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Journal articles on the topic 'Systematics'

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Author: Grafiati

Published: 4 June 2021

Last updated: 13 April 2024

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1

Andersen, Nils Møller. "Phylogeny and classification of aquatic bugs (Heteroptera, Nepomorpha). An essay review of Mahner's 'Systema Cryptoceratum Phylogeneticum'." Insect Systematics & Evolution 26, no. 2 (1995): 159–66. http://dx.doi.org/10.1163/187631295x00161.

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AbstractThis essay is essentially a review of the monographic work by the German zoologist Martin Mahner : 'Systema Cryptoceratum Phylogeneticum (Insecta, Heteroptera)' (Zoologica, Heft 143, Stuttgart 1993). The monograph is the most comprehensive systematic account of the aquatic bugs to date and the first major work on this group where the principles of phylogenetic (cladistic) systematics are consistently applied. Mahner follows the principles of the 'konsequentphylogenetische oder cladistischen Systematik', being Willi Hennig's phylogenetic systematics as interpreted and modified by Peter Ax. The methodological procedures recommended by this school of systematics is controversial, however, and call for a broader discussion of current trends in systematics as exemplified by the phylogeny and classification of the aquatic bugs.

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2

Carlson, Sandra J. "Ghosts of the past, present, and future in brachiopod systematics." Journal of Paleontology 75, no. 6 (November 2001): 1109–18. http://dx.doi.org/10.1017/s0022336000017169.

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Three historical phases can be distinguished in the study of brachiopod systematics over the past 75 years. Prior to 1956, systematic neontologists and paleontologists struggled to reconcile differences in perceived evolutionary patterns (and thus classifications) based largely on static morphological differences observed separately among living brachiopods and among fossil brachiopods. Following 1956, patterns of morphological distribution began to be interpreted relative to the processes by which they were formed, and a more dynamic view of brachiopod phylogeny and classification resulted. Over the past decade, newer methodologies (phylogenetic systematics) have allowed older phylogenetic hypotheses to be tested and evaluated. The major challenges that brachiopod systematists now face are not unique to brachiopods; they concern improving the methods of phylogeny (and classification) reconstruction so that all the sources of data available to paleontologists can be utilized more effectively. In the future, I predict that more intensified, global fossil collecting, together with further investigation of the embryology and development of brachiopods, and molecular systematic research, will play an increasingly larger role in revising the classification currently in use.

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3

Danks, H. V., and George E. Ball. "SYSTEMATICS AND ENTOMOLOGY: SOME MAJOR THEMES." Memoirs of the Entomological Society of Canada 125, S165 (1993): 257–72. http://dx.doi.org/10.4039/entm125165257-1.

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AbstractSystematics allows the extraordinary diversity of biological systems to be understood, and information about organisms to be organized and made accessible. Key patterns that help to interpret natural processes can be summarized, and biological traits predicted, by determining the relationships of natural taxa. Ecological roles are made visible and existing knowledge is made accessible only through specific names. Most organismic diversity is represented by terrestrial arthropods, but knowledge is very incomplete. Even for species found in Canada, half have not been described and the immature stages of most are unknown.Systematics supports entomology and underpins studies of biology in many different ways. From these roles, understanding is gained about diversity and evolution, distributions and biogeographically significant regions of the country, adaptations as related especially to species interactions and metamorphosis, and the application of systematics information. In addition, the values of basic systematic work, modern techniques, and long-term coordinated efforts in studying the fauna are emphasized.A coordinated study of diversity by systematists in conjunction with ecologists and others is required. Such a coordinated approach is timely given recent recognition that the world depends on self-sustaining but increasingly threatened biological systems. Diverse organisms maintain those systems but can be distinguished only through systematics. Adequate long-term support — for systematics positions, research collections, activities that include the preparation of basic works such as monographs, and educational facilities — is required to underpin the systematics component of such a coordinated study.

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4

Funk, V. A., and D. Cannatella. "The Society of Systematic Biologists' Awards in Systematics." Systematic Biology 48, no. 4 (October 1, 1999): 832–37. http://dx.doi.org/10.1080/106351599260058.

