Journal articles: 'Polymorphic systems'

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Du, Dan, Guo-Bin Ren, Ming-Hui Qi, Zhong Li, and Xiao-Yong Xu. "Solvent-Mediated Polymorphic Transformation of Famoxadone from Form II to Form I in Several Mixed Solvent Systems." Crystals 9, no. 3 (March 20, 2019): 161. http://dx.doi.org/10.3390/cryst9030161.

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This paper discloses six polymorphs of famoxadone obtained from polymorph screening, which were characterized by XRPD, DSC, and SEM. A study of solvent-mediated polymorphic transformation (SMPT) of famoxadone from the metastable Form II to the stable Form I in several mixed solvent systems at the temperature of 30 °C was also conducted. The transformation process was monitored by Process Analytical Technologies. It was confirmed that the Form II to Form I polymorphic transformation is controlled by the Form I growth process. The transformation rate constants depended linearly on the solubility difference value between Form I and Form II. Furthermore, the hydrogen-bond-donation/acceptance ability and dipolar polarizability also had an effect on the rate of solvent-mediated polymorphic transformation.

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DELGADO, G., M. GUILLEN, and A. J. MORA. "4-METHYL HYPPURIC ACID: A CASE OF POLYMORPHISM AND SOLVATOMORPHISM." Periódico Tchê Química 16, no. 32 (August 20, 2019): 812–19. http://dx.doi.org/10.52571/ptq.v16.n32.2019.830_periodico32_pgs_812_819.pdf.

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Polymorphism is known as the ability of a solid material to exist in more than one form or crystal structure, with important applications in the preparation of active pharmaceutical ingredients. Characterization of different polymorphs of the specific metabolite of 4-xylene can contribute to the chemical and pharmaceutical industry. Polymorphism is of particular importance in industrial processes, where different physical properties of polymorphic forms can substantially alter the viability and quality of a manufactured product. This is particularly so for the design and production of drugs in the pharmaceutical industry, as varying physical properties between different polymorphs can affect shelf life and durability, solubility, as well as bioavailability and manufacturing of the drug. The crystallization, spectroscopic and X-ray diffraction characterization of two polymorph and one solvatomorph of 4-methylhippuric acid are presented. These compounds crystallizes in different crystalline systems. Polymorph I (4mH-I) crystalize in an orthorhombic cell with space group P212121. Polymorph II (4mHII) crystallizes in a monoclinic space group P21/c. Solvatomorph (4mH-S) crystallizes in a triclinic P-1 cell. All polymorphs crystallize in neutral form. The crystal packing of the three compounds are governed by hydrogen bonds intermolecular interactions of the type N--H···O and O--H···O forming tridimensional networks.

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Labine-Romain, Mackenzie, Sabrina Beckmann, Mohan Bhadbhade, Saroj Bhattacharyya, Michael Manefield, Christopher E. Marjo, and Anne M. Rich. "Polymorphs of Neutral Red, a Redox-Mediating Phenazine in Biological Systems." Australian Journal of Chemistry 70, no. 9 (2017): 1032. http://dx.doi.org/10.1071/ch17141.

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Neutral red 1 is a heterocyclic phenazine that, as a crystalline solid, has been observed to accelerate microbial methane generation from coal. Scale-up to an industrial process will require large quantities of neutral red crystals, hence an understanding of any polymorphic behaviour is essential for careful control of this process. A room-temperature structure of 1 (Form I) has been reported previously, and this study describes a new polymorph (Form II) crystallising from aqueous solution at 50°C, or transforming from Form I over an incubation time of one week at 70°C. Single-crystal X-ray diffraction has been used to study the molecular arrangements and intermolecular interactions in the new polymorph, and compared with those found in the room temperature form. Both polymorphs have been characterised using Raman and infrared spectroscopy, and a synthetic mixture of polymorphs successfully imaged using Raman spectroscopy. Raman imaging is proposed as a quality control method for small quantities of sample to ensure the correct polymorph is produced as a feedstock for this new methanogenesis process.

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Mnguni, Malitsatsi J., Joseph P. Michael, and Andreas Lemmerer. "Binary polymorphic cocrystals: an update on the available literature in the Cambridge Structural Database, including a new polymorph of the pharmaceutical 1:1 cocrystal theophylline–3,4-dihydroxybenzoic acid." Acta Crystallographica Section C Structural Chemistry 74, no. 6 (May 23, 2018): 715–20. http://dx.doi.org/10.1107/s2053229618006861.

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An analysis and classification of the 2925 neutral binary organic cocrystals in the Cambridge Structural Database is reported, focusing specifically on those both showing polymorphism and containing an active pharmaceutical ingredient (API). The search was confined to molecules having only C, H, N, O, S and halogens atoms. It was found that 400 out of 2925 cocrystals can be classified as pharmaceutical cocrystals, containing at least one API, and that of those, 56 can be classified as being polymorphic cocrystals. In general, the total number of polymorphic cocrystal systems of any type stands at 125. In addition, a new polymorph of the pharmaceutical cocrystal theophylline–3,4-dihydroxybenzoic acid (1/1), C7H8N4O2·C7H6O4, is reported.

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van den Ende, Joost, and Herma Cuppen. "Solid-to-solid polymorphic transitions in amino acid crystals." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1627. http://dx.doi.org/10.1107/s2053273314083727.

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The properties of crystals are related to their structure and therefore they can be different for different polymorphs. For example, the pharmaceutical characteristics bioavailability and shelf life can depend on the formed polymorph and its stability. We aim to understand transitions between polymorphs that occur in the solid phase, with the ultimate goal to induce or inhibit these transitions. We apply Molecular Dynamics (MD) simulations as a computational microscope to study these processes at the molecular level. Our used model systems for polymorphic behavior of molecular crystals in a pharmaceutical context are amino-acid crystals, in particular DL-norleucine. The polymorphs of DL-norleucine consist of tightly packed hydrogen-bonded bilayers with straight side chains that are weakly bound through Van-der-Waals interactions. When DL-norleucine undergoes a polymorphic transition, the bilayers shift with respect to each other. In the simulations of the enantiotropically-related beta and alpha polymorph, we observe that the transformed lattice parameters and molecular properties behave identically with temperature for both polymorphs. Consequently, the polymorphs only differ in the orientation of the molecular bilayers in the a'c' and the b'c'-plane, which explains the ease of transitions between them. Moreover, in simulations of the beta polymorph at 350 K we observe partial phase transitions which we could follow with the help of specifically designed order parameters. The transitions are exclusively occurring in the b'c'-plane. This indicates a possible transformation mechanism in which first shifts of bilayers occur in this plane, followed by shifts in the a'c'-plane. Interestingly, the region of highest flexibility of the molecule shifts from the middle to the end of the carbon chain at the highest studied temperature.

