Summary of Basic Equations for N Independent Species

Author(s):  
Morton E. Gurtin ◽  
Eliot Fried ◽  
Lallit Anand
1961 ◽  
Vol 38 (3) ◽  
pp. 469-472 ◽  
Author(s):  
K. R. Laumas ◽  
J. F. Tait ◽  
S. A. S. Tait

ABSTRACT Reconsideration of the question of the validity of the calculations of the secretion rates from the specificity activity of a urinary metabolite after the single injection of a radioactive hormone has led us to conclude that the basic equations used in a previous theoretical treatment are not generally applicable to the nonisotopic steady state if the radioactive steroid and hormone are introduced into the same compartment. If this is so, in a two compartmental model with metabolism occurring in both pools, it is now shown that the calculation (S = R — τ) is rigorously valid if certain precautions are taken. This is in contrast to the previous treatment which concluded (in certain special circumstances) that the calculation might not be correct. However, if the hormone is secreted in both compartments and the radioactive steroid is injected into only one, then the calculation (S = R — τ) may not be correct in certain circumstances as was previously concluded (Laumas et al. 1961).


2019 ◽  
Vol 44 (4) ◽  
pp. 753-767
Author(s):  
Tian-Chuan Hsu ◽  
Yu-Fang Huang ◽  
Yi-Shan Chao

Abstract—Hymenophyllum subg. Mecodium, composed of the taxonomically notorious H. polyanthos and approximately 15 other closely related taxa, is a common element of filmy fern communities in the tropical and subtropical moist forests. In Taiwan, although only H. polyanthos and one or two closely related taxa were recognized in recent studies, considerable morphological variation has been observed among populations throughout the island. Thus, we conducted an extensive morphological investigation, as well as a molecular phylogenetic analysis, to clarify the specific diversity and phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan. Field and herbaria surveys helped in recognizing five morphs in Taiwan, mainly differentiated by the combination of certain traits, viz., the presence or absence of stipe wings, general frond size and shape, degree of laminar crispation, sori position, and involucre shape. The different morphs had diverse ecological preferences. The phylogenetic tree, inferred from the sequences of the plastid loci rbcL and rps4-trnS, demonstrated that Hymenophyllum subg. Mecodium materials in Taiwan comprise several well-supported lineages, mostly corresponding to the classification based on morphology. Comparing with the protologues and type specimens of 34 related scientific names, the five morphs are herein recognized as five independent species. A new species, Hymenophyllum exquisitum, is described here. Also, the status of H. paniculiflorum is reconfirmed and that of H. fujisanense, H. parallelocarpum, and H. punctisorum reinstated. Only H. exquisitum and H. parallelocarpum are endemic to Taiwan among all the species studied. In addition, the names Hymenophyllum blumeanum, H. integrum, H. microsorum, H. polyanthos, H. tenellum, and H. wrightii are now excluded from the regional flora, and several related taxa from China, Taiwan, and the Philippines are treated as synonyms. This study unravels the deep phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan and Eastern Asia.


2014 ◽  
Vol 48 ◽  
pp. 256-263 ◽  
Author(s):  
O. A. Kataeva

Ramalina sekika Asahina is reported for the first time from Russia from Sakhalin. It refers to the number of rare and poorly investigated species of the genus. Until now it was considered to be endemic to northeastern China. The original description and the location in the Far East are given, as well as the data on anatomical and morphological study of the Russian specimen. The differences in the anatomical structure of its thallus are discussed. A comparison of anatomical and morphological characters of R. sekika, R. pollinaria (Westr.) Ach. (European material), R. yasudae Räsänen has been made; the author considers them as independent species.


Zootaxa ◽  
2009 ◽  
Vol 2141 (1) ◽  
pp. 56-68 ◽  
Author(s):  
CSABA CSUZDI ◽  
MARTINEZ ARNAUTH GUEI ◽  
JÉRÔME EBAGNERIN TONDOH

A recent survey in the main habitat types of Mt. Nimba, Guinea (upland prairie, Serengbara forest and piedmont savannah) resulted in recording of 13 earthworm species of which 9 are first reported after the original description and three, Dichogaster (Dichogaster) cornuta sp. n., Guineoscolex geminatus sp. n. and Guineoscolex ungulatus sp. n., proved to be new to science. On the basis of the new material collected Benhamia inaequalis f. nimbai Omodeo is redescribed and resurrected from synonymy of Guineoscolex inaequalis (Michaelsen) as an independent species Guineoscolex nimbai (Omodeo). With 17 original figures.


2019 ◽  
Vol 968 ◽  
pp. 496-510
Author(s):  
Anatoly Grigorievich Zelensky

Classical and non-classical refined theories of plates and shells, based on various hypotheses [1-7], for a wide class of boundary problems, can not describe with sufficient accuracy the SSS of plates and shells. These are boundary problems in which the plates and shells undergo local and burst loads, have openings, sharp changes in mechanical and geometric parameters (MGP). The problem also applies to such elements of constructions that have a considerable thickness or large gradient of SSS variations. The above theories in such cases yield results that can differ significantly from those obtained in a three-dimensional formulation. According to the logic in such theories, the accuracy of solving boundary problems is limited by accepted hypotheses and it is impossible to improve the accuracy in principle. SSS components are usually depicted in the form of a small number of members. The systems of differential equations (DE) obtained here have basically a low order. On the other hand, the solution of boundary value problems for non-thin elastic plates and shells in a three-dimensional formulation [8] is associated with great mathematical difficulties. Only in limited cases, the three-dimensional problem of the theory of elasticity for plates and shells provides an opportunity to find an analytical solution. The complexity of the solution in the exact three-dimensional formulation is greatly enhanced if complex boundary conditions or physically nonlinear problems are considered. Theories in which hypotheses are not used, and SSS components are depicted in the form of infinite series in transverse coordinates, will be called mathematical. The approximation of the SSS component can be adopted in the form of various lines [9-16], and the construction of a three-dimensional problem to two-dimensional can be accomplished by various methods: projective [9, 14, 16], variational [12, 13, 15, 17]. The effectiveness and accuracy of one or another variant of mathematical theory (MT) depends on the complex methodology for obtaining the basic equations.


Zootaxa ◽  
2019 ◽  
Vol 4568 (3) ◽  
pp. 581 ◽  
Author(s):  
SERGEY G. ERMILOV ◽  
ELIZABETH A. HUGO-COETZEE

The main morphological traits of Galumna lawrencei Jacot, 1940 stat. nov. and Galumna natalensis Jacot, 1940 stat. nov. (Oribatida, Galumnidae) are presented based on the type material from South Africa. We consider that these species are not subspecies of Galumna maxima as was proposed originally by Jacot 1940, but independent species. A lectotype for G. lawrencei is designated, due to the mixed-species cotype series. 


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