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5

Chernikova, N. Yu. "ON SYSTEMATICS OF CRYSTAL STRUCTURES." Tambov University Reports. Series: Natural and Technical Sciences 22, no. 5-1 (2017): 1073–76. http://dx.doi.org/10.20310/1810-0198-2017-22-5-1073-1076.

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6

van Viersen, Allart P. "Systematics of Devonian trochurine trilobites (Lichidae)." Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 300, no. 2 (May 28, 2021): 175–87. http://dx.doi.org/10.1127/njgpa/2021/0983.

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7

Daly, Douglas C. "Systematics and systematists at The New York Botanical Garden." Brittonia 68, no. 3 (April 12, 2016): 230–37. http://dx.doi.org/10.1007/s12228-016-9415-7.

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8

Carlson, Sandra J. "Evolution and Systematics." Paleontological Society Special Publications 11 (2002): 77–96. http://dx.doi.org/10.1017/s2475262200009837.

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The biological process of evolution—descent with modification—generates and structures the remarkable diversity of life on Earth today and in the geological past. Take a moment to consider the vast number of different kinds of living things: mushrooms, koalas, sunflowers, whales, mosquitoes, kelp, bacteria, tapeworms, lichens, clams, redwoods,…the list could go on and on, seemingly forever. Without some understanding of how the diversity of life was generated, the scope of the diversity may seem overwhelming, perhaps even unknowable. Fortunately the structure of this extraordinary diversity, generated by the process of evolution, can be discovered using the methods of systematics. Evolution can be thought of as “an axiom from which systematic methods and concepts are deduced” (de Queiroz, 1988). Systematics, therefore, provides a way to organize the diversity surrounding us, and make sense of it in an evolutionary framework. Patterns of similarity and difference in morphology, genetics, and development—the evidence of evolution—can only be explained in an evolutionary context by means of systematics. No other method seeks to identify patterns that are evolutionary in origin, generated by the process of common descent.

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9

Carlson, Sandra J. "Evolution and Systematics." Paleontological Society Special Publications 9 (1999): 95–118. http://dx.doi.org/10.1017/s2475262200014039.

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The biological process of evolution – descent with modification – generates and structures the remarkable diversity of life on Earth today and in the geological past. Take a moment to consider the vast number of different kinds of living things: mushrooms, koalas, sunflowers, whales, mosquitoes, kelp, bacteria, tapeworms, lichens, clams, redwoods,…. the list could go on and on, seemingly forever. Without some understanding of how the diversity of life was generated, the scope of the diversity may seem overwhelming, perhaps even unknowable. Fortunately the structure of this extraordinary diversity, generated by the process of evolution, can be discovered using the methods of systematics. Evolution can be thought of as “an axiom from which systematic methods and concepts are deduced” (de Queiroz, 1988). Systematics, therefore, provides a way to organize the diversity surrounding us, and make sense of it in an evolutionary framework. Patterns of similarity and difference in morphology, genetics, and development — the evidence of evolution — can only be explained in an evolutionary context by means of systematics. No other method seeks to identify patterns that are evolutionary in origin, generated by the process of common descent.

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10

Bischler, Helene, and Marie-Catherine Boisselier-Dubayle. "New approaches to the systematics of liverworts." Nova Hedwigia 70, no. 1-2 (February 1, 2000): 37–44. http://dx.doi.org/10.1127/nova.hedwigia/70/2000/37.

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11

Taaki, Jamila S., Athol J. Kemball, and Farzad Kamalabadi. "Robust Detrending of Spatially Correlated Systematics in Kepler Light Curves Using Low-rank Methods." Astronomical Journal 167, no. 2 (January 15, 2024): 60. http://dx.doi.org/10.3847/1538-3881/ad1110.

