The Pathogenicity ofShewanella algaeand Ability to Tolerate a Wide Range of Temperatures and Salinities

Shewanella algaeis a rod-shaped Gram-negative marine bacterium frequently found in nonhuman sources such as aquatic ecosystems and has been shown to be the pathogenic agent in various clinical cases due to the ingestion of raw seafood. The results of this study showed thatS. algaewas present in approximately one in four samples, including water and shellfish samples. Positive reactions (API systems) inS. algaestrains were seen for gelatinase (gelatin); however, negative reactions were found for indole production (tryptophan).S. algaeis adapted to a wide range of temperatures (4°C, 25°C, 37°C, and 42°C) and salinity. Temperature is a key parameter in the pathogenicity ofS. algaeas it appears to induce hemolysis at 25°C and 37°C.S. algaeexhibits pathogenic characteristics at widely varying temperatures, which suggests that it may have the ability to adapt to climate change.

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Multiyear variations in High Arctic river temperatures in response to climate variability

Arctic Science ◽

10.1139/as-2017-0053 ◽

2018 ◽

Vol 4 (4) ◽

pp. 605-623 ◽

Cited By ~ 1

Author(s):

Christopher Bolduc ◽

Scott F. Lamoureux

Keyword(s):

Climate Change ◽

Climate Variability ◽

Aquatic Ecosystems ◽

Ecosystem Health ◽

Cold Water ◽

Thermal Conditions ◽

River System ◽

High Arctic ◽

Small Rivers ◽

Wide Range

Water temperature measurements (2004–2016) from two small rivers in the High Arctic were analyzed to determine the effects of climate variability on thermal regime and the sensitivity to climate change. The East and West rivers (unofficial names) drain similar watersheds (11.6 and 8.0 km2, respectively) and are located at the Cape Bounty Arctic Watershed Observatory (CBAWO), Melville Island, Canada (74°55′N, 109°35′W). Differences in seasonal timing of river temperatures were evident when comparing the coldest and warmest years of the study period, and across different discharge conditions. Snowmelt runoff is characterized by uniformly cold water (∼0–1 °C) over a wide range of discharge conditions, followed by warming water temperatures during flow recession. The rivers showed varying sensitivity to mid-summer air temperature conditions in a given year, with warmer years indicating high correlation (r2 = 0.794–0.929), whereas colder years showed reduced correlation (r2 = 0.368–0.778). River temperatures reached levels which are reported to negatively affect fish and other cold-water aquatic species (>18 °C) with greater frequency and duration during the warmest years. These results provide a basis to further enhance prediction of river thermal conditions to assess ecosystem health in a river system and to refine insights into the effects of climate change on High Arctic aquatic ecosystems.

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A MODELING SYSTEM FOR CLIMATE CHANGE RISK ASSESSMENT, MANAGEMENT AND HEDGING IN COASTAL AREAS

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b9398d1adf1.08545898 ◽

2017 ◽

Author(s):

Sergei Soldatenko ◽

Genrikh Alekseev ◽

Alexander Danilov ◽

...

Keyword(s):

Climate Change ◽

Risk Assessment ◽

Coastal Areas ◽

Mitigation Strategies ◽

System Structure ◽

The Arctic ◽

Risk Modeling ◽

Wide Range ◽

Adverse Weather ◽

The Impact

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.

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The Biology of Mediterranean-Type Ecosystems

10.1093/oso/9780198739135.001.0001 ◽

2018 ◽

Cited By ~ 7

Author(s):

Karen J. Esler ◽

Anna L. Jacobsen ◽

R. Brandon Pratt

Keyword(s):

Climate Change ◽

South Africa ◽

Invasive Species ◽

Habitat Loss ◽

Endemic Species ◽

Geographic Area ◽

Cutting Edge ◽

Wide Range ◽

The Mediterranean ◽

Mediterranean Type Ecosystems

The world’s mediterranean-type climate regions (including areas within the Mediterranean, South Africa, Australia, California, and Chile) have long been of interest to biologists by virtue of their extraordinary biodiversity and the appearance of evolutionary convergence between these disparate regions. Comparisons between mediterranean-type climate regions have provided important insights into questions at the cutting edge of ecological, ecophysiological and evolutionary research. These regions, dominated by evergreen shrubland communities, contain many rare and endemic species. Their mild climate makes them appealing places to live and visit and this has resulted in numerous threats to the species and communities that occupy them. Threats include a wide range of factors such as habitat loss due to development and agriculture, disturbance, invasive species, and climate change. As a result, they continue to attract far more attention than their limited geographic area might suggest. This book provides a concise but comprehensive introduction to mediterranean-type ecosystems. As with other books in the Biology of Habitats Series, the emphasis in this book is on the organisms that dominate these regions although their management, conservation, and restoration are also considered.