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6

Gordon, Colin S. "Polymorphic Iterable Sequential Effect Systems." ACM Transactions on Programming Languages and Systems 43, no. 1 (April 2021): 1–79. http://dx.doi.org/10.1145/3450272.

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Effect systems are lightweight extensions to type systems that can verify a wide range of important properties with modest developer burden. But our general understanding of effect systems is limited primarily to systems where the order of effects is irrelevant. Understanding such systems in terms of a semilattice of effects grounds understanding of the essential issues and provides guidance when designing new effect systems. By contrast, sequential effect systems—where the order of effects is important—lack an established algebraic structure on effects. We present an abstract polymorphic effect system parameterized by an effect quantale—an algebraic structure with well-defined properties that can model the effects of a range of existing sequential effect systems. We define effect quantales, derive useful properties, and show how they cleanly model a variety of known sequential effect systems. We show that for most effect quantales, there is an induced notion of iterating a sequential effect; that for systems we consider the derived iteration agrees with the manually designed iteration operators in prior work; and that this induced notion of iteration is as precise as possible when defined. We also position effect quantales with respect to work on categorical semantics for sequential effect systems, clarifying the distinctions between these systems and our own in the course of giving a thorough survey of these frameworks. Our derived iteration construct should generalize to these semantic structures, addressing limitations of that work. Finally, we consider the relationship between sequential effects and Kleene Algebras, where the latter may be used as instances of the former.

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7

Liu, Jie, and Wenfei Fan. "Polymorphic queries for P2P systems." Information Systems 36, no. 5 (July 2011): 825–42. http://dx.doi.org/10.1016/j.is.2011.01.001.

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8

GOTO, MATTHEW, RADHA JAGADEESAN, ALAN JEFFREY, CORIN PITCHER, and JAMES RIELY. "An extensible approach to session polymorphism." Mathematical Structures in Computer Science 26, no. 3 (February 23, 2015): 465–509. http://dx.doi.org/10.1017/s0960129514000231.

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Session types describe and constrain the input/output behaviour of systems. Existing session typing systems have limited support for polymorphism. For example, existing systems cannot provide the most general type for a generic proxy process that forwards messages between two channels. We provide a polymorphic session typing system for the π calculus, and demonstrate the utility of session-type-level functions in combination with polymorphic session typing. The type system guarantees subject reduction and safety properties, but not deadlock freedom. We describe a formalization of the type system in Coq. The proofs of subject reduction and safety properties, as well as typing of example processes, have been mechanically verified.

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9

Hoshizaki, Sugihiko. "Detection of isozyme polymorphism and estimation of geographic variation in the brown planthopper, Nilaparvata lugens (Homoptera: Delphacidae)." Bulletin of Entomological Research 84, no. 4 (December 1994): 503–8. http://dx.doi.org/10.1017/s0007485300032739.

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AbstractIsozyme polymorphism in the brown planthopper, Nilaparvata lugens (Stål) was investigated using isoelectric focusing. Four of the 18 enzyme systems assayed were polymorphic. Allelic designations could be made for two enzyme systems (PGM and AK), but not for GPI and IDH, and GPI seemed to be sex-linked. Using the two highly polymorphic enzyme systems, GPI and PGM, geographic variation was estimated among several Asian (except Japanese) laboratory populations and several Japanese wild populations. Significant variation was observed among the Asian (except Japanese) populations, but the genetic structures of Japanese populations were very similar to each other. These results are suggestive of substantial differentiation among Asian populations and large panmictic structure of the migrant population.

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10

Chauhan, Ravi, Ulya Sabeel, Alireza Izaddoost, and Shahram Shah Heydari. "Polymorphic Adversarial Cyberattacks Using WGAN." Journal of Cybersecurity and Privacy 1, no. 4 (December 12, 2021): 767–92. http://dx.doi.org/10.3390/jcp1040037.

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Intrusion Detection Systems (IDS) are essential components in preventing malicious traffic from penetrating networks and systems. Recently, these systems have been enhancing their detection ability using machine learning algorithms. This development also forces attackers to look for new methods for evading these advanced Intrusion Detection Systemss. Polymorphic attacks are among potential candidates that can bypass the pattern matching detection systems. To alleviate the danger of polymorphic attacks, the IDS must be trained with datasets that include these attacks. Generative Adversarial Network (GAN) is a method proven in generating adversarial data in the domain of multimedia processing, text, and voice, and can produce a high volume of test data that is indistinguishable from the original training data. In this paper, we propose a model to generate adversarial attacks using Wasserstein GAN (WGAN). The attack data synthesized using the proposed model can be used to train an IDS. To evaluate the trained IDS, we study several techniques for updating the attack feature profile for the generation of polymorphic data. Our results show that by continuously changing the attack profiles, defensive systems that use incremental learning will still be vulnerable to new attacks; meanwhile, their detection rates improve incrementally until the polymorphic attack exhausts its profile variables.

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11

Múdry, Pavol, and Bohuš Obert. "The Bioindicative Role of Enzyme Polymorphism of Seven Enzyme Systems as Reaction on High Cadmium Ions Concentration in Maize (Zea Mays L.)." Agriculture (Polnohospodárstvo) 57, no. 3 (October 1, 2011): 96–104. http://dx.doi.org/10.2478/v10207-011-0010-3.

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The Bioindicative Role of Enzyme Polymorphism of Seven Enzyme Systems as Reaction on High Cadmium Ions Concentration in Maize (Zea MaysL.)Effect of different concentrations of cadmium ions (0, 15, 60, 240 and 960 μmol dm-3in full Hoagland solutions) on enzyme polymorphism of seven enzymes - acid phosphatase (ACP), alcohol dehydrogenase (ADH), isocitrate dehydrogenase (IDH), malate dehydrogenase (MDH), 6-phosphogluconate dehydrogenase (PGD), phosphoglucoisomerase (PGI) and phosphoglucomutase (PGM) and their fifteen polymorphic loci - in coleoptiles, leaf blades and in the central parts of primary root systems of 14 days old seedlings in two self-pollinated maize lines and their single-cross was studied. Analyses of enzyme polymorphism showed that the biological material was homogeneous, self-pollinated lines had homozygous constitution in each analysed locus and hybrid had three loci (Acp1: 2/4, Idh2: 4/6andPgd1: 2/3.8) with heterozygous constitution. Ions of cadmium negatively influenced seedling growth and development, high cadmium concentration (960 μmol dm-3) was toxic and stopped further growth and development of maize seedlings after five days of cultivation. Enzyme fingerprint analysis of these fifteen polymorphic loci from selected enzymes supported their genotypic, organ and ontogenetic stability under high doses of cadmium ions. According to our results this group of enzymes in these polymorphic loci did not express changes in polymorphism after treatment with cadmium ions and thus cannot play the bioindicative role in this respect.