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Abstract Light curves produced by wide-field exoplanet transit surveys such as CoRoT, Kepler, and the Transiting Exoplanet Survey Satellite are affected by sensor-wide systematic noise, which is correlated both spatiotemporally and with other instrumental parameters such as the photometric magnitude. Robust and effective systematics mitigation is necessary to achieve the level of photometric accuracy required to detect exoplanet transits and to faithfully recover other forms of intrinsic astrophysical variability. We demonstrate the feasibility of a new exploratory algorithm to remove spatially correlated systematic noise and detrend light curves obtained from wide-field transit surveys. This spatial systematics algorithm is data-driven and fits a low-rank linear model for the systematics conditioned on a total-variation spatial constraint. The total-variation constraint models spatial systematic structure across the sensor on a foundational level. The fit is performed using gradient descent applied to, a variable reduced least-squares penalty and a modified form of total-variation prior; both the systematics basis vectors and their weighting coefficients are iteratively varied. The algorithm was numerically evaluated against a reference principal component analysis, using both signal injection on a selected Kepler dataset, as well as full simulations within the same Kepler coordinate framework. We develop our algorithm to reduce the overfitting of astrophysical variability over longer signal timescales (days) while performing comparably relative to the reference method for exoplanet transit timescales. The algorithm performance and application are assessed, and future development is outlined.

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12

Sell, Roger D., and Helmut Bonheim. "Literary Systematics." Modern Language Review 87, no. 4 (October 1992): 909. http://dx.doi.org/10.2307/3731428.

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13

Greller, Andrew M., Samuel B. Jones, and Arlene E. Luchsinger. "Plant Systematics." Bulletin of the Torrey Botanical Club 114, no. 2 (April 1987): 199. http://dx.doi.org/10.2307/2996134.

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14

Olmstead, Richard G., David M. Hillis, Craig Moritz, and Barbara K. Mable. "Molecular Systematics." Systematic Biology 45, no. 4 (December 1996): 607. http://dx.doi.org/10.2307/2413537.

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15

Mayo, Simon, and Gurchuran Singh. "Plant Systematics." Kew Bulletin 56, no. 3 (2001): 648. http://dx.doi.org/10.2307/4117689.

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16

Kim, K. C. "Reviving Systematics." BioScience 37, no. 3 (March 1987): 174–75. http://dx.doi.org/10.2307/1310513.

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17

Editor, Associate. "Plant Systematics." Indian Journal of Forestry 43, no. 3 (August 1, 2021): 293–94. http://dx.doi.org/10.54207/bsmps1000-2021-s6m5sl.

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18

Moore, Debra S., David M. Hillis, Craig Moritz, and Barbara K. Mable. "Molecular Systematics." Copeia 1996, no. 4 (December 27, 1996): 1058. http://dx.doi.org/10.2307/1447682.

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19

Rushing, Ann E., and Norton G. Miller. "Bryophyte Systematics." Bryologist 97, no. 4 (1994): 465. http://dx.doi.org/10.2307/3243922.

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20

Waterman, P. G., and A. I. Gray. "Chemical systematics." Natural Product Reports 4 (1987): 175. http://dx.doi.org/10.1039/np9870400175.

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21

Kurtboke, Ipek. "Microbial systematics." Microbiology Australia 32, no. 2 (2011): 58. http://dx.doi.org/10.1071/ma11058.

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This special issue of Microbiology Australia covers microbial systematics. In guest-editing this issue my intention has been to bring world experts together to discuss the past, present and future of microbial systematics with a view on the technical and theoretical advancements in the field. While the global debate continues on how to define ?microbial species? in the light of recent advances, expert authors contribute insights into how sound taxonomical analyses can benefit this process of redefinition.

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22

Nieragden, Göran. "Literary Systematics." Language and Literature: International Journal of Stylistics 2, no. 3 (August 1993): 223–25. http://dx.doi.org/10.1177/096394709300200306.

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23

Stokoe, Elizabeth. "Categorial systematics." Discourse Studies 14, no. 3 (June 2012): 345–54. http://dx.doi.org/10.1177/1461445612441543.

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In this response article, I focus on two issues. First, I discuss the problem, raised by the commentators, of ‘categorial ambiguity’ in membership categorization analysis, and make suggestions about how to approach it. Second, I argue that, as conversation analysts have demonstrated the ‘systematics’ of interactional practices, membership categorization analysis should also begin to build a robust corpus of studies of ‘categorial systematics’.