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Stomatal conductance limited the CO2 response of grassland in the last century

BMC Biology ◽

10.1186/s12915-021-00988-4 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Juan C. Baca Cabrera ◽

Regina T. Hirl ◽

Rudi Schäufele ◽

Andy Macdonald ◽

Hans Schnyder

Keyword(s):

Climate Change ◽

Stomatal Conductance ◽

Nitrogen Nutrition ◽

Physiological Control ◽

Co2 Response ◽

Nitrogen Acquisition ◽

Wide Range ◽

Park Grass Experiment ◽

Conductance Changes ◽

Canopy Stomatal Conductance

Abstract Background The anthropogenic increase of atmospheric CO2 concentration (ca) is impacting carbon (C), water, and nitrogen (N) cycles in grassland and other terrestrial biomes. Plant canopy stomatal conductance is a key player in these coupled cycles: it is a physiological control of vegetation water use efficiency (the ratio of C gain by photosynthesis to water loss by transpiration), and it responds to photosynthetic activity, which is influenced by vegetation N status. It is unknown if the ca-increase and climate change over the last century have already affected canopy stomatal conductance and its links with C and N processes in grassland. Results Here, we assessed two independent proxies of (growing season-integrating canopy-scale) stomatal conductance changes over the last century: trends of δ18O in cellulose (δ18Ocellulose) in archived herbage from a wide range of grassland communities on the Park Grass Experiment at Rothamsted (U.K.) and changes of the ratio of yields to the CO2 concentration gradient between the atmosphere and the leaf internal gas space (ca – ci). The two proxies correlated closely (R2 = 0.70), in agreement with the hypothesis. In addition, the sensitivity of δ18Ocellulose changes to estimated stomatal conductance changes agreed broadly with published sensitivities across a range of contemporary field and controlled environment studies, further supporting the utility of δ18Ocellulose changes for historical reconstruction of stomatal conductance changes at Park Grass. Trends of δ18Ocellulose differed strongly between plots and indicated much greater reductions of stomatal conductance in grass-rich than dicot-rich communities. Reductions of stomatal conductance were connected with reductions of yield trends, nitrogen acquisition, and nitrogen nutrition index. Although all plots were nitrogen-limited or phosphorus- and nitrogen-co-limited to different degrees, long-term reductions of stomatal conductance were largely independent of fertilizer regimes and soil pH, except for nitrogen fertilizer supply which promoted the abundance of grasses. Conclusions Our data indicate that some types of temperate grassland may have attained saturation of C sink activity more than one century ago. Increasing N fertilizer supply may not be an effective climate change mitigation strategy in many grasslands, as it promotes the expansion of grasses at the disadvantage of the more CO2 responsive forbs and N-fixing legumes.

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Incorrect Asian aerosols affecting the attribution and projection of regional climate change in CMIP6 models

npj Climate and Atmospheric Science ◽

10.1038/s41612-020-00159-2 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Zhili Wang ◽

Lei Lin ◽

Yangyang Xu ◽

Huizheng Che ◽

Xiaoye Zhang ◽

...

Keyword(s):

Climate Change ◽

Radiative Forcing ◽

Impact Analysis ◽

Climate Model ◽

Regional Climate ◽

Eastern China ◽

Coupled Model ◽

Regional Climate Change ◽

Anthropogenic Aerosol ◽

Wide Range

AbstractAnthropogenic aerosol (AA) forcing has been shown as a critical driver of climate change over Asia since the mid-20th century. Here we show that almost all Coupled Model Intercomparison Project Phase 6 (CMIP6) models fail to capture the observed dipole pattern of aerosol optical depth (AOD) trends over Asia during 2006–2014, last decade of CMIP6 historical simulation, due to an opposite trend over eastern China compared with observations. The incorrect AOD trend over China is attributed to problematic AA emissions adopted by CMIP6. There are obvious differences in simulated regional aerosol radiative forcing and temperature responses over Asia when using two different emissions inventories (one adopted by CMIP6; the other from Peking university, a more trustworthy inventory) to driving a global aerosol-climate model separately. We further show that some widely adopted CMIP6 pathways (after 2015) also significantly underestimate the more recent decline in AA emissions over China. These flaws may bring about errors to the CMIP6-based regional climate attribution over Asia for the last two decades and projection for the next few decades, previously anticipated to inform a wide range of impact analysis.