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12

Román, Gábor. "Inference of bounded L systems with polymorphic P systems." Journal of Membrane Computing 1, no. 1 (January 22, 2019): 52–57. http://dx.doi.org/10.1007/s41965-019-00007-0.

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13

Yan, Tingting, Dongyang Xi, Qiuxue Fang, Ye Zhang, Junhai Wang, and Xiaodan Wang. "High-Pressure Polymorphism in Hydrogen-Bonded Crystals: A Concise Review." Crystals 12, no. 5 (May 20, 2022): 739. http://dx.doi.org/10.3390/cryst12050739.

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High-pressure polymorphism is a developing interdisciplinary field. Pressure up to 20 GPa is a powerful thermodynamic parameter for the study and fabrication of hydrogen-bonded polymorphic systems. This review describes how pressure can be used to explore polymorphism and surveys the reports on examples of compounds that our group has studied at high pressures. Such studies have provided insight into the nature of structure–property relationships, which will enable crystal engineering to design crystals with desired architectures through hydrogen-bonded networks. Experimental methods are also briefly surveyed, along with two methods that have proven to be very helpful in the analysis of high-pressure polymorphs, namely, the ab initio pseudopotential plane–wave density functional method and using Hirshfeld surfaces to construct a graphical overview of intermolecular interactions.

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14

Guasmi, Ferdaous, Walid Elfalleh, Hédia Hannachi, Khadija Fères, Leila Touil, Nidhal Marzougui, Tebra Triki, and Ali Ferchichi. "The Use of ISSR and RAPD Markers for Genetic Diversity among South Tunisian Barley." ISRN Agronomy 2012 (January 3, 2012): 1–10. http://dx.doi.org/10.5402/2012/952196.

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Random amplified polymorphic DNA (RAPD) and intersimple sequence repeat (ISSR) were assayed to determine the genetic diversity of 80 barley specimens from South Tunisia. The ISSR primers showed variation in the percentage of polymorphism, band informativeness (Ib), and resolving power (Rp). The percentage of polymorphism is 66.67%, the average Ib ranged from 0.24 to 0.39, while Rp ranged from 0.74 to 1.16. In RAPD analysis, three primers yielded a total of 17 scorable bands, which are all polymorphic. The three polymorphic primers exhibited variation with regard to average band informativeness (AvIb) and resolving power (Rp). RAPD and ISSR marker systems were found to be useful for the genetic diversity among the barley specimens. The two dendrograms obtained through these markers show different clustering of 80 barely specimens, but we noted that some clusters were similar in some cases. A poor correlation () was found between both sets of genetic similarity data, suggesting that both sets of markers revealed unrelated estimates of genetic relationships. Therefore, the ISSR and RAPD molecular markers show two genetic grouping of studied barely specimens.

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15

Gui, Yue, Chengbin Huang, Chenyang Shi, Torsten Stelzer, Geoff G. Z. Zhang, and Lian Yu. "Polymorphic selectivity in crystal nucleation." Journal of Chemical Physics 156, no. 14 (April 14, 2022): 144504. http://dx.doi.org/10.1063/5.0086308.

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Crystal nucleation rates have been measured in the supercooled melts of two richly polymorphic glass-forming liquids: ROY and nifedipine (NIF). ROY or 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile is known for its crystals of red, orange, and yellow colors and many polymorphs of solved structures (12). Of the many polymorphs, ON (orange needles) nucleates the fastest with the runner up (Y04) trailing by a factor of 103 when compared under the same mobility-limited condition, while the other unobserved polymorphs are slower yet by at least 5 orders of magnitude. Similarly, of the six polymorphs of NIF, [Formula: see text]′ nucleates the fastest, [Formula: see text]′ is slower by a factor of 10, and the rest are slower yet by at least 5 decades. In both systems, the faster-nucleating polymorphs are not built from the lowest-energy conformers, while they tend to have higher energies and lower densities and thus greater similarity to the liquid phase by these measures. The temperature ranges of this study covered the glass transition temperature Tg of each system, and we find no evidence that the nucleation rate is sensitive to the passage of Tg. At the lowest temperatures investigated, the rates of nucleation and growth are proportional to each other, indicating that a similar kinetic barrier controls both processes. The classical nucleation theory provides an accurate description of the observed nucleation rates if the crystal growth rate is used to describe the kinetic barrier for nucleation. The quantitative rates of both nucleation and growth for the competing polymorphs enable prediction of the overall rate of crystallization and its polymorphic outcome.

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Dornic, Vincent, Pierre Jouvelot, and David K. Gifford. "Polymorphic time systems for estimating program complexity." ACM Letters on Programming Languages and Systems 1, no. 1 (March 1992): 33–45. http://dx.doi.org/10.1145/130616.130620.

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17

McClay, Joseph L., and Edwin J. C. G. van den Oord. "Variance component analysis of polymorphic metabolic systems." Journal of Theoretical Biology 240, no. 1 (May 2006): 149–59. http://dx.doi.org/10.1016/j.jtbi.2005.09.011.

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18

Rajendrakumar, Satyasree, Anuja Surampudi Venkata Sai Durga, and Sridhar Balasubramanian. "Strategic synthon approach in obtaining cocrystals and cocrystal polymorphs of a high-Z′ system deferiprone – an anti-thalassemia drug." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 77, no. 6 (November 12, 2021): 946–64. http://dx.doi.org/10.1107/s205252062100980x.