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24

Davison, Andrew J. "Herpesvirus systematics." Veterinary Microbiology 143, no. 1 (June 2010): 52–69. http://dx.doi.org/10.1016/j.vetmic.2010.02.014.

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25

Eubanks, Mary. "Molecular systematics." Economic Botany 52, no. 2 (April 1998): 133. http://dx.doi.org/10.1007/bf02861200.

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26

Pääbo, Svante. "Molecular systematics." Trends in Genetics 7, no. 8 (August 1991): 272. http://dx.doi.org/10.1016/0168-9525(91)90328-n.

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27

Berenbaum, May. "Super Systematics." American Entomologist 41, no. 2 (1995): 68–69. http://dx.doi.org/10.1093/ae/41.2.68.

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28

Schouest, Leo P. "Molecular Systematics." Annals of the Entomological Society of America 85, no. 4 (July 1, 1992): 536. http://dx.doi.org/10.1093/aesa/85.4.536.

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29

Manuel, O., M. Pleess, Y. Singh, and W. A. Myers. "Nuclear systematics." Journal of Radioanalytical and Nuclear Chemistry 266, no. 2 (November 2005): 159–63. http://dx.doi.org/10.1007/s10967-005-0887-2.

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30

Ayala, Francisco J. "Molecular systematics." Journal of Molecular Evolution 34, no. 3 (March 1992): 274–76. http://dx.doi.org/10.1007/bf00162977.

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31

Kluge, Arnold G. "Genealogical Systematics." Genealogy 7, no. 1 (February 20, 2023): 11. http://dx.doi.org/10.3390/genealogy7010011.

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Genealogical research usually begins with the discovery of affinity among individual humans. Such kinship is induced by direct observation, as well as by hearsay (indirect observation) that can be independently confirmed. Those who want to continue investigating a case history after the observational mode of fact-finding is no longer sustainable have no other choice than to switch to the discovery of consanguineous relationships. This involves a paradigm shift, where investigation dramatically changes from observation to inference, from inductive to deductive reasoning. Individuation is important in characterizing the personhood of an individual, but those same facts are of little empirical value in establishing the unification of a family. In addition, genealogists rely on marriage as an observable source of evidence for unification. However, this extrapolation is not completely convincing because marriage does not take into account the uncertainty of paternity. Individual parents usually descend from different parts of family history, which suggests genealogists should evaluate cultural factors responsible for non-random mating in attempting to infer consanguinity. For example, there is the incest taboo, a cultural convention which addresses the abnormal genetic consequences of inbreeding. Other non-random mating factors of a more general nature may also be identified in the unification of genetically different individuals. Here, for example, causality is expected in cultural principles that are of a cohesive and integrative nature. Those kinds of evidence may determine an unmarried pair’s earliest engagement and may also be responsible for the origin and maintenance of the marriage relationship, even throughout post-reproductive life. Lastly, current genealogical research is severely infected with confirmation bias, and from which it must be protected if it is to achieve the status of a scientific discipline. Critical rationalism provides a solution to that kind of problem. It is with remediation in mind, as it applies to all of the aforementioned issues, that genealogical systematics is characterized.

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32

Small, Ernest. "SYSTEMATICS OF BIOLOGICAL SYSTEMATICS (OR, TAXONOMY OF TAXONOMY)." TAXON 38, no. 3 (August 1989): 335–56. http://dx.doi.org/10.2307/1222265.

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33

Reif, Wolf-Ernst. "Problematic issues of cladistics: 9. Hennig’s “Phylogenetic Systematics”." Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 235, no. 3 (April 21, 2005): 289–342. http://dx.doi.org/10.1127/njgpa/235/2005/289.

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34

Pandey, Arun K., Tod F. Stuessy, and Roshni R. Mathur. "Phytomelanin and Systematics of the Heliantheae Alliance (Compositae)." Plant Diversity and Evolution 131, no. 3 (April 1, 2014): 145–65. http://dx.doi.org/10.1127/1869-6155/2014/0131-0077.

