occurs that also influences mathematical reasoning.We investigate the effect of a motor (performed) or spatial (perceived) movement combining two spatial dimensions (laterality and verticality) simultaneously or not on numerical performance. The objective is to investigate the influence of congruence or noncongruence conditions on the resolution of arithmetic operations. When a synchronous activation of peripheral cues (motor or spatial) is activated, we would observed an effect on mathematical reasoning, such as multiplication (Article 1); while when an asynchronous activation, deferred in time and space, of spatial cues would influence a mathematical reasonning, such as addition (Article 2). For the first time, studies demonstrate how a particular combination of perceptual or motor activations reveals some correspondent cognitive mechanism
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Henriot, Kevin. "Structures linéaires dans les ensembles à faible densité." Thèse, Paris 7, 2014. http://hdl.handle.net/1866/11116.
Abstract:
Réalisé en cotutelle avec l'Université Paris-Diderot.Nous présentons trois résultats en combinatoire additive, un domaine récent à la croisée de la combinatoire, l'analyse harmonique et la théorie analytique des nombres. Le thème unificateur de notre thèse est la détection de structures additives dans les ensembles arithmétiques à faible densité, avec un intérêt particulier pour les aspects quantitatifs. Notre première contribution est une estimation de densité améliorée pour le problème, initié entre autres par Bourgain, de trouver une longue progression arithmétique dans un ensemble somme triple. Notre deuxième résultat consiste en une généralisation des bornes de Sanders pour le théorème de Roth, du cas d'un ensemble dense dans les entiers à celui d'un ensemble à faible croissance additive dans un groupe abélien arbitraire. Finalement, nous étendons les meilleures bornes quantitatives connues pour le théorème de Roth dans les premiers, à tous les systèmes d'équations linéaires invariants par translation et de complexité un.
We present three results in additive combinatorics, a recent field at the interface of combinatorics, harmonic analysis and analytic number theory. The unifying theme in our thesis is the detection of additive structure in arithmetic sets of low density, with an emphasis on quantitative aspects. Our first contribution is an improved density estimate for the problem, initiated by Bourgain and others, of finding a long arithmetic progression in a triple sumset. Our second result is a generalization of Sanders' bounds for Roth's theorem from the dense setting, to the setting of small doubling in an arbitrary abelian group. Finally, we extend the best known quantitative results for Roth's theorem in the primes, to all translation-invariant systems of equations of complexity one.
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He, Weikun. "Sommes, produits et projections des ensembles discrétisés." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS335/document.
Abstract:
Dans le cadre discrétisé, la taille d'un ensemble à l'échelle δ est évaluée par son nombre de recouvrement par δ-boules (également connu sous le nom de l'entropie métrique). Dans cette thèse, nous étudions les propriétés combinatoires des ensembles discrétisés sous l'addition, la multiplication et les projections orthogonales. Il y a trois parties principales. Premièrement, nous démontrons un théorème somme-produit dans les algèbres de matrices, qui généralise un théorème somme-produit de Bourgain concernant l'anneau des réels. On améliore aussi des estimées somme-produit en dimension supérieure obtenues précédemment par Bougain et Gamburd. Deuxièmement, on étudie les projections orthogonales des sous-ensembles de l'espace euclidien et étend ainsi le théorème de projection discrétisé de Bourgain aux projections de rang supérieur. Enfin, dans un travail en commun avec Nicolas de Saxcé, nous démontrons un théorème produit dans les groupes de Lie parfaits. Ce dernier résultat généralise les travaux antérieurs de Bourgain-Gamburd et de SaxcéIn the discretized setting, the size of a set is measured by its covering number by δ-balls (a.k.a. metric entropy), where δ is the scale. In this document, we investigate combinatorial properties of discretized sets under addition, multiplication and orthogonal projection. There are three parts. First, we prove sum-product estimates in matrix algebras, generalizing Bourgain's sum-product theorem in the ring of real numbers and improving higher dimensional sum-product estimates previously obtained by Bourgain-Gamburd. Then, we study orthogonal projections of subsets in the Euclidean space, generalizing Bourgain's discretized projection theorem to higher rank situations. Finally, in a joint work with Nicolas de Saxcé, we prove a product theorem for perfect Lie groups, generalizing previous results of Bourgain-Gamburd and Saxcé
Book chapters on the topic "Additive combinatory":
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Eisenbrand, Friedrich, Naonori Kakimura, Thomas Rothvoß, and Laura Sanità. "Set Covering with Ordered Replacement: Additive and Multiplicative Gaps." In Integer Programming and Combinatoral Optimization, 170–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-20807-2_14.
Conference papers on the topic "Additive combinatory":
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Eranpurwala, Aliakbar, Seyedeh Elaheh Ghiasian, and Kemper Lewis. "Predicting Build Orientation of Additively Manufactured Parts With Mechanical Machining Features Using Deep Learning." In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22043.
Abstract:
Abstract Additive Manufacturing (AM) is a revolutionary development that is being viewed as a core technology for fabricating current and future engineered products. While AM has many advantages over subtractive manufacturing processes, one of the primary limitations of AM is to swiftly evaluate precise part build orientations. Current algorithms are either computationally expensive or provide multiple alternative orientations, requiring additional decision tradeoffs. To hasten the process of finding accurate part build orientation, a data-driven predictive model is introduced by mapping standard machining features to build orientation angles. A combinatory learning algorithm of classification and regression is utilized for the prediction of build orientation. The framework uses 54,000 voxelized standard tessellated language (STL) files as input to train the classification algorithm for eighteen standard machining features using a nine-layer 3D Convolutional Neural Network (CNN). Additionally, a multi-machining feature dataset of 1000 voxelized STL files are evaluated in parallel by performing quaternion rotations to obtain build orientation angles based on minimization of support structure volume. A regression model is then developed to establish a relationship between the machining features and orientation angles to predict optimal build orientation for new parts.