Reviewing Interspecies Interactions as a Driving Force Affecting the Community Structure in Lakes via Cyanotoxins

The escalating occurrence of toxic cyanobacterial blooms worldwide is a matter of concern. Global warming and eutrophication play a major role in the regularity of cyanobacterial blooms, which has noticeably shifted towards the predomination of toxic populations. Therefore, understanding the effects of cyanobacterial toxins in aquatic ecosystems and their advantages to the producers are of growing interest. In this paper, the current literature is critically reviewed to provide further insights into the ecological contribution of cyanotoxins in the variation of the lake community diversity and structure through interspecies interplay. The most commonly detected and studied cyanobacterial toxins, namely the microcystins, anatoxins, saxitoxins, cylindrospermopsins and β-N-methylamino-L-alanine, and their ecotoxicity on various trophic levels are discussed. This work addresses the environmental characterization of pure toxins, toxin-containing crude extracts and filtrates of single and mixed cultures in interspecies interactions by inducing different physiological and metabolic responses. More data on these interactions under natural conditions and laboratory-based studies using direct co-cultivation approaches will provide more substantial information on the consequences of cyanotoxins in the natural ecosystem. This review is beneficial for understanding cyanotoxin-mediated interspecies interactions, developing bloom mitigation technologies and robustly assessing the hazards posed by toxin-producing cyanobacteria to humans and other organisms.

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Tree Diversity Reduces Fungal Endophyte Richness and Diversity in a Large-Scale Temperate Forest Experiment

Diversity ◽

10.3390/d11120234 ◽

2019 ◽

Vol 11 (12) ◽

pp. 234 ◽

Cited By ~ 2

Author(s):

Eric A. Griffin ◽

Joshua G. Harrison ◽

Melissa K. McCormick ◽

Karin T. Burghardt ◽

John D. Parker

Keyword(s):

Phylogenetic Diversity ◽

Large Scale ◽

High Throughput Sequencing ◽

Spatial Scales ◽

Fungal Endophytes ◽

Fungal Endophyte ◽

Tree Diversity ◽

Trophic Levels ◽

Community Diversity ◽

And Function

Although decades of research have typically demonstrated a positive correlation between biodiversity of primary producers and associated trophic levels, the ecological drivers of this association are poorly understood. Recent evidence suggests that the plant microbiome, or the fungi and bacteria found on and inside plant hosts, may be cryptic yet important drivers of important processes, including primary production and trophic interactions. Here, using high-throughput sequencing, we characterized foliar fungal community diversity, composition, and function from 15 broadleaved tree species (N = 545) in a recently established, large-scale temperate tree diversity experiment using over 17,000 seedlings. Specifically, we tested whether increases in tree richness and phylogenetic diversity would increase fungal endophyte diversity (the “Diversity Begets Diversity” hypothesis), as well as alter community composition (the “Tree Diversity–Endophyte Community” hypothesis) and function (the “Tree Diversity–Endophyte Function” hypothesis) at different spatial scales. We demonstrated that increasing tree richness and phylogenetic diversity decreased fungal species and functional guild richness and diversity, including pathogens, saprotrophs, and parasites, within the first three years of a forest diversity experiment. These patterns were consistent at the neighborhood and tree plot scale. Our results suggest that fungal endophytes, unlike other trophic levels (e.g., herbivores as well as epiphytic bacteria), respond negatively to increasing plant diversity.

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Cyanobacterial Toxins and Peptides in Lake Vegoritis, Greece

Toxins ◽

10.3390/toxins13060394 ◽

2021 ◽

Vol 13 (6) ◽

pp. 394

Author(s):

Sevasti-Kiriaki Zervou ◽

Kimon Moschandreou ◽

Aikaterina Paraskevopoulou ◽

Christophoros Christophoridis ◽

Elpida Grigoriadou ◽

...

