Emergent Diversity and Persistent Turnover in Evolving Microbial Cross-Feeding Networks

A distinguishing feature of many ecological networks in the microbial realm is the diversity of substrates that could potentially serve as energy sources for microbial consumers. The microorganisms are themselves the agents of compound diversification via metabolite excretion or overflow metabolism. It has been suggested that the emerging richness of different substrates is an important condition for the immense biological diversity in microbial ecosystems. In this work, we study how complex cross-feeding networks (CFN) of microbial species may develop from a simple initial community given some elemental evolutionary mechanisms of resource-dependent speciation and extinctions using a network flow model. We report results of several numerical experiments and report an in-depth analysis of the evolutionary dynamics. We find that even in stable environments, the system is subject to persisting turnover, indicating an ongoing co-evolution. Further, we compare the impact of different parameters, such as the ratio of mineralization, as well as the metabolic versatility and variability on the evolving community structure. The results imply that high microbial and molecular diversity is an emergent property of evolution in cross-feeding networks, which affects transformation and accumulation of substrates in natural systems, such as soils and oceans, with potential relevance to biotechnological applications.

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ECOLOGICAL AND ECONOMIC JUSTIFICATION OF THE INVESTMENTS’ EFFICIENCY IN THE INTEGRATED DEVELOPMENT OF TERRITORIES

10.32008/geolinks2021/b2/v3/34 ◽

2021 ◽

Author(s):

Gennady Vladimirovich Olgarenko ◽

Valentin Nikolaevich Krasnoshchekov ◽

Denis Gennadievich Olgarenko

Keyword(s):

Economic Efficiency ◽

Biological Diversity ◽

Land Development ◽

The State ◽

Social Significance ◽

Integrated Development ◽

Natural Systems ◽

Scientific Organisation ◽

The Impact

"Intensive human economic activity has led to decrese in the natural resource potential of territories and qualitative changes in the natural environment surrounding a person: a violation of the spatial and functional structure of natural systems, a decrease in the biological diversity of flora and fauna, a deterioration in the quality of water and land resources, a decrease in the ecological and economic sustainability of technical and natural systems and the quality of human life. Ensuring the sustainable functioning and development of territories is possible due to the complex arrangement of the territory (scientific organisation of the territory). It is the optimisation of the land using structure that will restore disturbed ecosystems to standard values, increase biological diversity, environmental sustainability and economic efficiency of landscapes. One of the limiting factors in the implementation of this measure is the lack of an effective mechanism for assessing the effectiveness of investments in land development. All this indicates the need to develop proposals for the development of methodological approaches to assessing the environmental and economic efficiency of investments in land development, taking into account the shortcomings that we identified when analyzing existing approaches to assessing the effectiveness of investment projects of social significance. At the same time, it should be noted that ensuring sustainable development of territories is impossible with the existing nature-intensive concept of economic development. A new approach to solving this problem is needed, which should: • be based on a deep study of socio-economic and environmental problems, a retrospective analysis of the state of landscapes and a long-term forecast of the expected consequences of the impact of human activity on the state of individual components of the considered territory and the landscape as a whole; • it aims to ensure the socio-economic and environmental safety of Russia. The рurpose is to develop proposals for the development of a methodological approach to assessing the environmental and economic efficiency of investments in the integrated development of territories which are aimed at ensuring the socio-economic and environmental security of Russia."

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Whole-Genome Analyses Identifies Multiple Reassortant Rotavirus Strains in Rwanda Post-Vaccine Introduction

Viruses ◽

10.3390/v13010095 ◽

2021 ◽

Vol 13 (1) ◽

pp. 95

Author(s):

Sebotsana Rasebotsa ◽

Jeannine Uwimana ◽

Milton T. Mogotsi ◽

Kebareng Rakau ◽

Nonkululeko B. Magagula ◽

...

Keyword(s):

