Fern speciation and biogeography

1985 ◽  
Vol 86 ◽  
pp. 353-360 ◽  
Author(s):  
Rolla Tryon
Keyword(s):  
New Species ◽  
Parental Species ◽  
Local Environment ◽  
Limited Range ◽  
Ecological Adaptation ◽  
Species Selection ◽  
Potential Range ◽  
Small Range ◽  
Extensive Range ◽  
Selection Of

SynopsisThe most common kinds of speciation result in new species that initially have a small range. These will develop a limited or an extensive range depending upon the geographic extent of the environment to which they are adapted. A significant element in the extent of the potential range of a new species is the adaptation inherited from the parental species. Selection of a parental species for a local environment at one site can lead to a narrow ecological adaptation and often to a limited potential range. These species are likely to produce derived ones that also have a limited range, and these derivates will increase the regional species endemism and diversity. Selection of a parental species for migration to other sites can lead to a broader ecological adaptation and often to a broad potential range. These species are more likely to produce derived ones that also have an extensive range, and these derivates will increase regional species diversity.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

scholarly journals Thermo-economic comparative analysis of gas turbine GT10 integrated with air and steam bottoming cycle

2014 ◽  
Vol 35 (4) ◽  
pp. 83-95 ◽  
Author(s):  
Daniel Czaja ◽  
Tadeusz Chmielnak ◽  
Sebastian Lepszy
Keyword(s):  
Economic Analysis ◽  
Gas Turbine ◽  
Power Plants ◽  
Combined Cycle ◽  
Small Range ◽  
Exhaust Gas ◽  
Thermodynamic Optimization ◽  
Technological Structure ◽  
The Cost ◽  
Selection Of

Abstract A thermodynamic and economic analysis of a GT10 gas turbine integrated with the air bottoming cycle is presented. The results are compared to commercially available combined cycle power plants based on the same gas turbine. The systems under analysis have a better chance of competing with steam bottoming cycle configurations in a small range of the power output capacity. The aim of the calculations is to determine the final cost of electricity generated by the gas turbine air bottoming cycle based on a 25 MW GT10 gas turbine with the exhaust gas mass flow rate of about 80 kg/s. The article shows the results of thermodynamic optimization of the selection of the technological structure of gas turbine air bottoming cycle and of a comparative economic analysis. Quantities are determined that have a decisive impact on the considered units profitability and competitiveness compared to the popular technology based on the steam bottoming cycle. The ultimate quantity that can be compared in the calculations is the cost of 1 MWh of electricity. It should be noted that the systems analyzed herein are power plants where electricity is the only generated product. The performed calculations do not take account of any other (potential) revenues from the sale of energy origin certificates. Keywords: Gas turbine air bottoming cycle, Air bottoming cycle, Gas turbine, GT10

Individuals, hierarchies and processes: towards a more complete evolutionary theory

Paleobiology ◽  
1984 ◽  
Vol 10 (2) ◽  
pp. 146-171 ◽  
Author(s):  
Elisabeth S. Vrba ◽  
Niles Eldredge
Keyword(s):  
Downward Causation ◽  
Species Selection ◽  
Process Selection ◽  
Term Selection ◽  
Hierarchical Levels ◽  
Character Variation ◽  
Long Term Trend ◽  
Interlevel Causation ◽  
Selection Of

Hierarchy is a central phenomenon of life. Yet it does not feature as such in traditional biological theory. The genealogical hierarchy is a nested organization of entities at ascending levels. There are phenomena common to all levels: (1) Entities such as genomic constituents, organisms, demes, and species are individuals. (2) They have aggregate characters (statistics of characters of subparts), but also emergent characters (arising from organization among subparts). Character variation changes by (3) introduction of novelty and (4) sorting by differential birth and death. Causation of introduction and sorting of variation at each level may be (5) upward from lower levels, (6) downward from higher levels, or (7) lodged at the focal level. The term “selection” applies to only one of the possible processes which cause sorting at a focal level. Neo-Darwinian explanations are too narrow, both in the levels (of genotypes and phenotypes) and in the directive process (selection) which are stressed. The acknowledgment of additional, hierarchical phenomena does not usually extend beyond lip service. We urge that interlevel causation should feature centrally in explanatory hypotheses of evolution. For instance, a ready explanation for divergence in populations is “selection of random mutants.” But upward causation from genome dynamics (or downward causation from the hierarchical organism) to the directed introduction of mutants may be more important in a given case. Similarly, a long-term trend is traditionally explained as additive evolution in populations. But sorting among species may be the cardinal factor, and the cause may not be species selection but upward causation from lower levels. A general theory of biology is a theory of hierarchical levels—how they arise and interact. This is a preliminary contribution mainly to the latter question.

