Ecological characteristics of the composition of diatoms of benthic algocenoses in the mouth of the Oka River

Author(s):  
Khediaria Tabet

A brief description of the species composition, taxonomic structure and ecological indicators of diatoms on the right bank of the mouth section of a large eutrophic – hypertrophic river is given. The similarities and differences in taxonomic structure, a set of common and rare species of diatoms in different types of benthal communities with a more complex organization of the epilithon are shown. Satisfactory correspondence between the assessment of the composition of benthic Bacillariophyta and the physicochemical conditions of their habitat has been demonstrated.

2019 ◽  
Vol 16 ◽  
pp. 00002
Author(s):  
Ekaterina Antipova ◽  
Olga Enulenko

Sidinskiy and Pribaitakskiy steppes are the part of the Minusinsk province of the Altai-Sayan mountain country. On the territory of steppes 12 local floras (LF) were marked and examined using the same method. Studies were carried out according to the recommendations of A.I. Tolmachev (1931): identification of different types of ecotypes of LF, the full species composition of ecotypes (flora inventory), tracking the completeness of detection in LF. In the Sidinskiy steppe the number of families in the LF varies from 25 (Syida) to 43 (v. Alha), in the Pribaitakskiy steppe there is a big difference in the number of families in the LF from 31 (Krasnoyarsk reservoir, Tuba) to 65 (Mayak, Idra). The leading families in the local steppe flora are Asteraceae, Poaceae, Fabaceae. The Fabaceae family ranks third in the top of ten families in 50 % of LF, determining the type of flora as the Mediterranean-Central Asian (Fabaceae-type). Different types of LF allow to determine the type of all steppe flora as mixed, combining features of boreal (Asteraceae-Poaceae- type) and steppes flora (Fabaceae-type) with close ties with Central European floras (Rosaceae-type). 4 distinct levels of species richness are determined: 1 − 496-544; 2 − 408-413; 3 − 319-374; 4 − 279-298 species.


2019 ◽  
pp. 61-72
Author(s):  
T. V. Belich ◽  
S. Ye. Sadogurskiy ◽  
S. A. Sadogurskaya

The results of nomenclature-taxonomic revision of the flora marine macrophytes of the Kazantip Nature Reserve (KNR) are presented. Currently, with the new data the species composition includes 73 species and intraspecific taxon (IST) of macroalgae and sea grasses. Taxonomic structure of flora of the macrophytes of the KNR includes 4 phylums, 7 classes, 19 orders, 28 families, (F), 37 genera. Chlorophyta - 33 species, Ochrophyta - 11, Rhodophyta - 25, Tracheophyta - 4. In the flora prevail mesosaprobic (44%), annuae (58%), brackish-sea (51%), warm-water (40%) species. The category of rare fraction includes 14 species.


1994 ◽  
Vol 161 ◽  
pp. 385-400
Author(s):  
B.G. Marsden

Past surveys are described in the logical sequence of (1) comets visually, (2) asteroids visually, (3) asteroids photographically and (4) comets photographically. Plots show the evolution of asteroid surveys in terms of visual discovery magnitude and ecliptic latitude, and similarities and differences between surveys for the different types of body are discussed. The paper ends with a brief discussion of more recent discovery methods and some thoughts on the future.


Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 311
Author(s):  
Anna Granath Hansson ◽  
Peter Ekbäck ◽  
Jenny Paulsson

This paper aims to elucidate the sliding scale between usufruct and ownership by applying a property rights framework to three Swedish forms of tenure in multifamily housing. The framework deconstructs the bundles of rights of rental, tenant-ownership and ownership to highlight commonalities and differences connected to the right to use and exclude, the right to transfer and the right to the value. It is concluded that the three tenure forms have many traits in common but that there are distinct differences in some areas, most notably in connection to the right to the value. The property rights framework applied in the study may be applicable also on a general level as a method to analyze and compare tenures of different types in different countries. Further, ways to improve the framework and cover more facets of outcomes of property rights patterns are suggested.


Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 734
Author(s):  
Xuhua Xia

The design of Pfizer/BioNTech and Moderna mRNA vaccines involves many different types of optimizations. Proper optimization of vaccine mRNA can reduce dosage required for each injection leading to more efficient immunization programs. The mRNA components of the vaccine need to have a 5’-UTR to load ribosomes efficiently onto the mRNA for translation initiation, optimized codon usage for efficient translation elongation, and optimal stop codon for efficient translation termination. Both 5’-UTR and the downstream 3’-UTR should be optimized for mRNA stability. The replacement of uridine by N1-methylpseudourinine () complicates some of these optimization processes because is more versatile in wobbling than U. Different optimizations can conflict with each other, and compromises would need to be made. I highlight the similarities and differences between Pfizer/BioNTech and Moderna mRNA vaccines and discuss the advantage and disadvantage of each to facilitate future vaccine improvement. In particular, I point out a few optimizations in the design of the two mRNA vaccines that have not been performed properly.