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35

Glanville, Aaron, Cullan Howlett, and Tamara M. Davis. "The effect of systematic redshift biases in BAO cosmology." Monthly Notices of the Royal Astronomical Society 503, no. 3 (March 8, 2021): 3510–21. http://dx.doi.org/10.1093/mnras/stab657.

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ABSTRACT With the remarkable increase in scale and precision provided by upcoming galaxy redshift surveys, systematic errors that were previously negligible may become significant. In this paper, we explore the potential impact of low-magnitude systematic redshift offsets on measurements of the Baryon Acoustic Oscillation (BAO) feature, and the cosmological constraints recovered from such measurements. Using 500 mock galaxy redshift surveys as our baseline sample, we inject a series of systematic redshift biases (ranging from $\pm 0.2{{\ \rm per\ cent}}$ to $\pm 2{{\ \rm per\ cent}}$), and measure the resulting shift in the recovered isotropic BAO scale. When BAO measurements are combined with CMB constraints across a range of cosmological models, plausible systematics introduce a negligible offset on combined fits of H0 and Ωm, and systematics must be an order of magnitude greater than this plausible baseline to introduce a 1σ shift on such combined fits. We conclude that systematic redshift biases are very unlikely to bias constraints on parameters such as H0 provided by BAO cosmology, either now or in the near future. We also detail a theoretical model that predicts the impact of uniform redshift systematics on α, and show this model is in close alignment with the results of our mock survey analysis.

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36

Almoubayyed, Husni, Rachel Mandelbaum, Humna Awan, Eric Gawiser, R. Lynne Jones, Joshua Meyers, J. Anthony Tyson, and Peter Yoachim. "Optimizing LSST observing strategy for weak lensing systematics." Monthly Notices of the Royal Astronomical Society 499, no. 1 (September 21, 2020): 1140–53. http://dx.doi.org/10.1093/mnras/staa2879.

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ABSTRACT The Legacy Survey of Space and Time (LSST) survey will provide unprecedented statistical power for measurements of dark energy. Consequently, controlling systematic uncertainties is becoming more important than ever. The LSST observing strategy will affect the statistical uncertainty and systematics control for many science cases; here, we focus on weak lensing (WL) systematics. The fact that the LSST observing strategy involves hundreds of visits to the same sky area provides new opportunities for systematics mitigation. We explore these opportunities by testing how different dithering strategies (pointing offsets and rotational angle of the camera in different exposures) affect additive WL shear systematics on a baseline operational simulation, using the ρ-statistics formalism. Some dithering strategies improve systematics control at the end of the survey by a factor of up to ∼3–4 better than others. We find that a random translational dithering strategy, applied with random rotational dithering at every filter change, is the most effective of those strategies tested in this work at averaging down systematics. Adopting this dithering algorithm, we explore the effect of varying the area of the survey footprint, exposure time, number of exposures in a visit, and exposure to the Galactic plane. We find that any change that increases the average number of exposures (in filters relevant to WL) reduces the additive shear systematics. Some ways to achieve this increase may not be favorable for the WL statistical constraining power or for other probes, and we explore the relative trade-offs between these options given constraints on the overall survey parameters.

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37

Small, Ernest. "The economic value of plant systematics in Canadian agriculture." Canadian Journal of Botany 71, no. 12 (December 1, 1993): 1537–51. http://dx.doi.org/10.1139/b93-188.

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Agriculture is like a house, resting on a foundation of biological systematics. That foundation is seriously deteriorating, in part because of lack of appreciation of its vital roles and economic relevance. Support for biological sciences is concentrating in seemingly lucrative disciplines, without much realization that the financial benefits often can not be realized without the materials and information provided by systematics. A variety of considerations supports the economic wisdom of investing in systematics research in Canada, most particularly on behalf of the agricultural sector, and suggest that failure to do so could lead to serious, even catastrophic, consequences. In particular, the present scarcity of expertise for identification of vanishing invaluable wild crop germ plasm may permanently penalize both agriculture and society. While it is essential that systematists retain their fundamental orientation to the clarification and cataloging of biological diversity, emphasis on the useful roles played and products produced is both an economic necessity and a social responsibility. Key words: plant, systematics, taxonomy, agriculture, economic.