Amino Acid ◽

Genome Analysis ◽

Evolutionary Dynamics ◽

Developed Countries ◽

Whole Genome ◽

Whole Genome Analysis ◽

Evolutionary Mechanisms ◽

Vaccine Introduction ◽

Rotavirus Vaccines ◽

The Impact

Children in low-and middle-income countries, including Rwanda, experience a greater burden of rotavirus disease relative to developed countries. Evolutionary mechanisms leading to multiple reassortant rotavirus strains have been documented over time which influence the diversity and evolutionary dynamics of novel rotaviruses. Comprehensive rotavirus whole-genome analysis was conducted on 158 rotavirus group A (RVA) samples collected pre- and post-vaccine introduction in children less than five years in Rwanda. Of these RVA positive samples, five strains with the genotype constellations G4P[4]-I1-R2-C2-M2-A2-N2-T1-E1-H2 (n = 1), G9P[4]-I1-R2-C2-M2-A1-N1-T1-E1-H1 (n = 1), G12P[8]-I1-R2-C2-M1-A1-N2-T1-E2-H3 (n = 2) and G12P[8]-I1-R1-C1-M1-A2-N2-T2-E1-H1 (n = 1), with double and triple gene reassortant rotavirus strains were identified. Phylogenetic analysis revealed a close relationship between the Rwandan strains and cognate human RVA strains as well as the RotaTeq® vaccine strains in the VP1, VP2, NSP2, NSP4 and NSP5 gene segments. Pairwise analyses revealed multiple differences in amino acid residues of the VP7 and VP4 antigenic regions of the RotaTeq® vaccine strain and representative Rwandan study strains. Although the impact of such amino acid changes on the effectiveness of rotavirus vaccines has not been fully explored, this analysis underlines the potential of rotavirus whole-genome analysis by enhancing knowledge and understanding of intergenogroup reassortant strains circulating in Rwanda post vaccine introduction.

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The Catholic Diaspora—Experiences of Evacuation

10.1093/oso/9780198827023.003.0005 ◽

2018 ◽

Author(s):

Thomas Brodie

Keyword(s):

Urban Areas ◽

Religious Practice ◽

Catholic Clergy ◽

Profound Influence ◽

The Social ◽

Depth Analysis ◽

Nazi Era ◽

Mass Evacuation ◽

The Impact ◽

Pastoral Practice

This chapter analyses the impact exerted on the Catholic Church’s pastoral networks in Germany by the mass evacuation of laypeople from bombed urban areas as of 1941. Drawing on the voluminous correspondence of priests and curates despatched from the Rhineland and Westphalia to Saxony, Thuringia, Silesia, Austria, and elsewhere to minister to Catholic evacuees, this chapter provides in-depth analysis of the social and cultural histories of religious practice in wartime Germany. It demonstrates that the evacuation of laypeople—a topic long neglected within histories of wartime religious practice—exerted a profound influence on pastoral practice by the years 1943–5, placing unprecedented pressures on the Catholic clergy of the dioceses central to this study (Aachen, Cologne and Münster). This chapter therefore also casts new light on regionalism in Germany during the Nazi era.

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Decreased Medical Care During the COVID-19 Pandemic – A Comprehensive Analysis of Radiological Examinations

RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren ◽

10.1055/a-1368-5047 ◽

2021 ◽

Author(s):

Annette Aigner ◽

Bernd Hamm ◽

Florian Nima Fleckenstein ◽

Tazio Maleitzke ◽

Georg Böning ◽

...

Keyword(s):

Medical Care ◽

Control Period ◽

Surrogate Marker ◽

Medical Specialty ◽

Case Volume ◽

Medical Specialties ◽

Key Points ◽

Depth Analysis ◽

The Impact ◽

Radiological Examinations

Objectives As a cross-section discipline within the hospital infrastructure, radiological departments might be able to provide important information regarding the impact of the COVID-19 pandemic on healthcare. The goal of this study was to quantify changes in medical care during the first wave of the pandemic using radiological examinations as a comprehensive surrogate marker and to determine potential future workload. Methods A retrospective analysis of all radiological examinations during the first wave of the pandemic was performed. The number of examinations was compared to time-matched control periods. Furthermore, an in-depth analysis of radiological examinations attributed to various medical specialties was conducted and postponed examinations were extrapolated to calculate additional workload in the near future. Results A total of 596,760 examinations were analyzed. Overall case volumes decreased by an average of 41 % during the shutdown compared to the control period. The most affected radiological modalities were sonography (–54 %), X-ray (–47 %) followed by MRI (–42 %). The most affected medical specialty was trauma and orthopedics (–60 % case volume) followed by general surgery (–49 %). Examination numbers increased during the post-shutdown period leading to a predicted additional workload of up to 22 %. Conclusion This study shows a marked decrease in radiological examinations in total and among several core medical specialties, indicating a significant reduction in medical care during the first COVID-19 shutdown. Key Points: Citation Format

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Ontogenetic shift in the trophic role of the invasive killer shrimp Dikerogammarus villosus: a stable isotope study

Biological Invasions ◽

10.1007/s10530-021-02472-0 ◽

2021 ◽

Author(s):

Francesco Mancini ◽

Raffaele De Giorgi ◽

Alessandro Ludovisi ◽

Salvatrice Vizzini ◽

Giorgio Mancinelli

Keyword(s):