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Compounds with more than one molecule in the crystallographic asymmetric unit (Z′ > 1) display a noticeably stronger propensity to form cocrystals. Deferiprone is an anti-thalassemia drug known to exhibit polymorphic behaviour. Previously, three polymorphs were reported out of which one of them exhibited Z′ > 1. In the present manuscript, a fourth polymorph of deferiprone was identified and it also possessed Z′ > 1. All the four polymorphs showed similar hydrogen bonding features and differed in crystal packing. The ability of deferiprone to crystallize as Z′ > 1 prompted us to investigate the hydrogen bonding and synthon variation upon cocrystallization of deferiprone with hydroxyl-group-containing coformers such as catechol, hydroquinone, phloroglucinol, resorcinol and pyrogallol. Crystallization attempts along with PXRD analysis aided in obtaining 11 new cocrystal structures which involve different stoichiometric cocrystals and some polymorphs. Synthon analysis, crystal packing as well as thermal behaviour were assessed and compared. The presence of multiple phases in each cocrystal system in its respective bulk powders was identified and quantified using PXRD and Rietveld analysis. Homosynthons were observed in three co-crystal systems, while a heterosynthon was observed in five systems. The combination of both homo- and heterosynthon was observed in three cocrystal systems. The phase transformation events were observed in most of the systems. In nine co-crystal systems, the melting points were observed intermediate between those of the API and the coformers.

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19

Shishkina, Svitlana V., Irina S. Konovalova, Pavlo V. Trostianko, Anna O. Geleverya, Sergiy M. Kovalenko, and Natalya D. Bunyatyan. "Three polymorphs of 3-(3-phenyl-1H-1,2,4-triazol-5-yl)-2H-1-benzopyran-2-one formed from different solvents." Acta Crystallographica Section C Structural Chemistry 75, no. 6 (May 29, 2019): 822–32. http://dx.doi.org/10.1107/s2053229619006405.

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The polymorphic study of 3-(3-phenyl-1H-1,2,4-triazol-5-yl)-2H-1-benzopyran-2-one, C17H11N3O2, was performed due to its potential biological activity and revealed three polymorphic modifications in the triclinic space group P\overline{1}, the monoclinic space group P21 and the orthorhombic space group Pbca. These polymorphs have a one-column layered type of crystal organization. The strongest interactions between the molecules of the studied structures is stacking between π-systems, while N—H...N and C—H...O hydrogen bonds link stacked columns forming layers as a secondary basic structural motif. C—H...π hydrogen bonds were observed between neighbouring layers and their role is the least significant in the formation of the crystal structure. Packing differences between the polymorphic modifications are minor and can be identified only using an analysis based on a comparison of the pairwise interaction energies.

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20

Čolić, S., D. Milatović, D. Nikolić, and G. Zec. "Isoenzyme polymorphism of almond genotypes selected in the region of northern Serbia." Horticultural Science 37, No. 2 (May 6, 2010): 56–61. http://dx.doi.org/10.17221/55/2009-hortsci.

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Isoenzyme polymorphism was studied in 20 almond (Prunus dulcis [Mill.] D.A. Webb) genotypes selected from seedling populations of unknown almond cultivars in the region of northern Serbia (Vojvodina). Fourteen enzyme systems were studied using the method of vertical polyacrylamide gel electrophoresis. Ten systems were polymorphic in twelve loci. This polymorphism allowed unique identification of all studied genotypes. The most useful enzyme for analysis of almond genetic variability was menadione reductase. Polymorphism identified for alkaline phosphatase, formate dehydrogenase, glutamate dehydrogenase, malic enzyme, and menadione reductase was reported for the first time in almond. Cluster analysis was used to construct a dendrogram on which five clusters with different number of genotypes could be identified.

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Kafkas, Salih, Yıldız Doğan, Ali Sabır, Ali Turan, and Hasbi Seker. "Genetic Characterization of Hazelnut (Corylus avellana L.) Cultivars from Turkey Using Molecular Markers." HortScience 44, no. 6 (October 2009): 1557–61. http://dx.doi.org/10.21273/hortsci.44.6.1557.

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Genetic relationships among 18 Turkish hazelnut (Corylus avellana L.) cultivars were investigated using randomly amplified polymorphic DNA (RAPD), intersimple sequence repeat (ISSR), and amplified fragment length polymorphism (AFLP) markers. Twenty-five RAPD primers, 25 ISSR primers, and eight AFLP primer pairs generated a total of 434 polymorphic marker loci. The three marker systems were able to differentiate the cultivars. Genetic similarity index values ranged from a high of 0.96 for ‘Kan’ and ‘UzunMusa’ to a low of 0.73 for ‘Yassi Badem’ and ‘Kalinkara’. The genetic relationships were presented as an unweighted pair group method with arithmetic average (UPGMA) dendrogram and a three-dimensional principal coordinate analysis (PCoA) plot. The UPGMA dendrogram showed two main clusters, while PCoA analysis showed three groups. Cultivar-specific markers were produced by all marker systems for 10 cultivars. This study demonstrates the usefulness of molecular markers for identification of hazelnut cultivars.

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O'Leary, Maureen C., and Thomas H. Boyle. "Isozyme Polymorphism and Inheritance in Rhipsalidopsis and Schlumbergera (Cactaceae)." HortScience 30, no. 4 (July 1995): 856G—857. http://dx.doi.org/10.21273/hortsci.30.4.856g.

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Cultivars and seedlings of Rhipsalidopsis and Schlumbergera were subjected to isozyme analysis using seven enzyme systems [aspartate aminotransferase (AAT), aminopeptidase (AMP), glucose-6-phosphate isomerase (GPI), malate dehydrogenase (MDH), phosphoglucomutase (PGM), shikimate dehydrogenase (SKD), and triose phosphate isomerase (TPI)]. Isozymes were extracted from phylloclades and roots, and were separated by polyacrylamide gel electrophoresis (PAGE) using single percentage (5% to 10%) gels. Six enzymes exhibited polymorphism in Rhipsalidopsis, whereas all seven enzymes were polymorphic in Schlumbergera. Inheritance studies were performed on AAT, GPI, MDH, PGM, and TPI for Rhipsalidopsis and on AMP, PGM, and SKD for Schlumbergera. Significant segregation distortion was observed in some families. Polymorphic isozymes are potentially useful markers for cultivar identification and for genetic and breeding studies.

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Makudera, A. O., and S. M. Lakiza. "Interaction in the systems Y2O3−Ln2O3 (Ln=Tb–Lu)." Uspihi materialoznavstva 2021, no. 2 (June 1, 2021): 72–78. http://dx.doi.org/10.15407/materials2021.02.072.