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38

Edwards, Trevor. "Advances in Legume Systematics, Part 10: Higher Level Systematics." South African Journal of Botany 71, no. 3-4 (November 2005): 453. http://dx.doi.org/10.1016/s0254-6299(15)30123-x.

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39

Petersen, Ronald H. "Contributions of mating studies to mushroom systematics." Canadian Journal of Botany 73, S1 (December 31, 1995): 831–42. http://dx.doi.org/10.1139/b95-329.

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Three general topics are included. First, a summary of knowledge of mating systems in several genera is furnished, with discussion concerning individual species. Second, the consequence of mating studies in expansion or contraction of numbers of accepted names is discussed. Inherent in this topic is the species concept to be used by the systematis. Third, guidelines for establishment of standard batteries of tester strains are outlined, using Pleurotus as an example. Key words: mating systems, Agaricales, Pleurotus, systematics.

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40

Scudder, G. G. E. "The next 25 years: invertebrate systematics." Canadian Journal of Zoology 65, no. 4 (April 1, 1987): 786–93. http://dx.doi.org/10.1139/z87-125.

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A distinction is made between classification, taxonomy, and systematics. Taxonomic studies in most invertebrate groups will not progress beyond the descriptive stages because of the large number of species to be described, the low profile of taxonomy, and the lack of support for museums. Taxonomy and classification must be seen as immediate economic components of modern biology: systematics should be revived in the universities. The limitations of the morphospecies concept make studies on living forms, freshly killed animals, or specially preserved specimens imperative, but these cannot be completed except in very few instances. Hence we are likely to learn more and more about less and less. Nevertheless, more sibling species complexes will undoubtedly be discovered. When these complexes are understood systematically, and population genetics becomes integrated with the study of speciation, more emphasis will likely be given to the multiplicity of speciation models. A pleuralistic definition of species should follow. Cladistic systematics will continue to expand in the invertebrates. More emphasis should be placed on early Metazoan fossils, and attempts made to fit them into classifications. Fossils can be useful in checking various phylogenetic models, even if they are considered useless for determining evolutionary relationships by some cladists. With the current acceptance that the Protista and Protozoa are both polyphyletic, there will be a major revolution in invertebrate systematics. Ultrastructural and biochemical data are needed to clarify the systematics of both the unicellular eukaryotes and multicellular Metazoa. Only after systematic analyses of wider data sets are complete will it be time to consider a new classification for the "invertebrates." However, the resulting scheme will be very different from that which we accept, follow, and teach today.

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41

HODDA, M. "Phylum Nematoda: trends in species descriptions, the documentation of diversity, systematics, and the species concept." Zootaxa 5114, no. 1 (March 10, 2022): 290–317. http://dx.doi.org/10.11646/zootaxa.5114.1.2.

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This paper summarizes the trends in nematode species description and systematics emerging from a comparison of the latest comprehensive classification and census of Phylum Nematoda (Hodda 2022a, b) with earlier classifications (listed in Hodda 2007). It also offers some general observations on trends in nematode systematics emerging from the review of the voluminous literature used to produce the classification. The trends in nematodes can be compared with developments in the systematics of other organisms to shed light on many of the general issues confronting systematists now and into the future.

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42

Heckeberg, Nicola S. "The systematics of the Cervidae: a total evidence approach." PeerJ 8 (February 18, 2020): e8114. http://dx.doi.org/10.7717/peerj.8114.