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Applications of Coupled Fixed Points for Multivalued Maps in the Equilibrium in Duopoly Markets and in Aquatic Ecosystems

Axioms ◽

10.3390/axioms10020044 ◽

2021 ◽

Vol 10 (2) ◽

pp. 44

Author(s):

Gana Gecheva ◽

Miroslav Hristov ◽

Diana Nedelcheva ◽

Margarita Ruseva ◽

Boyan Zlatanov

Keyword(s):

Fixed Points ◽

Aquatic Ecosystems ◽

Market Equilibrium ◽

Multivalued Maps ◽

New Class ◽

Wide Range ◽

Coupled Fixed Points ◽

Ordered Pairs ◽

Duopoly Markets

We have obtained a new class of ordered pairs of multivalued maps that have pairs of coupled fixed points. We illustrate the main result with two examples that cover a wide range of models. We apply the main result in models in duopoly markets to get a market equilibrium and in aquatic ecosystems, also to get an equilibrium.

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Amphipathic Peptide Antibiotics with Potent Activity against Multidrug-Resistant Pathogens

Pharmaceutics ◽

10.3390/pharmaceutics13040438 ◽

2021 ◽

Vol 13 (4) ◽

pp. 438

Author(s):

Jingru Shi ◽

Chen Chen ◽

Dejuan Wang ◽

Ziwen Tong ◽

Zhiqiang Wang ◽

...

Keyword(s):

Membrane Damage ◽

Multidrug Resistant ◽

Peptide Antibiotics ◽

Biofilm Inhibition ◽

Amphipathic Peptide ◽

Host Defense Peptides ◽

Gram Negative ◽

Wide Range ◽

New Antibiotics ◽

Low Toxicity

The emergence and prevalence of multidrug-resistant (MDR) bacteria have posed a serious threat to public health. Of particular concern are methicillin-resistant Staphylococcus aureus (MRSA) and blaNDM, mcr-1 and tet(X)-positive Gram-negative pathogens. The fact that few new antibiotics have been approved in recent years exacerbates this global crisis, thus, new alternatives are urgently needed. Antimicrobial peptides (AMPs) originated from host defense peptides with a wide range of sources and multiple functions, are less prone to achieve resistance. All these characteristics laid the foundation for AMPs to become potential antibiotic candidates. In this study, we revealed that peptide WW307 displayed potent antibacterial and bactericidal activity against MDR bacteria, including MRSA and Gram-negative bacteria carrying blaNDM-5, mcr-1 or tet(X4). In addition, WW307 exhibited great biofilm inhibition and eradication activity. Safety and stability experiments showed that WW307 had a strong resistance against various physiological conditions and displayed relatively low toxicity. Mechanistic experiments showed that WW307 resulted in membrane damage by selectively targeting bacterial membrane-specific components, including lipopolysaccharide (LPS), phosphatidylglycerol (PG), and cardiolipin (CL). Moreover, WW307 dissipated membrane potential and triggered the production of reactive oxygen species (ROS). Collectively, these results demonstrated that WW307 represents a promising candidate for combating MDR pathogens.

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Revisiting the Functional Zoning Concept under Climate Change to Expand the Portfolio of Adaptation Options

Forests ◽

10.3390/f12030273 ◽

2021 ◽

Vol 12 (3) ◽

pp. 273

Author(s):

Samuel Royer-Tardif ◽

Jürgen Bauhus ◽

Frédérik Doyon ◽

Philippe Nolet ◽

Nelson Thiffault ◽

...