Keyword(s):

Public Health ◽

Risk Assessment ◽

Simultaneous Determination ◽

Aquatic Ecosystems ◽

Human Exposure ◽

Bioactive Metabolites ◽

Cyanobacterial Toxins ◽

Major Threat ◽

Almost All

Cyanotoxins (CTs) produced by cyanobacteria in surface freshwater are a major threat for public health and aquatic ecosystems. Cyanobacteria can also produce a wide variety of other understudied bioactive metabolites such as oligopeptides microginins (MGs), aeruginosins (AERs), aeruginosamides (AEGs) and anabaenopeptins (APs). This study reports on the co-occurrence of CTs and cyanopeptides (CPs) in Lake Vegoritis, Greece and presents their variant-specific profiles obtained during 3-years of monitoring (2018–2020). Fifteen CTs (cylindrospermopsin (CYN), anatoxin (ATX), nodularin (NOD), and 12 microcystins (MCs)) and ten CPs (3 APs, 4 MGs, 2 AERs and aeruginosamide (AEG A)) were targeted using an extended and validated LC-MS/MS protocol for the simultaneous determination of multi-class CTs and CPs. Results showed the presence of MCs (MC-LR, MC-RR, MC-YR, dmMC-LR, dmMC-RR, MC-HtyR, and MC-HilR) and CYN at concentrations of <1 μg/L, with MC-LR (79%) and CYN (71%) being the most frequently occurring. Anabaenopeptins B (AP B) and F (AP F) were detected in almost all samples and microginin T1 (MG T1) was the most abundant CP, reaching 47.0 μg/L. This is the first report of the co-occurrence of CTs and CPs in Lake Vegoritis, which is used for irrigation, fishing and recreational activities. The findings support the need for further investigations of the occurrence of CTs and the less studied cyanobacterial metabolites in lakes, to promote risk assessment with relevance to human exposure.

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A force measuring microsystem bases on electrothermal V-shaped actuator

Vietnam Journal of Mechanics ◽

10.15625/0866-7136/14823 ◽

2020 ◽

Author(s):

Pham Hong Phuc

Keyword(s):

Driving Force ◽

Driving Voltage ◽

Shaped Beam ◽

Ansys Simulation ◽

Melting Phenomenon ◽

Beam Displacement ◽

Previous Design ◽

Amplification Mechanism ◽

Measured Displacement

This paper describes design and calculation of an electrothermal V-shaped actuator (EVA) and an amplification mechanism integrated into a force measuring microsystem (FMMS), aims to apply for characterization of a micro beam. Displacement and driving force are generated by thermal expansion of the V-shaped silicon beams while applying a voltage to the electrodes of the EVA. ANSYS simulation helps to find out the relations between thermal force and displacement corresponding to driving voltage and determine the temperature of V-shaped beam at various applying voltages. In our simulation, with applying voltage Um = 38 volt for six pairs of V-shaped beam, the maximal temperature of the beam reaches approximately to 1100°C and causes a melting phenomenon of the silicon beam. The additional amplification mechanism allows actuator's displacement to be 6 times larger than before the improvement, thus the bending deformation of the micro beam can be seen perfectly, i.e. the force loading on the beam can be computed more exactly via a measured displacement of the beam tip. In addition, this FMMS has smaller size and supplies a larger beam's deformation at the same voltage in comparison with previous design.

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Characterization of the quality of the gametes and sex steroid levels during spring and summer spawning events in pejerrey Odontesthes bonariensis reared under natural conditions of temperature and photoperiod

Aquaculture Research ◽

10.1111/are.14517 ◽

2020 ◽

Vol 51 (4) ◽

pp. 1706-1711

Author(s):

Tomás Chalde ◽

Leandro Andrés Miranda

Keyword(s):

Sex Steroid ◽

Natural Conditions ◽

Odontesthes Bonariensis

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Characterization of the microbial community diversity and composition of the coast of Lebanon: Potential for petroleum oil biodegradation

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2019.110508 ◽

2019 ◽

Vol 149 ◽

pp. 110508 ◽

Cited By ~ 1

Author(s):