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Systematic relationships of cervids have been controversial for decades. Despite new input from molecular systematics, consensus could only be partially reached. The initial, gross (sub) classification based on morphology and comparative anatomy was mostly supported by molecular data. The rich fossil record of cervids has never been extensively tested in phylogenetic frameworks concerning potential systematic relationships of fossil cervids to extant cervids. The aim of this work was to investigate the systematic relationships of extant and fossil cervids using molecular and morphological characters and make implications about their evolutionary history based on the phylogenetic reconstructions. To achieve these objectives, molecular data were compiled consisting of five nuclear markers and the complete mitochondrial genome of 50 extant and one fossil cervids. Several analyses using different data partitions, taxon sampling, partitioning schemes, and optimality criteria were undertaken. In addition, the most extensive morphological character matrix for such a broad cervid taxon sampling was compiled including 168 cranial and dental characters of 41 extant and 29 fossil cervids. The morphological and molecular data were analysed in a combined approach and other comprehensive phylogenetic reconstructions. The results showed that most Miocene cervids were more closely related to each other than to any other cervids. They were often positioned between the outgroup and all other cervids or as the sister taxon to Muntiacini. Two Miocene cervids were frequently placed within Muntiacini. Plio- and Pleistocene cervids could often be affiliated to Cervini, Odocoileini or Capreolini. The phylogenetic analyses provide new insights into the evolutionary history of cervids. Several fossil cervids could be successfully related to living representatives, confirming previously assumed affiliations based on comparative morphology and introducing new hypotheses. New systematic relationships were observed, some uncertainties persisted and resolving systematics within certain taxa remained challenging.

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43

McCallum, Nialh, Daniel B. Thomas, Philip Bull, and Michael L. Brown. "Spin-based removal of instrumental systematics in 21 cm intensity mapping surveys." Monthly Notices of the Royal Astronomical Society 508, no. 4 (October 2, 2021): 5556–77. http://dx.doi.org/10.1093/mnras/stab2811.

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ABSTRACT Upcoming cosmological intensity mapping surveys will open new windows on the Universe, but they must first overcome a number of significant systematic effects, including polarization leakage. We present a formalism that uses scan strategy information to model the effect of different instrumental systematics on the recovered cosmological intensity signal for ‘single-dish’ (autocorrelation) surveys. This modelling classifies different systematics according to their spin symmetry, making it particularly relevant for dealing with polarization leakage. We show how to use this formalism to calculate the expected contamination from different systematics as a function of the scanning strategy. Most importantly, we show how systematics can be disentangled from the intensity signal based on their spin properties via map-making. We illustrate this, using a set of toy models, for some simple instrumental systematics, demonstrating the ability to significantly reduce the contamination to the observed intensity signal. Crucially, unlike existing foreground removal techniques, this approach works for signals that are non-smooth in frequency, e.g. polarized foregrounds. These map-making approaches are simple to apply and represent an orthogonal and complementary approach to existing techniques for removing systematics from upcoming 21 cm intensity mapping surveys.

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44

Silfverberg, Hans, Toomas Tammaru, and Juhani Itämies. "Reviews: Catalogue of Ceutorhynchinae of the World, with a key to Genera, The Geometrid Moths of Europe, Die Larven der Europäeischen Noctuidae." Entomologica Fennica 16, no. 4 (December 1, 2005): 317–20. http://dx.doi.org/10.33338/ef.84279.

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Colonnelli, E. 2004: Catalogue of Ceutorhynchinae of the World, with a key to Genera. – Argania Editio, Barcelona. 124 pp. ISBN 84- 931847-6-4. Price 80 EUR. Hausmann, A. 2004: The Geometrid Moths of Europe, Vol. 2: Sterrhinae. Apollo Books, Kirkeby Sand 19, DK-5771 Stenstrup, Denmark. ISBN 87-88757-37-4, Hardback, 600 pp. Price 960,00 DKK. Beck, H. 1999–2000: Die Larven der Europäeischen Noctuidae. Revision der Systematik der Noctuidae (Larvae of European Noctuidae. Revision of the systematics of the Noctuidae). With the help of Matti Ahola (numerous drawings) and Ivar Hasenfuss (systematic notes on Noctuoidea, Acronictinae, and occasional drawings). Volumes I–IV. 864+448+336+512 pp. ISSN 0723-595X, ISBN 3-923807-04-X. Price 530 EUR.

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Fu, Jing, Carl Sondergeld, and Chandra Rai. "Core-Derived Velocity Systematics, Mississippian Meramec Formation, Oklahoma." SPE Journal 27, no. 01 (November 11, 2021): 705–14. http://dx.doi.org/10.2118/206753-pa.