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Based on the analysis of literature data from experimentally constructed phase diagrams of Y2O3 − Ln2O3 systems (Ln = Tb − Lu), as well as temperatures of polymorphic transformations of rare earth oxides (REE), tentative phase diagrams of Y2O3 − Ln2O3 systems (Ln = Tb − Lu) were constructed in wide intervals of temperatures and concentrations. Prediction of the binary phase diagrams structure of yttria − yttrium subgroup lanthanides systems was carried out on the basis of three principles: 1. Since double systems are formed by lanthanide oxides of one (yttrium) subgroup, it is very likely that in such systems continuous solid solutions will be formed between the components. 2. Intermediate binary phases are not formed in these systems. 3. The formation of continuous solid solutions occurs with a decrease in the temperatures of phase transformations in the solid state to a minimum shifted towards a lower transformation temperature of the system component. The forecast of the Y2O3 – Ln2O3 systems phase diagrams structure, where Ln = Tb – Lu, indicates the complete solubility of the components in the liquid and solid states. Binary compounds in the considered systems are not predicted. Phase transformations in the solid solutions on the basis of polymorphic modifications X, H, A, B and C of lanthanide oxides cascade at high temperatures by the peritectoid mechanism. Below 1850 °C regions of solid solutions with cubic C-structure of REE oxides are formed in the whole range of concentrations in the systems. Key words: REE oxides, yttria, polymorphs of REE oxides, phase diagram.

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Colic, Slavica, Vera Rakonjac, Milica Fotiric-Aksic, Dragan Nikolic, Vladislav Ognjanov, and Dragan Rahovic. "Dehydrogenase isoenzyme polymorphism in genus Prunus, subgenus Cerasus." Genetika 44, no. 3 (2012): 619–32. http://dx.doi.org/10.2298/gensr1203619c.

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Dehydrogenase polymorphism was studied in 36 sour cherry (Prunus cerasus L.), sweet cherry (Prunus avuim L.), mahaleb (Prunus mahaleb L.), ground cherry (Prunus fruticosa Pall.), duke cherry (Prunus gondounii Redh.), Japanese flowering cherry (Prunus serrulata Lindl.) and four iterspecific hybrids (standard cherry rootstocks ?Gisela 5?, ?Gisela 6?, ?Max Ma? and ?Colt?). Inner bark of one-year-old shoots, in dormant stage, was used for enzyme extraction. Vertical PAGE was used for isoenzyme analysis: alcohol dehydrogenase (ADH), formate dehydrogenase (FDH), glutamate dehydrogenase (GDH), isocitrate dehydrogenaze (IDH), malate dehydrogenase (MDH), phosphogluconate dehydrogenase (PGD), and shikimate dehydrogenase (SDH). All studied systems were polymorphic at 10 loci: Adh -1 (3 genotypes) and Adh-2 (5 genotypes), Fdh-1 (2 genotypes), Gdh-1 (3 genotypes), Idh-1 (4 genotypes) i Idh -2 (5 genotypes), Mdh-1 (3 genotypes), Pgd-1 (4 genotypes), Sdh-1 (1 genotype) i Sdh-2 (3 genotypes). Cluster analysis was used to construct dendrogram on which four groups of similar genotypes were separated. Obtained results indicate that studied enzyme systems can be used for determination of genus Prunus, subgenus Cerasus. Among studied enzyme systems ADH, IDH and SDH were the most polymorphic and most useful to identify genetic variability. Polymorphism of FDH and GDH in genus Prunus, subgenus Cerasus was described first time in this work. First results for dehydrogenase variability of Oblacinska indicate that polymorphism of loci Idh-2 and Sdh-2 can be useful for discrimination of different clones.

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Bueno, Maria S., Marcela R. Longhi, and Claudia Garnero. "Pharmaceutical Systems as a Strategy to Enhance the Stability of Oxytetracycline Hydrochloride Polymorphs in Solution." Pharmaceutics 15, no. 1 (January 5, 2023): 192. http://dx.doi.org/10.3390/pharmaceutics15010192.

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In order to improve the stability of oxytetracycline hydrochloride, a polymorphic antibiotic set of novel binary systems were developed using β-cyclodextrin and amino acids with different acid-basic characteristics as ligands. The formation constants for each system containing β-cyclodextrin, L-aspartic acid, histidine and N-acetylcysteine were determined by Scott’s method and statistical studies. The structure of the binary systems with β-cyclodextrin and N-acetylcysteine was elucidated by NMR experiments. The effect β-cyclodextrin and N-acetylcysteine on the polymorph’s chemical stability in aqueous and phosphate buffered saline solutions at 25 °C was monitored by an optimized and validated high-performance liquid chromatography method. The combination of N-acetylcysteine with the three polymorphs and the β-cyclodextrin system obtained with the form III demonstrated a reduction in the degradation rate of oxytetracycline hydrochloride in the aqueous solution when compared to each free form, with an increase of 20 h in the half time. It evidences that the use of amino acids as ligands constitutes an interesting alternative for pharmaceutical areas. In conclusion, based on the results obtained, these pharmaceutical systems could be candidates for the development of a pharmaceutical formulation for the administration of the drug through reconstituted solutions using the binary system as a promising tool for improving the stability of oxytetracycline hydrochloride polymorphs in solution.

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Tian, F., H. Qu, M. Louhi-Kultanen, and J. Rantanen. "Insight into Crystallization Mechanisms of Polymorphic Hydrate Systems." Chemical Engineering & Technology 33, no. 5 (April 28, 2010): 833–38. http://dx.doi.org/10.1002/ceat.200900572.

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27

Gimelfarb, A. "Pleiotropy and multilocus polymorphisms." Genetics 130, no. 1 (January 1, 1992): 223–27. http://dx.doi.org/10.1093/genetics/130.1.223.

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Abstract It is demonstrated that systems of two pleiotropically related characters controlled by additive diallelic loci can maintain under Gaussian stabilizing selection a stable polymorphism in more than two loci. It is also shown that such systems may have multiple stable polymorphic equilibria. Stabilizing selection generates negative linkage disequilibrium, as a result of which the equilibrium phenotypic variances are quite low, even though the level of allelic polymorphisms can be very high. Consequently, large amounts of additive genetic variation can be hidden in populations at equilibrium under stabilizing selection on pleiotropically related characters.

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Luo, W., Z. Zhang, and X. Wang. "Designing polymorphic circuits with polymorphic gates: a general design approach." IET Circuits, Devices & Systems 1, no. 6 (2007): 470. http://dx.doi.org/10.1049/iet-cds:20070057.

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Begum, Kazi Nahida, and Sheikh Shamimul Alam. "Genetic diversity in nine chickpea (Cicer arietinum L.) varieties based on different molecular markers." Bangladesh Journal of Botany 48, no. 1 (March 31, 2019): 195–203. http://dx.doi.org/10.3329/bjb.v48i1.47491.