2014 ◽  
Vol 96 (2) ◽  
Author(s):  
Dominik Perler

Abstract:According to Spinoza, there is no categorical distinction between human and non-human animals: they all belong to the same nature and all consist of bodies with corresponding ideas. This thesis gives rise to two problems. How is it possible to distinguish different types of animals, in particular nonrational and rational ones, if all of them have the same metaphysical structure? And why does Spinoza nevertheless claim that human beings have a privileged status that gives them the right to use non-rational animals? This paper examines these two problems, arguing that the solution to both of them lies in Spinoza’s all-embracing naturalism.


2016 ◽  
Vol 19 (3) ◽  
pp. 432-439
Author(s):  
Melville Saayman ◽  
Waldo Krugell ◽  
Andrea Saayman

The Cape Argus Pick n Pay Cycle Tour is a major event on the road cycling calendar. The majority of cyclists travel significant distances and participation produces a substantial carbon footprint. This paper examines participants’ willingness to pay to offset their carbon footprint. The purpose of this paper is to make a contribution to the literature by linking willingness to pay to attitudes towards or beliefs (green views) about the initiatives in place, to ensure a greener cycle tour. Factor analysis is used to identify different types of cyclists, based on their green views: those with green money, those who prefer green products and the “re-cyclers”. The results of the regression analysis reveal that socio-demographic variables and the right attitude towards the environment are significant predictors of stated willingness to pay for climate change mitigation.


2016 ◽  
Vol 1 (1S) ◽  
Author(s):  
Marta Wojewódka ◽  
Edyta Zawisza ◽  
Sergio Cohuo ◽  
Laura Macario-González ◽  
Antje Schwalb ◽  
...  

<p>Cladocera species composition was analyzed in surface sediments of 29 lakes in Central America (Guatemala, El Salvador and Honduras). The material studied was collected with an Ekman grab in autumn 2013 from lakes located in lowland, highland and mountain regions. The study revealed high variability in qualitative and quantitative composition of subfossil Cladocera. A total of 31 Cladocera species (5 planktonic and 26 littoral) were identified, as well as 4 morphotypes that could not be identified (NRR<em> </em>1-4). Planktonic Bosminidae<em> </em>and<em> </em>Daphniidae were the most abundant families. Daphniidae were restricted to water bodies in mountain regions, whereas Bosminidae were widely distributed in lakes with different abiotic conditions. Moreover, Bosminidae species also occurred in highly mineralized waters (&gt; 900 µS cm<sup>-1</sup>). The great majority of the identified Cladocera species belonged to the littoral family Chydoridae. <em>Chydorus </em>cf.<em> sphaericus</em> was the most common species (found in 20 lakes), which probably reflects its tolerance to a wide spectrum of habitat conditions. Cluster analysis discriminated 6 groups of Cladocera species with a high correlation level within groups (≥0.8), which showed different types of correlation with lake characteristics and environmental variables. Canonical correspondence analysis (CCA) showed that altitude and secondly water electrical conductivity were the most important drivers of Cladocera species composition in the region studied. Furthermore, CCA analysis indicated lowland lakes with low water transparency were also characterized by peculiar species assemblages. <strong></strong></p>


1987 ◽  
Vol 82 (1) ◽  
pp. 119-124 ◽  
Author(s):  
M. Dora Feliciangeli

A study on the ecology of phlebotomine sandfly fauna in a restricted focus of cutaneous leishmaniasis in northern Venezuela was undertaken in order to investigate the species responsible for the transmission. The study area and catching methods for phlebotomine sandflies are described. A total of 9,061 females and 1,662 males were collected during a year-term study. 12 species of Lutzomya and 1 species of Brumptomya sp. were identified. Absolute and relative abundance and ocurrence for each species were determined. The rel ative occurrence allowed to distinguish the common species, viz. L. panamensis, L. ovallesi, L. gomezi, L. tinidadensis, L. atroclavata, L. cayennensis, L. shannoni and L. olmeca bicolor from the rare species vis., L. punctigeniculata, L. rangeliana, L. evansi and L. dubitans. General comments on the species composition of the sandfly fauna in this locality are made.


2018 ◽  
Vol 25 (4) ◽  
pp. 3-7
Author(s):  
Piotr Tabor ◽  
Czesław Urbanik ◽  
Andrzej Mastalerz

Abstract Introduction. The aim of this study was to determine the correlations between the direction and velocity of the ball in volleyball spike. We adopted the hypothesis that the direction of an attack is dependent upon the arrangement of the pectoral girdles in the phase of flight. Material and methods. The research was carried out for four different types of attacks: from the left side of the court down the line (A) and in the cross-court direction (B) and from the right side in the same directions (C and D). Sixteen young volleyball players from a Sports Championship School run by the Polish Volleyball Federation were examined. Results. The analysis of the results showed different ball velocities in different attacks. The velocity was the lowest in attack B and the highest in attack D. Conclusions. The direction of attack was produced by hitting the ball in a non-central manner and by aligning the glenohumeral joints diagonally to the net.


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