Microbial Systems Ecology to Understand Cross-Feeding in Microbiomes

Understanding how microorganism-microorganism interactions shape microbial assemblages is a key to deciphering the evolution of dependencies and co-existence in complex microbiomes. Metabolic dependencies in cross-feeding exist in microbial communities and can at least partially determine microbial community composition. To parry the complexity and experimental limitations caused by the large number of possible interactions, new concepts from systems biology aim to decipher how the components of a system interact with each other. The idea that cross-feeding does impact microbiome assemblages has developed both theoretically and empirically, following a systems biology framework applied to microbial communities, formalized as microbial systems ecology (MSE) and relying on integrated-omics data. This framework merges cellular and community scales and offers new avenues to untangle microbial coexistence primarily by metabolic modeling, one of the main approaches used for mechanistic studies. In this mini-review, we first give a concise explanation of microbial cross-feeding. We then discuss how MSE can enable progress in microbial research. Finally, we provide an overview of a MSE framework mostly based on genome-scale metabolic-network reconstruction that combines top-down and bottom-up approaches to assess the molecular mechanisms of deterministic processes of microbial community assembly that is particularly suitable for use in synthetic biology and microbiome engineering.

Cybernetics and Technology of Development. Basic Definitions

Cybernetic research on the management of systems development is at an early stage: there are no examples of productive management of development of the state, economy, enterprise, technical systems, ecology, society, education, morality, health, intelligence, personality, psyche. For modern cybernetics, these challenges are a major challenge that it can meet only after rethinking its fundamentals. The development process has the highest cost of decision-making error, because it is strategic, and to base development on the basis of dubious statements is not rational. A necessary foundation of development management methodology should be a self-evident statement that does not require any additional justification and that no one can question, and the whole system of basic concepts should be defined based on this statement. This article is devoted to solving this problem.

Ecosystem-Based Fisheries Management

By examining a suite of over 90 indicators for nine major U.S. fishery ecosystem jurisdictions, Link and Marshak systematically track the progress the U.S. has made toward advancing ecosystem-based fisheries management (EBFM) and making it an operational reality. Covering a range of socioeconomic, governance, environmental forcing, major pressures, systems ecology, and fisheries criteria, they evaluate progress toward EBFM in the U.S., covering a wide range of longitude, latitude, and parts of major ocean basins, representing over 10% of the world’s ocean surface area. They view progress toward the implementation of EBFM as synonymous with improved management of living marine resources in general, and highlight lessons learned from a national perspective. Although US-centric, the lessons learned are applicable for all parts of the global ocean. Though much work remains, significant progress has been made to better address many of the challenges facing the sustainable management of our living marine resources.

Cycles and circulation: a theme in the history of biology and medicine

We invite systematic consideration of the metaphors of cycles and circulation as a long-term theme in the history of the life and environmental sciences and medicine. Ubiquitous in ancient religious and philosophical traditions, especially in representing the seasons and the motions of celestial bodies, circles once symbolized perfection. Over the centuries cyclic images in western medicine, natural philosophy, natural history and eventually biology gained independence from cosmology and theology and came to depend less on strictly circular forms. As potent ‘canonical icons’, cycles also interacted with representations of linear and irreversible change, including arrows, arcs, scales, series and trees, as in theories of the Earth and of evolution. In modern times life cycles and reproductive cycles have often been held to characterize life, in some cases especially female life, while human efforts selectively to foster and disrupt these cycles have harnessed their productivity in medicine and agriculture. But strong cyclic metaphors have continued to link physiology and climatology, medicine and economics, and biology and manufacturing, notably through the relations between land, food and population. From the grand nineteenth-century transformations of matter to systems ecology, the circulation of molecules through organic and inorganic compartments has posed the problem of maintaining identity in the face of flux and highlights the seductive ability of cyclic schemes to imply closure where no original state was in fact restored. More concerted attention to cycles and circulation will enrich analyses of the power of metaphors to naturalize understandings of life and their shaping by practical interests and political imaginations.