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Nine varieties (BARI Chola-1 to BC-9) of chickpea (Cicer arietinum L.) were studied with respect to isozymes, SDS-PAGE, amplified DNA produced by RAPD- and SSR-markers. The varieties could be characterized by SDS-PAGE bands on the basis of their location, size and intensity. Three isozyme systems, namely acid phosphatase, esterase and peroxidase were investigated of which esterase was found to be suitable for produced distinct polymorphic bands with 57.14% diversity. Ten RAPD primers were producing 74 bands with 93.24% polymorphisms which indicated highly diverse nature. In addition to polymorphism, 12 variety-specific RAPD fragments were identified. Ten SSR primer pairs were producing 20 distinct bands of which 11 were considered as polymorphic (55%). On the basis of RAPD and SSR analysis, BC-1 and BC- 6 were placed in cluster-1 and the remaining varieties were placed in cluster-2. On the other hand, the combined data of three isozymes systems and SDS-PAGE made BC-8 and BC-9 were different and thus placed in cluster-2 while the other seven varieties were placed in cluster-1.

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Viñes, Francesc, Oriol Lamiel-Garcia, Francesc Illas, and Stefan T. Bromley. "Size dependent structural and polymorphic transitions in ZnO: from nanocluster to bulk." Nanoscale 9, no. 28 (2017): 10067–74. http://dx.doi.org/10.1039/c7nr02818k.

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We report on an extensive computational modelling survey of (ZnO)_N nanostructures ranging from bottom-up generated nanoclusters to top-down nanoparticles cuts from various bulk polymorphs. The obtained results enable us to follow the energetic preferences of structure and polymorphism in (ZnO)_N systems with increasing N up to the bulk.

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31

Calligaris, Guilherme, Ana Paula Ribeiro, Adenilson dos Santos, and Lisandro Cardoso. "Rietveld Method Applied for Triacylglycerol Polymorphism Analysis." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1764. http://dx.doi.org/10.1107/s2053273314082357.

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The characterization of the fat components becomes very useful in the formulation of shortening, margarines and fatty products due to their unique properties of plasticity, texture, solubility and aeration. The qualitative analysis obtained by X-ray diffraction (XRD) can be further improved in order to fulfill the lack of information on the triacylglycerol (TAG) in the hardfat systems aiming a complete polymorph characterization. In this work, as an attempt to quantify the distinct β and β' TAG polymorphs, XRD was combined with Rietveld refinement method and applied to two types of samples: mixtures (M) and blended hardfats (B) samples involving fully hydrogenated of soybean (FHSO) and palm (FHPO) oils. M-samples were prepared with linear concentrations of FHSO (β) and FHPO (β') and their Rietveld analysis have provided the expected content trend through the involved polymorphic phases with a very good agreement (~5%). This result validates the Rietveld method applicability on this kind of materials. The Rietveld method applied for B-samples has shown that β' polymorphic form prevails over the β-form, even for samples originally prepared with FHSO (β)/FHPO (β') = 60/40 ratio (see figure). This result indicates the influence of the seeding process (earlier crystallization of β' phase). This first quantitative approach for blended samples represents a very useful contribution towards the full characterization of fats.

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Abadi, M., L. Cardelli, B. Pierce, and D. Rémy. "Dynamic typing in polymorphic languages." Journal of Functional Programming 5, no. 1 (January 1995): 111–30. http://dx.doi.org/10.1017/s095679680000126x.

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AbstractThere are situations in programming where some dynamic typing is needed, even in the presence of advanced static type systems. We investigate the interplay of dynamic types with other advanced type constructions, discussing their integration into languages with explicit polymorphism (in the style of system F), implicit polymorphism (in the style of ML), abstract data types, and subtyping.

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Gabdulkhaev, Mukhammet N., Marat A. Ziganshin, Aleksey V. Buzyurov, Christoph Schick, Svetlana E. Solovieva, Elena V. Popova, Aidar T. Gubaidullin, and Valery V. Gorbatchuk. "Smart control of calixarene polymorphic states." CrystEngComm 22, no. 42 (2020): 7002–15. http://dx.doi.org/10.1039/d0ce01070g.

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34

Sridhar, Balasubramanian, Jagadeesh Babu Nanubolu, and Krishnan Ravikumar. "The first polymorph in the family of nucleobases: a second form of cytosine." Acta Crystallographica Section C Structural Chemistry 71, no. 2 (January 24, 2015): 128–35. http://dx.doi.org/10.1107/s2053229615000492.

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A new polymorph of cytosine, C4H5N3O, is reported half a century after the report of its first known crystal structure [Barker & Marsh (1964).Acta Cryst.17, 1581–1587]. Cytosine thus provides the first polymorphic example in the category of parent nucleobases. The new form, denoted (Ib), was observed unexpectedly during an attempt to cocrystallize cytosine with catechol. Form (Ib) crystallizes in the orthorhombic centrosymmetric space groupPccnwith two molecules in the asymmetric unit. The previously known form, denoted (Ia), crystallizes in the orthorhombic noncentrosymmetric space groupP212121. The cytosine molecule is planar in both forms. Hydrogen-bonding interactions are also similar for both forms. Infinite one-dimensional ribbons composed of cytosine base-pair dimers inR22(8) arrangements are observed in both (Ia) and (Ib). However, the way that the ribbons are packed differs in (Ia) and (Ib). This appears to guide the centrosymmetricversusnoncentrosymmetric space-group selection through the formation of an inversion-related motif in polymorph (Ib) and a helical propagation in polymorph (Ia). A few selected polymorphic systems have been gathered from the Cambridge Structural Database to understand possible structural features responsible for achiral molecules adopting centro- and noncentrosymmetric space groups.

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Hoser, Anna A., Łukasz Dobrzycki, Matthias J. Guttman, and Krzysztof Woźniak. "Experimental and theoretical charge densities in two polymorphic systems." Acta Crystallographica Section A Foundations of Crystallography 66, a1 (August 29, 2010): s94. http://dx.doi.org/10.1107/s0108767310097989.

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36

Munroe, Áine, Denise Croker, B. Kieran Hodnett, and Colin C. Seaton. "Epitaxial growth of polymorphic systems: The case of sulfathiazole." CrystEngComm 13, no. 19 (2011): 5903. http://dx.doi.org/10.1039/c1ce05585b.

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37

Geiger, Philipp, and Christoph Dellago. "Neural networks for local structure detection in polymorphic systems." Journal of Chemical Physics 139, no. 16 (October 28, 2013): 164105. http://dx.doi.org/10.1063/1.4825111.

