Drivers of dinoflagellate benthic cyst assemblages in the NW Patagonian Fjords System and its adjacent oceanic shelf, with a focus on harmful species

2021 ◽  
Vol 785 ◽  
pp. 147378
Author(s):  
Camilo Rodríguez-Villegas ◽  
Matthew R. Lee ◽  
Pablo Salgado ◽  
Rosa I. Figueroa ◽  
Ángela Baldrich ◽  
...  
Keyword(s):  
Harmful Species ◽  
Patagonian Fjords

scholarly journals Improved Glucose Recovery from Sicyos angulatus by NaOH Pretreatment and Application to Bioethanol Production

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 245
Author(s):  
Hyung-Eun An ◽  
Kang Hyun Lee ◽  
Ye Won Jang ◽  
Chang-Bae Kim ◽  
Hah Young Yoo
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Alternative Energy ◽  
Invasive Plant ◽  
Food Resource ◽  
Raw Material ◽  
Control Group ◽  
Bioethanol Production ◽  
Naoh Pretreatment ◽  
Glucose Recovery ◽  
Harmful Species

As greenhouse gases and environmental pollution become serious, the demand for alternative energy such as bioethanol has rapidly increased, and a large supply of biomass is required for bioenergy production. Lignocellulosic biomass is the most abundant on the planet and a large part of it, the second-generation biomass, has the advantage of not being a food resource. In this study, Sicyos angulatus, known as an invasive plant (harmful) species, was used as a raw material for bioethanol production. In order to improve enzymatic hydrolysis, S. angulatus was pretreated with different NaOH concentration at 121 °C for 10 min. The optimal NaOH concentration for the pretreatment was determined to be 2% (w/w), and the glucan content (GC) and enzymatic digestibility (ED) were 46.7% and 55.3%, respectively. Through NaOH pretreatment, the GC and ED of S. angulatus were improved by 2.4-fold and 2.5-fold, respectively, compared to the control (untreated S. angulatus). The hydrolysates from S. angulatus were applied to a medium for bioethanol fermentation of Saccharomyces cerevisiae K35. Finally, the maximum ethanol production was found to be 41.3 g based on 1000 g S. angulatus, which was 2.4-fold improved than the control group.

scholarly journals Investigation of phagotrophy in natural assemblages of the benthic dinoflagellates Ostreopsis, Prorocentrum and Coolia

2017 ◽  
Vol 65 (3) ◽  
pp. 392-399 ◽  
Author(s):  
Eliliane Vasconcelos Corrêa Almada ◽  
Wanderson Fernandes de Carvalho ◽  
Silvia Mattos Nascimento
Keyword(s):  
Fluorescence Microscopy ◽  
Rio De Janeiro ◽  
Nutritional Ecology ◽  
Harmful Algae ◽  
Benthic Dinoflagellates ◽  
Nutritional Strategy ◽  
Nutritional Strategies ◽  
Harmful Species

Abstract Mixotrophy has been shown to be a common trait among dinoflagellates and its importance in the nutritional ecology of harmful algae has been hypothesized. Benthic harmful species have not been extensively investigated as their planktonic counterparts and there are major gaps in the knowledge of their nutritional strategies. In this study the occurrence of phagotrophy was investigated in natural assemblages of benthic dinoflagellates using epi-fluorescence microscopy with DAPI and LysoSensor staining. The study was conducted at five sites along the coast of Rio de Janeiro that were visited in January, August and December 2010. In total, 1659 dinoflagellate cells were observed. From these, only 0.4% of 1195 Ostreopsis cf. ovata and 2.2% of 134 Coolia spp. cells presented evidence of phagotrophy with vacuoles stained by LysoSensor or a DAPI (4',6-diamidino-2-phenylindole) stained inclusion. Stained vacuoles were not registered in the 330 Prorocentrum spp. cells observed. Few O. cf. ovata cells contained round red inclusions ("red spots") that were not stained either by DAPI or LysoSensor, suggesting that these structures are not ingested prey. The results showed that phagotrophy was not a frequent nutritional strategy in benthic dinoflagellates during the study period.

scholarly journals BIOLOGICAL METHOD OF STRUGGLE AGAINST THE BASIC WRECKERS OF THE SWEET CORN IN R. OF MOLDOVA

1970 ◽  
Vol 62 ◽  
Author(s):  
Asea Timus ◽  
N. Croitoru
Keyword(s):  
Sweet Corn ◽  
Ecological Status ◽  
Climatic Conditions ◽  
Biological Method ◽  
Trichogramma Evanescens ◽  
Biological Methods ◽  
Year 2000 ◽  
Different Cultures ◽  
The Given ◽  
Harmful Species

