The ecological mechanisms of Acetes blooms as a threat to the security of cooling systems in coastal nuclear power plants

Recently, there have been an increasing number of reports on the shutdown of coastal nuclear power plants because of outbreaks of marine organisms, such as jellyfish and fish. These organisms clog the pipes during an outbreak or when they accumulate near nuclear power plants in coastal regions. The safety of nuclear power plants is threatened by Acetes blooms. Thus, based on the physiology and ecology of Acetes, including the biology, auxology, feeding ecology, population dynamics, environmental suitability and effects of nuclear power plant thermal effluents, three hypotheses were proposed by previous studies to explain the ecological mechanisms of an Acetes bloom: (1) the wintering ground hypothesis, (2) the population dynamics hypothesis and (3) the ecosystem dynamics hypothesis. The main content and prevention measures used in previous studies were introduced and reviewed. Ecological protection combined with relevant environmental protection policies and laws in coastal areas are the long-term goals for the management of Acetes blooms.

Engineering Microbial Consortia towards Bioremediation

Bioremediation is a sustainable remediation technology as it utilizes microorganisms to convert hazardous compounds into their less toxic or non-toxic constituent elements. This technology has achieved some success in the past decades; however, factors involving microbial consortia, such as microbial assembly, functional interactions, and the role of member species, hinder its development. Microbial consortia may be engineered to reconfigure metabolic pathways and reprogram social interactions to get the desired function, thereby providing solutions to its inherent problems. The engineering of microbial consortia is commonly applied for the commercial production of biomolecules. However, in the field of bioremediation, the engineering of microbial consortia needs to be emphasized. In this review, we will discuss the molecular and ecological mechanisms of engineering microbial consortia with a particular focus on metabolic cross-feeding within species and the transfer of metabolites. We also discuss the advantages and limitations of top-down and bottom-up approaches of engineering microbial consortia and their applications in bioremediation.

Drivers and Determinants of Strain Dynamics Following Faecal Microbiota Transplantation

Faecal microbiota transplantation (FMT) is an efficacious therapeutic intervention, but its clinical mode of action and underlying microbiome dynamics remain poorly understood. Here, we analysed the metagenomes associated with 142 FMTs, in a time series-based meta-study across five disease indications. We quantified strain-level dynamics of 1,089 microbial species based on their pangenome, complemented with 47,548 newly constructed metagenome-assembled genomes. Using subsets of procedural-, host- and microbiome-based variables, LASSO-regularised regression models accurately predicted the colonisation and resilience of donor and recipient microbes, as well as turnover of individual species. Linking this to putative ecological mechanisms, we found these sets of variables to be informative of the underlying processes that shape the post-FMT gut microbiome. Recipient factors and complementarity of donor and recipient microbiomes, encompassing entire communities to individual strains, were the main determinants of individual strain population dynamics, and mostly independent of clinical outcomes. Recipient community state and the degree of residual strain depletion provided a neutral baseline for donor strain colonisation success, in addition to inhibitive priority effects between species and conspecific strains, as well as putatively adaptive processes. Our results suggest promising tunable parameters to enhance donor flora colonisation or recipient flora displacement in clinical practice, towards the development of more targeted and personalised therapies.

Particle foraging strategies promote microbial diversity in marine environments

Microbial foraging in patchy environments, where resources are fragmented into particles or pockets embedded in a large matrix, plays a key role in natural environments. In the oceans and freshwater systems, particle-associated bacteria can interact with particle surfaces in different ways: some colonize only during short transients, while others form long-lived, stable colonies. We do not yet understand the ecological mechanisms by which both short-term and long-term colonizers can coexist. Here, we address this problem with a mathematical model that explains how marine populations with different detachment rates from particles can stably coexist. In our model, populations grow only while on particles, but also face the increased risk of mortality by predation and sinking. Key to coexistence is the idea that detachment from particles modulates both net growth and mortality, but in opposite directions, creating a trade-off between them. While slow-detaching populations show the highest growth return (i.e., produce more net offspring), they are more susceptible to suffer higher rates of mortality than fast-detaching populations. Surprisingly, fluctuating environments, manifesting as blooms of particles (favoring growth) and predators (favoring mortality) significantly expand the likelihood that populations with different detachment rates can coexist. Our study shows how the spatial ecology of microbes in the ocean can lead to a predictable diversification of foraging strategies and the coexistence of multiple taxa on a single growth-limiting resource.