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38

Blagden, N., R. J. Davey, H. F. Lieberman, L. Williams, R. Payne, R. Roberts, R. Rowe, and R. Docherty. "Crystal chemistry and solvent effects in polymorphic systems Sulfathiazole." Journal of the Chemical Society, Faraday Transactions 94, no. 8 (1998): 1035–44. http://dx.doi.org/10.1039/a706669d.

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Barrett, Spencer C. H., and Lawrence D. Harder. "The evolution of polymorphic sexual systems in daffodils (Narcissus)." New Phytologist 165, no. 1 (September 2, 2004): 45–53. http://dx.doi.org/10.1111/j.1469-8137.2004.01183.x.

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40

Adawiyah, Noorul, Muhammad Moniruzzaman, Siti Hawatulaila, and Masahiro Goto. "Ionic liquids as a potential tool for drug delivery systems." MedChemComm 7, no. 10 (2016): 1881–97. http://dx.doi.org/10.1039/c6md00358c.

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The pharmaceutical industries face a series of challenges in the delivery of many newly developed drug molecules because of their low solubility, bioavailability, stability and polymorphic conversion.

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41

Li, Minhuan, Yanshuang Chen, Hajime Tanaka, and Peng Tan. "Revealing roles of competing local structural orderings in crystallization of polymorphic systems." Science Advances 6, no. 27 (July 2020): eaaw8938. http://dx.doi.org/10.1126/sciadv.aaw8938.

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Most systems have more than two stable crystalline states in the phase diagram, which is known as polymorphism. Crystallization in such a system is often under strong influence of competing orderings linked to those crystals. However, how such competition affects crystal nucleation and ordering toward the final crystalline state is largely unknown. This is primarily because the competition takes place locally and thus is masked by large positional fluctuations. We develop a unique method to correctly identify local symmetries by removing their distortions due to positional fluctuations. This allows us to experimentally access the spatiotemporal fluctuations of local symmetries at a single-particle level in crystallization of a charged colloidal system near the body-centered cubic–face-centered cubic border. Thus, we successfully reveal the crucial roles of competing ordering in the initial selection of polymorphs and the final grain boundary motion toward the most stable state from a microscopic perspective.

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42

Greiner, John. "Weak polymorphism can be sound." Journal of Functional Programming 6, no. 1 (January 1996): 111–41. http://dx.doi.org/10.1017/s0956796800001593.

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AbstractThe weak polymorphic type system of Standard ML of New Jersey (SML/NJ) (MacQueen, 1992) has only been presented as part of the implementation of the SML/NJ compiler, not as a formal type system. As a result, it is not well understood. And while numerous versions of the implementation have been shown unsound, the concept has not been proved sound or unsound. We present an explanation of weak polymorphism and show that a formalization of this is sound. We also relate this to the SML/NJ implementation of weak polymorphism through a series of type systems that incorporate elements of the SML/NJ type inference algorithm.

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Tivang, J. G., J. Nienhuis, O. S. Smith, and J. S. C. Smith. "Comparison of Five Molecular Marker Systems in Assessing Genetic Relationships among 39 Elite Corn Belt Inbreds." HortScience 30, no. 4 (July 1995): 772C—772. http://dx.doi.org/10.21273/hortsci.30.4.772c.

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The statistical properties associated with molecular markers are important when used to characterize germplasm. Evaluation of these properties are necessary for informed selection of one marker system over another. Five different molecular marker systems, Amplified Fragment Length Polymorphism (AFLPs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Random Amplified Polymorphic DNA (RAPDs), Restriction Fragment Length Polymorphism (RFLPs), and Isozymes were used to evaluate 39 elite corn belt inbreds. Each system was characterized for fragment frequency distribution, and band correlation distribution as a measure of independence. A regression model estimating resolution and rate of information addition was constructed using the sampling variance. All marker systems were evaluated according to this model. The model facilitated genetic relationships among the inbreds to be compared at equivalent performance level among all marker systems. Four performance levels resulted in 10 comparisons. Pairwise test of significance were conducted using t tests where the null-distributions were obtained by the bootstrap procedure. The maker system were ranked, assisting breeders in selecting marker systems for germplasm organization.

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44

Lin, Tsan-Piao, Tzen-Yu Lee, Li-Feng Yang, Yong-Ly Chung, and Jenq-Chuan Yang. "Comparison of the allozyme diversity in several populations of Chamaecyparisformosensis and Chamaecyparistaiwanensis." Canadian Journal of Forest Research 24, no. 10 (October 1, 1994): 2128–34. http://dx.doi.org/10.1139/x94-273.

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Genetic diversity within and genetic differentiation among three populations of Chamaecyparisformosensis Matsum. and two populations of Chamaecyparistaiwanensis Masam. & Suzuki were investigated using one-year-old seedlings collected from central and northern Taiwan. For C. formosensis 330 seedlings from 33 seed trees were used, while for C. taiwanensis 260 seedlings from 26 seed trees were used. Eleven enzyme systems were investigated. In C. formosensis, 5 of the 21 loci examined were polymorphic. The average percentage of polymorphic loci per population was 20.6% at the 99% criterion for polymorphism. Mean expected heterozygosity ranged from 0.079 to 0.100 in the different populations. On average, there were 6.6 to 9.2% heterozygous loci per individual and 1.24 to 1.29 alleles per locus; the effective number of alleles per locus ranged from 1.09 to 1.11. In C. taiwanensis, 7 of the 20 loci examined were polymorphic and the average percentage of polymorphic loci per population was 22.5%. Mean expected heterozygosity ranged from 0.044 to 0.060. On average there were 4.5 to 5.6% heterozygous loci per individual and 1.45 alleles per locus; the effective number of alleles per locus ranged from 1.05 to 1.08. The surprisingly low expected heterozygosity and percentage of polymorphic loci compared with other conifer probably reflects the insular nature of these species. Partitioning the genetic variability into within- and among-population components with F-statistics led to an estimate of within-population variation of 95% of the total variation in both C. formosensis and C. taiwanensis. Chamaecyparisformosensis had a positive fixation index (0.109) that was significantly different from zero at the 5% level, indicating that most loci have slightly higher frequencies of homozygotes. Chamaecyparistaiwanensis, however, had a fixation index close to zero (0.036), which suggests that most loci are in Hardy–Weinberg equilibrium. The genetic distance between C. formosensis and C. taiwanensis was 0.70, which clearly separates these two species.