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Summary Elastic wave velocities are commonly used to predict porosity, mineralogy, and lithology from formation properties. When only P-wave sonics are available in historical wells, systematics for predicting shear velocities are useful for developing elastic models. Although much research has been done on conventional reservoir velocity systematics, the equivalency for unconventional formations is still a work in progress. There has also been a limited number of research studies with laboratory measures published. Using laboratory pulse transmission ultrasonic data, we created a Vp-Vs systematic for the Meramec Formation in this study. The effects of porosity and mineralogy on velocities are explored, as well as a comparison of Meramec velocity systematics with well-established literature systematics. Vp and Vs measurements were taken on 385 dodecane-saturated core samples from seven Meramec wells (106 vertical and 279 horizontal plugs). S-wave and P-wave anisotropy in Meramec Formation samples used in this study are typically less than 10%. Each sample was also tested for porosity and mineralogy. We find that velocities are more sensitive to porosity than mineralogy by a factor of 10. Below are our equations for predicting Vp and Vs (in km/s), when only clay content and porosity are known. In these equations, φ is the volume fraction pores, and Clays is the weight fraction of clay. These equations are for those samples in which there is low P-wave and S-wave anisotropies:(1)Vp=6.4−1.2*Clays−15.4*φ(R2=0.5),(2)Vs=3.6−0.5*Clays−5.2*φ(R2=0.4). We suggest two methods for calculating Vs from Vp: Ignoring anisotropy, we combined both Vp and Vs measurements from all vertical plugs and low anisotropy horizontal plugs to create a single shear wave predictor; and considering anisotropy, Vp measurements from horizontal plugs were corrected using Thomsen’s compressional wave anisotropy parameter, after which a shear velocity predictor was generated. The shear wave predictors for dodecane-saturated measurements are as follows (all velocities are km/s):(3)Method 1: Vs= 0.90 + 0.42*Vp (R2=0.7),(4)Method 2: Vs= 0.80 + 0.45*Vp (R2=0.6). The residual and estimated error in Eq. 3 is slightly less than in Eq. 4. Even though there is a significant variance in measurement frequency, the Meramec velocity systematic shows good agreement with dipole wireline measurements using the first equation. The Meramec velocity systematics differ significantly from previously published systematics, such as the trend line by Greenberg and Castagna (1992) and the shale trend line by Vernik et al. (2018). Using the correlations by Greenberg and Castagna (1992) for limestone or dolomite, the shear velocities of the samples in this study cannot be predicted. These data have yielded shear wave systematics, which can be used in wireline and seismic investigations. The results suggest that the method of ignoring anisotropy yields a better Vs estimate than the one that takes anisotropy into account. Using well-established shear wave velocity systematics from the published literature can result in an estimated inaccuracy of greater than 16%. It is important to calibrate velocity systematics to the target formation.

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Hausen, Harald, and Christoph Bleidorn. "Significance of chaetal arrangement for maldanid systematics (Annelida, Maldanidae)." Scientia Marina 70, S3 (December 30, 2006): 75–79. http://dx.doi.org/10.3989/scimar.2006.70s375.

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Zurwerra, A., M. Metzler, and I. Tomka. "Biochemical systematics and evolution of the European Heptageniidae (Ephemeroptera)." Archiv für Hydrobiologie 109, no. 4 (July 6, 1987): 481–510. http://dx.doi.org/10.1127/archiv-hydrobiol/109/1987/481.

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Voelker, Gary, and John Klicka. "Systematics of Zoothera thrushes, and a synthesis of true thrush molecular systematic relationships." Molecular Phylogenetics and Evolution 49, no. 1 (October 2008): 377–81. http://dx.doi.org/10.1016/j.ympev.2008.06.014.

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Wilson, Paul. "Evolutionary Systematics Exemplified." Bryologist 121, no. 3 (September 2018): 456–58. http://dx.doi.org/10.1639/0007-2745-121.3.456.

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Starobogatov, Ya I., and Mark J. Grygier. "Systematics of Crustacea." Journal of Crustacean Biology 8, no. 2 (April 1, 1988): 300–311. http://dx.doi.org/10.2307/1548322.

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