Phytodiversity of the "Samara plavni" regional landscape park

2020 ◽  
Vol 49 ◽  
pp. 17-25
Author(s):  
B. A. Baranovski ◽  
I. A. Ivanko ◽  
L. O. Karmyzova ◽  
Y. A. Harvart ◽  
V. V. Nicolaieva ◽  
...  
Keyword(s):  
Invasive Species ◽  
Vascular Plants ◽  
Vascular Plant ◽  
Species Selection ◽  
Submerged Vegetation ◽  
Surrounding Area ◽  
Adventive Flora ◽  
Regional Landscape ◽  
Natural Groups ◽  
Selection Of

Рresented the results of floroecological, hydrobotanical and geobotanical researches of the Regional Landscape Park "Samara Plavni". Regional Landscape Park (RLP) "Samara Plavni" is located in the waters of the Samara Bay, which was formed as a result of flooding of the floodplain of the Samara River during the creation of the Zaporozhye (Dnieper) Reservoir and the surrounding area. Conducted a systematic and bioecological analysis of the flora of vascular plants. Studied the composition of the rare fraction of flora and associated flora element. The research was carried out according to the generally accepted methods of floristic, geobotanical and hydrobotanical research. Bioecomorphic characteristics of species (selection of ecomorphs) are compiled according by A. L. Belgard ecomorph system using the following ecomorphs: biomorphs (one-, two-, perennials); heliomorphs (relation to light); hygromorphs (relation to the aquatic environment); tropomorphs (relation to nutrition); cenomorphs (growth in certain phytocenoses). Ecological characteristics of species were given from literature sources and according to the results of many years of own research. The analysis of the adventitious fraction was carried out at the time of drift – archaeophytes, neophytes. Advent status was determined on the basis of literature data. Vegetation of the regional landscape park "Samara Plavni" is represented by natural and semi-natural groups. The main area of shallow water is occupied by massifs of Phragmites australis (Cav.) Trin. ex Steud and groups of submerged vegetation. The tree and shrub vegetation of the park is represented by natural forest complexes, semi-natural groups and artificial plantations. Meadow and meadow-swamp vegetation of the landscape park is represented by complexes of associations of mesophytes and hygrophytes. The floristic list of vascular plant flora is 617 species. Hemicryptophytes, perennials, sciogeliophytes and heliophytes, mesotrophs, mesophytes, hygrophytes predominate here. Among cenomorphs, most species are represented by meadow (139) and forest (108) species. The rare fraction of flora is 73 species. There are 128 species of ruderal flora and 140 species of adventive flora, including 6 invasive species. At the time of entry into the study area allochthonous element of flora is divided into two groups: archaeophytes – 63 species (45%) and neophytes – 77 species (55%).

scholarly journals The Weevil Fauna Preserved in Burmese Amber—Snapshot of a Unique, Extinct Lineage (Coleoptera: Curculionoidea)

Diversity ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 1 ◽  
Author(s):  
Dave Clarke ◽  
Ajay Limaye ◽  
Duane McKenna ◽  
Rolf Oberprieler
Keyword(s):  
New Species ◽  
Light Microscopy ◽  
Fossil Record ◽  
Ct Scanning ◽  
High Magnification ◽  
New Genera ◽  
Burmese Amber ◽  
Critical Gap ◽  
Selection Of

Only a few weevils have been described from Burmese amber, and although most have been misclassified, they show unusual and specialised characters unknown in extant weevils. In this paper, we present the results of a study of a much larger and more diverse selection of Burmese amber weevils. We prepared all amber blocks to maximise visibility of structures and examined these with high-magnification light microscopy as well as CT scanning (selected specimens). We redescribe most previously described taxa and describe 52 new species in 26 new genera, accompanied by photographs. We compare critical characters of these weevils with those of extant taxa and outline the effects of distortion on their preservation and interpretation. We conclude that only two weevil families are thus far represented in Burmese amber, Nemonychidae and a newly recognised family, Mesophyletidae, which appears closely related to Attelabidae but cannot be accommodated in this family. The geniculate antennae and long rostrum with exodont mandibles of most Mesophyletidae indicate that they were highly specialised phytophages of early angiosperms preserved in the amber, likely ovipositing in flowers or seeds. This weevil fauna appears to represent an extinct mid-Cretaceous ecosystem and fills a critical gap in the fossil record of weevils.