Keyword(s):

Climate Change ◽

Multiple Use ◽

Management Options ◽

Ecological Processes ◽

Adaptation Measures ◽

Good Communication ◽

Management Objectives ◽

Functional Zoning ◽

Wide Range ◽

Adaptation Options

Climate change is threatening our ability to manage forest ecosystems sustainably. Despite strong consensus on the need for a broad portfolio of options to face this challenge, diversified management options have yet to be widely implemented. Inspired by functional zoning, a concept aimed at optimizing biodiversity conservation and wood production in multiple-use forest landscapes, we present a portfolio of management options that intersects management objectives with forest vulnerability to better address the wide range of goals inherent to forest management under climate change. Using this approach, we illustrate how different adaptation options could be implemented when faced with impacts related to climate change and its uncertainty. These options range from establishing ecological reserves in climatic refuges, where self-organizing ecological processes can result in resilient forests, to intensive plantation silviculture that could ensure a stable wood supply in an uncertain future. While adaptation measures in forests that are less vulnerable correspond to the traditional functional zoning management objectives, forests with higher vulnerability might be candidates for transformative measures as they may be more susceptible to abrupt changes in structure and composition. To illustrate how this portfolio of management options could be applied, we present a theoretical case study for the eastern boreal forest of Canada. Even if these options are supported by solid evidence, their implementation across the landscape may present some challenges and will require good communication among stakeholders and with the public.

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Evaluating process-based integrated assessment models of climate change mitigation

Climatic Change ◽

10.1007/s10584-021-03099-9 ◽

2021 ◽

Vol 166 (1-2) ◽

Author(s):

Charlie Wilson ◽

Céline Guivarch ◽

Elmar Kriegler ◽

Bas van Ruijven ◽

Detlef P. van Vuuren ◽

...

Keyword(s):

Climate Change ◽

Integrated Assessment ◽

Climate Change Mitigation ◽

Evaluation Method ◽

Evaluation Research ◽

Evaluation Framework ◽

Systematic Evaluation ◽

Integrated Assessment Models ◽

Wide Range ◽

Change Mitigation

AbstractProcess-based integrated assessment models (IAMs) project long-term transformation pathways in energy and land-use systems under what-if assumptions. IAM evaluation is necessary to improve the models’ usefulness as scientific tools applicable in the complex and contested domain of climate change mitigation. We contribute the first comprehensive synthesis of process-based IAM evaluation research, drawing on a wide range of examples across six different evaluation methods including historical simulations, stylised facts, and model diagnostics. For each evaluation method, we identify progress and milestones to date, and draw out lessons learnt as well as challenges remaining. We find that each evaluation method has distinctive strengths, as well as constraints on its application. We use these insights to propose a systematic evaluation framework combining multiple methods to establish the appropriateness, interpretability, credibility, and relevance of process-based IAMs as useful scientific tools for informing climate policy. We also set out a programme of evaluation research to be mainstreamed both within and outside the IAM community.

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A Fish Galectin-8 Possesses Direct Bactericidal Activity

International Journal of Molecular Sciences ◽

10.3390/ijms22010376 ◽

2020 ◽

Vol 22 (1) ◽

pp. 376

Author(s):

Tengfei Zhang ◽

Shuai Jiang ◽

Li Sun

Keyword(s):

Bactericidal Activity ◽

Bacterial Pathogens ◽

Bactericidal Effect ◽

Immune Defense ◽

Carbohydrate Binding ◽

Dependent Manner ◽

Animal Cells ◽

Gram Negative ◽

Tongue Sole ◽

Wide Range

Galectins are a family of animal lectins with high affinity for β-galactosides. Galectins are able to bind to bacteria, and a few mammalian galectins are known to kill the bound bacteria. In fish, no galectins with direct bactericidal effect have been reported. In the present study, we identified and characterized a tandem repeat galectin-8 from tongue sole Cynoglossus semilaevis (designated CsGal-8). CsGal-8 possesses conserved carbohydrate recognition domains (CRDs), as well as the conserved HXNPR and WGXEE motifs that are critical for carbohydrate binding. CsGal-8 was constitutively expressed in nine tissues of tongue sole and up-regulated in kidney, spleen, and blood by bacterial challenge. When expressed in HeLa cells, CsGal-8 protein was detected both in the cytoplasm and in the micro-vesicles secreted from the cells. Recombinant CsGal-8 (rCsGal-8) bound to lactose and other carbohydrates in a dose dependent manner. rCsGal-8 bound to a wide range of gram-positive and gram-negative bacteria and was co-localized with the bound bacteria in animal cells. Lactose, fructose, galactose, and trehalose effectively blocked the interactions between rCsGal-8 and different bacteria. Furthermore, rCsGal-8 exerted potent bactericidal activity against some gram-negative bacterial pathogens by directly damaging the membrane and structure of the pathogens. Taken together, these results indicate that CsGal-8 likely plays an important role in the immune defense against some bacterial pathogens by direct bacterial interaction and killing.

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