Dietary Habits ◽

Trophic Position ◽

Ecological Impact ◽

Central Italy ◽

Local Conditions ◽

Dikerogammarus Villosus ◽

Isotopic Signatures ◽

Depth Analysis ◽

Stable Isotope Study ◽

The Impact

AbstractThe introduction of the amphipod Dikerogammarus villosus in European fresh waters is to date recognized as a threat to the integrity of invaded communities. Predation by D. villosus on native benthic invertebrates is assumed as the key determinant of its ecological impact, yet available information describe the species as a primary consumer as well as a carnivore depending on local conditions. Here, we assessed the trophic position (TP) of D. villosus in Lake Trasimeno, a recently invaded lentic system in central Italy, using the CN isotopic signatures of individuals captured in winter spanning two orders of magnitude in body size. TP estimations were compared with those characterizing the native amphipod Echinogammarus veneris and other representative invertebrate predators. On average, D. villosus showed a trophic position higher than E. veneris, and comparable with that of odonate nymphs. An in-depth analysis revealed that large-sized individuals had a trophic position of 3.07, higher than odonates and close to that of the hirudinean predator Erpobdella octoculata, while small-sized specimens had a trophic position of 2.57, similar to that of E. veneris (2.41). These findings indicate that size-related ontogenetic shifts in dietary habits may per se vary the nature of the interaction between Dikerogammarus villosus and native invertebrates from competition to predation. Information collated from published isotopic studies corroborated the generality of our results. We conclude that intra-specific trophic flexibility may potentially amplify and make more multifaceted the impact of the species on other invertebrate species in invaded food webs.

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Corporate Social Responsibility Disclosure: Responding to Investors’ Criticism on Social Media

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18147396 ◽

2021 ◽

Vol 18 (14) ◽

pp. 7396

Author(s):

Yuming Zhang ◽

Fan Yang

Keyword(s):

Social Media ◽

Corporate Social Responsibility ◽

Social Responsibility ◽

Social Issues ◽

Media Criticism ◽

Csr Communication ◽

Depth Analysis ◽

Csr Disclosure ◽

Corporate Social ◽

The Impact

Companies use corporate social responsibility (CSR) disclosures to communicate their social and environmental policies, practices, and performance to stakeholders. Although the determinants and outcomes of CSR activities are well understood, we know little about how companies use CSR communication to manage a crisis. The few relevant CSR studies have focused on the pressure on corporations exerted by governments, customers, the media, or the public. Although investors have a significant influence on firm value, this stakeholder group has been neglected in research on CSR disclosure. Grounded in legitimacy theory and agency theory, this study uses a sample of Chinese public companies listed on the Shanghai Stock Exchange to investigate CSR disclosure in response to social media criticism posted by investors. The empirical findings show that investors’ social media criticism not only motivates companies to disclose their CSR activities but also increases the substantiveness of their CSR reports, demonstrating that companies’ CSR communication in response to a crisis is substantive rather than merely symbolic. We also find that the impact of social media criticism on CSR disclosure is heterogeneous. Non-state-owned enterprises, companies in regions with high levels of environmental regulations, and companies in regions with local government concern about social issues are most likely to disclose CSR information and report substantive CSR activities. We provide an in-depth analysis of corporate CSR strategies for crisis management and show that crises initiated by investors on social media provide opportunities for corporations to improve their CSR engagement.

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The importance of species interactions in eco-evolutionary community dynamics under climate change

Nature Communications ◽

10.1038/s41467-021-24977-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Anna Åkesson ◽

Alva Curtsdotter ◽

Anna Eklöf ◽

Bo Ebenman ◽

Jon Norberg ◽

...

Keyword(s):

Climate Change ◽

Species Interactions ◽

Community Dynamics ◽

Evolutionary Dynamics ◽

Negative Impact ◽

Trophic Levels ◽

Temperature Dependent ◽

Modeling Framework ◽

Impact Of Climate Change ◽

The Impact

AbstractEco-evolutionary dynamics are essential in shaping the biological response of communities to ongoing climate change. Here we develop a spatially explicit eco-evolutionary framework which features more detailed species interactions, integrating evolution and dispersal. We include species interactions within and between trophic levels, and additionally, we incorporate the feature that species’ interspecific competition might change due to increasing temperatures and affect the impact of climate change on ecological communities. Our modeling framework captures previously reported ecological responses to climate change, and also reveals two key results. First, interactions between trophic levels as well as temperature-dependent competition within a trophic level mitigate the negative impact of climate change on biodiversity, emphasizing the importance of understanding biotic interactions in shaping climate change impact. Second, our trait-based perspective reveals a strong positive relationship between the within-community variation in preferred temperatures and the capacity to respond to climate change. Temperature-dependent competition consistently results both in higher trait variation and more responsive communities to altered climatic conditions. Our study demonstrates the importance of species interactions in an eco-evolutionary setting, further expanding our knowledge of the interplay between ecological and evolutionary processes.