Selection of Lipase-Producing Microorganisms through Submerged Fermentation

2010 ◽  
Vol 65 (7-8) ◽  
pp. 483-488 ◽  
Author(s):  
Luciane Maria Colla ◽  
Andreiza Lazzarotto Primaz ◽  
Silvia Benedetti ◽  
Raquel Aparecida Loss ◽  
Marieli de Lima ◽  
...  
Keyword(s):  
New Species ◽  
Submerged Fermentation ◽  
Lipolytic Activity ◽  
Diesel Oil ◽  
Enzyme Extract ◽  
Dairy Effluent ◽  
Catalytic Activities ◽  
Industrial Sectors ◽  
Selection Of Microorganisms ◽  
Selection Of

Lipases are enzymes used in various industrial sectors such as food, pharmaceutical and chemical synthesis industries. The selection of microorganisms isolated from soil or wastewater is an alternative to the discovery of new species with high enzymes productivity and with different catalytic activities. In this study, the selection of lipolytic fungi was carried out by submerged fermentation. A total of 27 fungi were used, of which 20 were isolated from dairy effluent and 7 from soil contaminated with diesel oil. The largest producers were the fungi Penicillium E-3 with maximum lipolytic activity of 2.81 U, Trichoderma E-19 and Aspergillus O-8 with maximum activities of 2.34 and 2.03 U where U is the amount of enzyme that releases 1 μmol of fatty acid per min per mL of enzyme extract. The fungi had maximum lipolytic activities on the 4th day of fermentation.

Species selection of pre-amorphous implantation in Nickle Silicide process

2015 ◽  
Author(s):  
Qiu Yuming ◽  
Yu Deqin ◽  
Cao Wenjie ◽  
Xiao Tianjin ◽  
He Zhibin ◽  
...  
Keyword(s):  
Species Selection ◽  
Selection Of

scholarly journals Oenothera oehlkersii Kappus ex Rostański - a new evening-primrose species in Polish flora

2011 ◽  
Vol 23 (1) ◽  
pp. 57-58
Author(s):  
Mateusz Wolanin ◽  
Monika Woźniak
Keyword(s):  
New Species ◽  
Parental Species ◽  
Evening Primrose ◽  
A New Species

Oenothera oehlkersii Kappus ex Rostański - a new evening-primrose species in Polish flora Oenothera oehlkersii Kappus ex Rostański - a new species of Polish flora - was found on the Przemyśl Foothills. The species is a hybrid between Oe. glazioviana Micheli in Mart. and Oe. suaveolens Desf. ex Pers. In this paper, authors present some features useful in recognizing the parental species and the hybrid one.

Two new species of Tricoryne (Hemerocallidaceae) from the Midwest region of Western Australia

2014 ◽  
Vol 27 (6) ◽  
pp. 415 ◽  
Author(s):  
Terry D. Macfarlane ◽  
Gregory J. Keighery
Keyword(s):  
New Species ◽  
Western Australia ◽  
Field Studies ◽  
Separate Species ◽  
Remnant Vegetation ◽  
Two New Species ◽  
Extensive Range ◽  
Taxonomic Concept ◽  
Midwest Region ◽  
Fibrous Roots

Field studies have provided an improved understanding of a known undescribed species of Tricoryne R.Br. and also shown that two or three separate species are included in an existing taxonomic concept. Two new species are described here, namely, T. tuberosa Keighery & T.D.Macfarl. and T. soullierae T.D.Macfarl. & Keighery. Tricoryne tuberosa has an extensive range in the northern wheatbelt and adjacent pastoral areas of south-western Western Australia. It has large root tubers, the leaves are withered at flowering time, and it forms clonal groups by long rhizomatous shoots. Tricoryne soullierae has a restricted distribution in remnant vegetation in the northern wheatbelt. It has fibrous roots and is conspicuously leafy when flowering.

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