Hamdan Z. Hamdan ◽

Darine A. Salam ◽

Pascal E. Saikaly

Keyword(s):

Microbial Community ◽

Community Diversity ◽

Microbial Community Diversity ◽

Oil Biodegradation ◽

Petroleum Oil

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Exploring Utilization of Recycled Agricultural Biomass in Constructed Wetlands: Characterization of the Driving Force for High-Rate Nitrogen Removal

Environmental Science & Technology ◽

10.1021/acs.est.8b04871 ◽

2019 ◽

Vol 53 (3) ◽

pp. 1258-1268 ◽

Cited By ~ 8

Author(s):

Lixia Jia ◽

Enfang Gou ◽

Hai Liu ◽

Shaoyong Lu ◽

Shubiao Wu ◽

...

Keyword(s):

Constructed Wetlands ◽

Nitrogen Removal ◽

Driving Force ◽

High Rate ◽

Agricultural Biomass

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Massively parallel screening of synthetic microbial communities

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1900102116 ◽

2019 ◽

Vol 116 (26) ◽

pp. 12804-12809 ◽

Cited By ~ 43

Author(s):

Jared Kehe ◽

Anthony Kulesa ◽

Anthony Ortiz ◽

Cheri M. Ackerman ◽

Sri Gowtham Thakku ◽

...

Keyword(s):

Microbial Communities ◽

Massively Parallel ◽

Phenotypic Characterization ◽

Interspecies Interactions ◽

Additional Species ◽

Plant Symbiont ◽

Complementary Approach ◽

Potential Applications ◽

Synthetic Microbial Communities

Microbial communities have numerous potential applications in biotechnology, agriculture, and medicine. Nevertheless, the limited accuracy with which we can predict interspecies interactions and environmental dependencies hinders efforts to rationally engineer beneficial consortia. Empirical screening is a complementary approach wherein synthetic communities are combinatorially constructed and assayed in high throughput. However, assembling many combinations of microbes is logistically complex and difficult to achieve on a timescale commensurate with microbial growth. Here, we introduce the kChip, a droplets-based platform that performs rapid, massively parallel, bottom-up construction and screening of synthetic microbial communities. We first show that the kChip enables phenotypic characterization of microbes across environmental conditions. Next, in a screen of ∼100,000 multispecies communities comprising up to 19 soil isolates, we identified sets that promote the growth of the model plant symbiontHerbaspirillum frisingensein a manner robust to carbon source variation and the presence of additional species. Broadly, kChip screening can identify multispecies consortia possessing any optically assayable function, including facilitation of biocontrol agents, suppression of pathogens, degradation of recalcitrant substrates, and robustness of these functions to perturbation, with many applications across basic and applied microbial ecology.

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Formation of Twinned WC Grains during Carbonization of Eta Phase (W3Co3C)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.1189 ◽

2007 ◽

Vol 534-536 ◽

pp. 1189-1192 ◽

Cited By ~ 4

Author(s):

Jong Dae Kim ◽

Kern Woo Lee ◽

Joo Wan Lee ◽

Moshe Sharon ◽

Suk Joong L. Kang

Keyword(s):

Experimental Observation ◽

Driving Force ◽

Carbon Activity ◽

Low Carbon ◽

High Carbon ◽

Sem And Tem ◽

High Supersaturation ◽

Co Alloys

Twinned WC grains are sometimes observed in WC powder and sintered WC-Co alloys. The present investigation has studied the formation of twinned WC grains during carburization of an Eta phase. Eta grains were carburized at 700-1450°C for 1 min to 9 h. Twinned WC grains formed during the carburization. Crystallographic characterization of the formed twins were made using SEM and TEM. The formation of twins was found to be affected by the carbon activity during carburization. The twins formed under high carbon activities while no twins formed under low carbon activities. Two kinds of twins with different orientations were observed. The present experimental observation suggests that the twins formed via 2-dimensional nucleation and layer-bylayer growth on small WC clusters under high supersaturation and high driving force for the growth of WC grains.

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