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Synchronization in 5G networks: a hybrid Bayesian approach toward clock offset/skew estimation and its impact on localization

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01963-x ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Meysam Goodarzi ◽

Darko Cvetkovski ◽

Nebojsa Maletic ◽

Jesús Gutiérrez ◽

Eckhard Grass

Keyword(s):

Bayesian Approach ◽

Large Scale ◽

Hybrid Approach ◽

Position Estimation ◽

5G Networks ◽

Clock Skew ◽

Depth Analysis ◽

The Impact ◽

Mean Square Errors ◽

Clock Offset

AbstractClock synchronization has always been a major challenge when designing wireless networks. This work focuses on tackling the time synchronization problem in 5G networks by adopting a hybrid Bayesian approach for clock offset and skew estimation. Furthermore, we provide an in-depth analysis of the impact of the proposed approach on a synchronization-sensitive service, i.e., localization. Specifically, we expose the substantial benefit of belief propagation (BP) running on factor graphs (FGs) in achieving precise network-wide synchronization. Moreover, we take advantage of Bayesian recursive filtering (BRF) to mitigate the time-stamping error in pairwise synchronization. Finally, we reveal the merit of hybrid synchronization by dividing a large-scale network into local synchronization domains and applying the most suitable synchronization algorithm (BP- or BRF-based) on each domain. The performance of the hybrid approach is then evaluated in terms of the root mean square errors (RMSEs) of the clock offset, clock skew, and the position estimation. According to the simulations, in spite of the simplifications in the hybrid approach, RMSEs of clock offset, clock skew, and position estimation remain below 10 ns, 1 ppm, and 1.5 m, respectively.

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Speciation and changes in male gene expression in Drosophila

Genome ◽

10.1139/gen-2020-0025 ◽

2020 ◽

pp. 1-11

Author(s):

Bahar Patlar ◽

Alberto Civetta

Keyword(s):

Gene Expression ◽

Reproductive Isolation ◽

Potential Role ◽

Regulation Of Gene Expression ◽

Drosophila Model ◽

Depth Analysis ◽

The Impact ◽

Plastic Responses ◽

Male Gene

It has long been acknowledged that changes in the regulation of gene expression may account for major organismal differences. However, we still do not fully understand how changes in gene expression evolve and how do such changes influence organisms’ differences. We are even less aware of the impact such changes might have in restricting gene flow between species. Here, we focus on studies of gene expression and speciation in the Drosophila model. We review studies that have identified gene interactions in post-mating reproductive isolation and speciation, particularly those that modulate male gene expression. We also address studies that have experimentally manipulated changes in gene expression to test their effect in post-mating reproductive isolation. We highlight the need for a more in-depth analysis of the role of selection causing disrupted gene expression of such candidate genes in sterile/inviable hybrids. Moreover, we discuss the relevance to incorporate more routinely assays that simultaneously evaluate the potential effects of environmental factors and genetic background in modulating plastic responses in male genes and their potential role in speciation.

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Ranking the critical sections of railway networks

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409720925689 ◽

2020 ◽

pp. 095440972092568

Author(s):

Ratthaphong Meesit ◽

John Andrews

Keyword(s):

Network Flow ◽

Topological Analysis ◽

Preventive Strategy ◽

Railway Network ◽

Macroscopic Models ◽

Railway Systems ◽

Railway Networks ◽

Network Simulation Model ◽

The Impact ◽

Critical Sections

Railway systems are now facing an increasing number of threats such as aging infrastructures and climate changes. The identification of critical network sections provides infrastructure managers with the ability to understand the impact of a disruption and creates a suitable preventive strategy to counter such threats. To this end, various vulnerability analysis methods have been proposed for railway networks. Two main types of methods, network topological analysis and network flow-based analysis, have been developed. Both approaches are constructed based on macroscopic models, which take only some railway properties such as network structure, train and passenger flow into account. Thus, the results obtained are high level approximations. This study proposes a new analysis method, which is developed based on the stochastic-microscopic railway network simulation model. The method can be applied to identify the critical sections of a railway network. The effect of impact levels and occurrence times of a disruption on the network section criticality is presented. An application of the proposed model is demonstrated using the Liverpool railway network in the UK.

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