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Hisaki, Ichiro, Norimitsu Tohnai, and Mikiji Miyata. "Affirmative polymorph generation of annulenes by using CH/O interactions." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C543. http://dx.doi.org/10.1107/s205327331409456x.

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CH/O interaction is recognized as a weak hydrogen bond with less directionality, compared with a strong hydrogen bond such as that between carboxylic acids. Therefore, the interaction does not seem to be suitable for precise design of crystal structures. In connection with this, however, we emphasized that the CH/O interaction, particularly that provided by methyl ester group, can utilize for affirmative generation of polymorphs of cyclic pi conjugated molecules. Since functionality of solid state materials based on pi conjugated molecules is crucially affected by their molecular arrangements, polymorphs are exactly appropriate systems to reveal the superstructure-dependent properties of such the materials, and therefore, affirmative preparation of polymorphs of pi conjugated molecules is challenging. Herein, we describe formation, crystallographic characterization, and superstructure-dependent properties of polymorphs of methyl ester functionalized dehydrobenzoannulenes (DBAs), a family of cyclic conjugated molecules consisted of benzene rings and acetylene units. We synthesized five DBA derivatives 1-5 with two types of annulene cores (octadehydrodibenzo[12]annulene and octadehydrotribenzo[14]annulene cores) and different number and position of methyl ester groups (Scheme1). These derivatives exhibit two to five polymorphic crystals with physical properties strongly depending with their supramolecular structures.[1-3] We believe that the present polymorph generation is exactly provided by rotationally flexible conformations of the ester groups and versatile ways of directionally tolerant CH/O interactions of the ester groups.

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FLUET, MATTHEW, and RICCARDO PUCELLA. "Phantom types and subtyping." Journal of Functional Programming 16, no. 6 (June 9, 2006): 751–91. http://dx.doi.org/10.1017/s0956796806006046.

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We investigate a technique from the literature, called the phantom-types technique, that uses parametric polymorphism, type constraints, and unification of polymorphic types to model a subtyping hierarchy. Hindley-Milner type systems, such as the one found in Standard ML, can be used to enforce the subtyping relation, at least for first-order values. We show that this technique can be used to encode any finite subtyping hierarchy (including hierarchies arising from multiple interface inheritance). We formally demonstrate the suitability of the phantom-types technique for capturing first-order subtyping by exhibiting a type-preserving translation from a simple calculus with bounded polymorphism to a calculus embodying the type system of SML.

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Lim, Seung-Ho, Hyunchul Seok, and Ki-Woong Park. "Polymorphic Memory: A Hybrid Approach for Utilizing On-Chip Memory in Manycore Systems." Electronics 9, no. 12 (December 3, 2020): 2061. http://dx.doi.org/10.3390/electronics9122061.

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The key challenges of manycore systems are the large amount of memory and high bandwidth required to run many applications. Three-dimesnional integrated on-chip memory is a promising candidate for addressing these challenges. The advent of on-chip memory has provided new opportunities to rethink traditional memory hierarchies and their management. In this study, we propose a polymorphic memory as a hybrid approach when using on-chip memory. In contrast to previous studies, we use the on-chip memory as both a main memory (called M1 memory) and a Dynamic Random Access Memory (DRAM) cache (called M2 cache). The main memory consists of M1 memory and a conventional DRAM memory called M2 memory. To achieve high performance when running many applications on this memory architecture, we propose management techniques for the main memory with M1 and M2 memories and for polymorphic memory with dynamic memory allocations for many applications in a manycore system. The first technique is to move frequently accessed pages to M1 memory via hardware monitoring in a memory controller. The second is M1 memory partitioning to mitigate contention problems among many processes. Finally, we propose a method to use M2 cache between a conventional last-level cache and M2 memory, and we determine the best cache size for improving the performance with polymorphic memory. The proposed schemes are evaluated with the SPEC CPU2006 benchmark, and the experimental results show that the proposed approaches can improve the performance under various workloads of the benchmark. The performance evaluation confirms that the average performance improvement of polymorphic memory is 21.7%, with 0.026 standard deviation for the normalized results, compared to the previous method of using on-chip memory as a last-level cache.

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Pita, Alfonso, María Fernández-Míguez, and Pablo Presa. "EST-Microsatellite Types and Structural Scenarios in European Hake Fisheries." Animals 12, no. 11 (June 4, 2022): 1462. http://dx.doi.org/10.3390/ani12111462.

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A fishery’s structure and connectivity are priors to its effective management. A successful description of such processes depends on both the sampling design and the choice of adequate genetic markers. EST markers are perfusing the studies of marine metapopulations and are believed to provide access to functional polymorphisms. However, the assumed adaptive role of outlier EST loci might not be generalizable. EST-microsatellites represent the upper polymorphic boundary in these regions because of their high mutation rate. We have subclassified the polymorphisms of EST-microsatellites to assess their structural contribution in the European hake, a paradigmatic and highly mobile marine species (HMMS). Because of the counterbalanced forces between directional markers (15%) and balanced markers (23%), the whole marker set offers the same structural situation as the one observed with neutral markers (62%), i.e., k = 2 gene pools. In contrast to outlier EST- microsatellites, neutral EST subsets allow one to measure crucial population phenomena for fisheries’ management. The high inter-population divergence of outlier EST-microsatellites is compatible with drifted post-selection genomic regions rather than with ongoing local selective pressures. The structural scenario in hake is explainable by a limited gene flow across the Almería-Oran Front (AOF) and by the within-basin IBD pattern of connectivity plus drift-related demographic events. This study highlights how polymorphic properties of EST-microsatellite types can be useful to address mutually excluding research tasks in fisheries, i.e., to address its evolutionary history (directional markers or FAPS: Fossil Adaptive Polymorphic Systems); to delineate management units (neutral markers or NAPS: Non Adaptive Polymorphic Systems); or to ensure sustainability (balanced markers or APS: Adaptive Polymorphic Systems).

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Lazić, Ranko, Tom Newcomb, and Bill Roscoe. "Polymorphic Systems with Arrays, 2-Counter Machines and Multiset Rewriting." Electronic Notes in Theoretical Computer Science 138, no. 3 (December 2005): 61–86. http://dx.doi.org/10.1016/j.entcs.2005.02.064.

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Jouannaud, Jean-Pierre, and Albert Rubio. "Polymorphic higher-order recursive path orderings." Journal of the ACM 54, no. 1 (March 2007): 1–48. http://dx.doi.org/10.1145/1206035.1206037.

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Journal articles on the topic 'Polymorphic systems'

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