A clustering strategy based on a formalism of the reproductive process in natural systems

Author(s):  
Vijay V. Raghavan ◽  
Kim Birchard
Author(s):  
L. P. Hardie ◽  
D. L. Balkwill ◽  
S. E. Stevens

Agmenellum quadruplicatum is a unicellular, non-nitrogen-fixing, marine cyanobacterium (blue-green alga). The ultrastructure of this organism, when grown in the laboratory with all necessary nutrients, has been characterized thoroughly. In contrast, little is known of its ultrastructure in the specific nutrient-limiting conditions typical of its natural habitat. Iron is one of the nutrients likely to limit this organism in such natural environments. It is also of great importance metabolically, being required for both photosynthesis and assimilation of nitrate. The purpose of this study was to assess the effects (if any) of iron limitation on the ultrastructure of A. quadruplicatum. It was part of a broader endeavor to elucidate the ultrastructure of cyanobacteria in natural systemsActively growing cells were placed in a growth medium containing 1% of its usual iron. The cultures were then sampled periodically for 10 days and prepared for thin sectioning TEM to assess the effects of iron limitation.


2011 ◽  
Vol 6 (2) ◽  
Author(s):  
M. Nils Peterson ◽  
Hans Peter Hansen ◽  
Markus J Peterson ◽  
Tarla R. Peterson

2020 ◽  
Vol 19 (10) ◽  
pp. 1896-1915
Author(s):  
E.R. Ermakova ◽  
O.M. Lizina

Subject. The article addresses the specifics of shadow economic activities in reformed Russia in the context of systemic transformations. Objectives. We focus on determining the role of shadow economy in the reproductive process, identifying and understanding the specifics of underground economic activity of the Russian economy. Methods. The study rests on general scientific methods (scientific abstraction, unity of historical and logical, analysis and synthesis, induction and deduction, comparison and analogy) and special methods of cognition (monetary methods). We employ the systems and integrated approach. The official statistics, regulations, works of leading researchers on shadow economy expansion, resources of reference and legal systems like Garant and ConsultantPlus serve as the study's information base. Results. We present a retrospective rapid analysis of the extent of shadow economic activity in the domestic economy, establishing the relationships with the processes that take place at different stages of the country's development. We also reveal the specifics of shadow economy relations in Russia, factors that play a key role in expansion for a particular period, a shift to another form of shadow economy. The study characterizes the current period of development, assesses the impact of external shocks on shadow economy expansion. Conclusions. The current period is characterized by the digitization of shadow relations, the shift of corruption to the upper echelons of power, the continued outflow of capital abroad, and increased penalties for underground activities.


2019 ◽  
Vol 41 (4) ◽  
pp. 398-409
Author(s):  
Lidiya Senkova ◽  
Anastasia Kiseleva ◽  
Valeriya Tskhovrebov
Keyword(s):  

2020 ◽  
Vol 42 (3) ◽  
pp. 293-303
Author(s):  
VALERIY BONDAREV

The theoretical and methodological basis of the systems hierarchical spatial and temporal analysis of a drainage basin, which addresses the problems of effective management in socio-natural systems of different ranks, is considered. It is proposed to distinguish 9 orders of forms that are relevant to the analysis of drainage basins, where the first level is represented by individual aggregates and particles, and the last - by basins of large and the largest rivers. As part of the allocation of geological, historical and modern time intervals, the specificity of the implementation of processes in basins of different scales from changing states, through functioning to evolution is demonstrated. The interrelation of conditions and factors that determine the processes occurring within the drainage basins is revealed. It is shown that a specific combination of conditions and factors that determine processes in the drainage basin is associated with the hierarchy of the objects under consideration, i.e. the choice of a spatial-temporal hierarchical level is crucial for the organization of study within drainage basins. At one hierarchical level, some phenomenon can be considered as a factor, and at another - as a condition. For example, tectonic processes can be considered as an active factor in the evolution of large river basins in the geological perspective, but for small drainage basin, this is already a conservative background condition. It is shown that at the historical time the anthropogenic factor often comes to the fore, with the appearance of which in the functioning of the drainage basin, there is a need to take into account the entire complex of socio-environmental problems that can affect the sustainable state of various territories, especially in the field of water and land use. Hierarchical levels of managing subjects are identified, which are primarily responsible for effective management at the appropriate hierarchical level of the organization of the socio-natural system within the catchment area, starting from an individual to humankind as a whole.


1999 ◽  
Vol 40 (11-12) ◽  
pp. 21-24
Author(s):  
Tapio Pento

Industrial ecology (IE) is a biological concept applied to industrial structures. The basic concepts of IE include regional, intra-firm and product-based waste recycling systems as well as the principle of upward and downward cascading. In best current examples of regional systems, several parties are in an industrial waste re-use symbiosis. Paper industry has learned to arrange the recovery and re-use of its products on distant markets, even up to a level where indications of exceeding optimal recovery and re-use rates already exist through deteriorated fibre and product quality. Such occurrences will take place in certain legislative-economic situations. Paper industry has many cascade levels, each with their internal recovery and recycling, as well as many intra-firm, regional, and life cycle ecology structures. As an example of prospects for individual cascading routes, sludges may continue to be incinerated, but the route to landfills will be closed. The main obstacles of legislative drive toward better IE systems are in many cases existing laws and political considerations rather than economic or technical aspects. The study and practice of engineering human technology systems and related elements of natural systems should develop in such a way that they provide quality of life by actively managing the dynamics of relevant systems to reduce the risk and scale of undesirable behavior and outcomes. For the paper industry, earth systems engineering offers several development routes. One of them is the further recognition of and research on the fact that the products of the industry are returned back to the carbon cycle of the natural environment. Opportunities for modifying current earth systems may also be available for the industry, e.g. genetically modified plants for raw materials or organisms for making good quality pulp out of current raw materials. It is to be recognized that earth systems engineering may become a very controversial area, and that very diverse political pressures may determine its future usefulness to the paper industry.


2019 ◽  
Vol 947 (5) ◽  
pp. 54-62
Author(s):  
M.D. Bogdanova ◽  
M.I. Gerasimova ◽  
V.A. Snytko

Professor Maria Glazovskaya (1912–2016) – an outstanding geographer, geochemist and soil scientist, made a prominent contribution to the formation and development of several aspects of thematic mapping both in conceptual and methodological issues. These aspects, namely, soil, landscape- and soil-geochemical, as well as ecological mapping, were derived from the knowledge on soils combined with the concepts of geochemical migrations facilities for certain chemical elements in soils and landscapes. Methodology of compilation of such maps presumes purposeful interpretation of diverse soil and landscape features, their expert evaluation and forecast of response reactions of soils and landscapes to certain technogenic loads. Maria Glazovskaya proposed innovative approaches to thematic mapping enabling her to compile original maps. She introduced the principle of “prognostic information capacity of natural factors”, which means that properties of landscape components contain information appropriate for evaluating the resilience of natural systems. The ideas and methods proposed by Maria Glazovskaya are now implemented in basic and applied thematic mapping.


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