Resistance and Resilience of Fish Gut Microbiota to Silver Nanoparticles

Understanding the ecological mechanisms governing the resistance and resilience of microbial communities is a key issue to predict their responses to environmental disturbances. Using the zebrafish model, we wanted to clarify the potential mechanisms governing the resistance and resilience of gut microbiota after exposure to silver nanoparticles (AgNPs).

The physical-chemical characteristics of surface waters in the management of quality in clearwater rivers in the Brazilian Amazon

The study of water quality in the Amazon region is important for understanding the functioning of ecological mechanisms. The standard that governs water quality in Brazil, including the Amazon, is Resolution CONAMA 357/05, which uses criteria inspired by standards from other countries. However, this resolution does not consider characteristics of Amazonian aquatic ecosystems, and this can lead to incorrect interpretation of the data. Furthermore, there are few studies on the physical-chemical characteristics of clearwater rivers in the Amazon and the influence of the forest-water interface. Therefore, water samples were collected from four clearwater tributary watersheds of the Amazonas and Tapajós Rivers during the dry season in the city of Santarém, Pará. Most of the points were collected in pristine areas in order to capture the natural physicochemical characteristics of clearwater rivers, as well as to show the importance of ecoregional aspects in water quality management. All samples were below pH 6.0, which represents non-compliance with the CONAMA resolution. Statistical tests yielded negative correlations between pH and conductivity (r = −0.87, p < 0.05), Therefore, the rivers of lower ionic load are influenced by the type of surrounding vegetation, which are characteristics that have been widely reported for blackwater rivers.

Sex-Differentiated Attire’s Impact on Individual Action and Mate Selection

Various theories highlight the importance of using the actor/environment as the ideal unit for theoretical and experimental focus. Clothing, placed as it is as the intermediary between body and environment, is typically treated as a symbol rather than as either an integral part of either the body or the environment. When clothing is considered an extension of the body, the historical development of clothing reflects persistent differences in the physical capabilities of the human animal and operates as an instrument for solo action. In addition, it is argued that due to the ecological mechanisms connecting perception and action, differential clothing options for the sexes has led in no small part to differences in self-perception as well as the perception of others. However, when it comes to the very specific behavior of mate selection and procreation, clothing can be understood as a tether between two systemic units, offering a description of a system that allows for communication of potential social affordances and opportunities for joint action.

Diversity and evolution of amphibian pupil shapes

Pupil constriction has important functional consequences for animal vision, yet the evolutionary mechanisms underlying diverse pupil sizes and shapes, often among animals that occupy optically similar environments, are poorly understood. We aimed to quantify the diversity and evolution of pupil shapes among amphibians and test for potential correlations to ecology based on functional hypotheses. Using photographs, we surveyed pupil shape and the orientation of the constricted pupil across adults of 1293 amphibian species, 72 families, and 3 orders, and additionally for larval life stages for all families of frogs and salamanders with a biphasic ontogeny. Pupil shape is exceptionally diverse in amphibians with evolutionary transitions throughout the amphibian tree of life. For amphibians with a biphasic life history, we found that pupils change in many species that occupy distinct habitats before and after metamorphosis. Finally, we found that non-elongated (round or diamond) constricted pupils were correlated with species inhabiting consistently dim light environments (burrowing and aquatic species) and that elongated pupils (vertical and horizontal) were more common in species with larger absolute eye sizes. We propose that amphibians provide a valuable group within which to explore the anatomical, physiological, optical, and ecological mechanisms underlying the evolution of pupil shape.