Every year, the demand of ecological products in the world is increasing more and more. Republic of Moldova also aspires to expand the areas of agricultural crops to get production with the "ecological" status. The sweet corn, is one of these cultures and every year the areas increase. However, because of the considerable develop of harmful insects on cultural fields, the damage reaches up to 15-20 % and more it is necessary to take measures of struggle. One of these, is a biological method and in this case it has appeared effective. For the period of sweet corn cultivation, excepting for the technology observance of cultivation of the given culture, there have been used biological methods of struggle against harmful insects. Depending on climatic conditions of each zone of the country where it is grown up this culture, different species of harmful insects develop. In R. Moldova, begining with year 2000, have been registered the following harmful species of insects on sweet corn: Aphis spp. (Aphididae); Agrotis spp. (Elateridae); Blaps halophila Fisch. (Tenebrionidae); Phylotreta spp. (Chrysomelidae); Helicoverpa armigera Hubner (Noctuidae) Ostrinia nubilalis Hb. (Pyraustidae). The constant useful fauna which develops due to these harmful species is: Nabis spp. (Miridae); Chrysopa spp., (Chrysopidae); Coccinella spp. (Coccinelidae) and others. That is why, annually are let out individuals from species Trichogramma evanescens W., to reduce the number of harmful species H. armigera Hubner. This species annually damages on different cultures, including on sweet corn. The results on released trichogrammas in 2005, for struggle against harmful species H. armigera Hubner, are presented in this work.

scholarly journals Multiple agents managing a harmful species population should either work together to control it or split their duties to eradicate it

2020 ◽  
Vol 117 (19) ◽  
pp. 10210-10217 ◽  
Author(s):  
Adam Lampert
Keyword(s):  
General Theorem ◽  
Dynamic Game ◽  
Theoretic Model ◽  
Multiple Agents ◽  
Severe Damage ◽  
Global Challenge ◽  
Species Population ◽  
Game Theoretic ◽  
Game Theoretic Model ◽  
Harmful Species

The management of harmful species, including invasive species, pests, parasites, and diseases, is a major global challenge. Harmful species cause severe damage to ecosystems, biodiversity, agriculture, and human health. In particular, managing harmful species often requires cooperation among multiple agents, such as landowners, agencies, and countries. Each agent may have incentives to contribute less to the treatment, leaving more work for other agents, which may result in inefficient treatment. A central question is, therefore, how should a policymaker allocate treatment duties among the agents? Specifically, should the agents work together in the same area, or should each agent work only in a smaller area designated just for her/him? We consider a dynamic game-theoretic model, where a Nash equilibrium corresponds to a possible set of contributions that the agents could adopt over time. In turn, the allocation by the policymaker determines which of the Nash equilibria could be adopted, which allows us to compare the outcome of various allocations. Our results show that fewer agents can abate the harmful species population faster, but more agents can better control the population to keep its density lower. We prove this result in a general theorem and demonstrate it numerically for two case studies. Therefore, following an outbreak, the better policy would be to split and assign one or a few agents to treat the species in a given location, but if controlling the harmful species population at some low density is needed, the agents should work together in all of the locations.

scholarly journals STRATEGIE INNOVATIVE PER IL CONTROLLO DI ZANZARE, VETTORI DI ORGANISMI PATOGENI

2020 ◽  
Author(s):  
Giuliano Gasperi
Keyword(s):  
Reproductive Behaviour ◽  
Pest Species ◽  
Gene Drive ◽  
West Nile Fever ◽  
Environmentally Safe ◽  
Safe Control ◽  
Human Infections ◽  
Species Being ◽  
Harmful Species

Mosquitoes are the most dangerous insect species being the vectors of the pathogens causing the most widespread diseases as Malaria, Dengue fever, Chikungunya, West Nile fever, Yellow fever, Zika. Several species of the Anopheles, Aedes and Culex are responsable for millions of human infections causing hundreds of thousands of deaths per year. This causes dramatic socio-economic and health consequences, especially in developing countries. Harmful insects are controlled using chemical insecticides which cause insecticide resistance and environmental pollution, due to long term use. In the second half of the 20th century, new insect environmentally safe control stategies were been developed, based on the insect’s reproductive behaviour. Notably, the Sterile Insect Technique (SIT) has been successfully applied against some dipteran pest species in several regions of the World. It drived several research efforts to increase our knowledge of the biology of the harmful species. SIT improvements have been also achieved with several molecular biology approaches and transgene technologies such as the innovative RIDL, cytoplasmic incompatibility (CI) and gene drive.

scholarly journals Dynamics of Cyanobacteria and Related Environmental Drivers in Freshwater Bodies Affected by Mitten Crab Culturing: A Study of Lake Guchenghu, China

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2468
Author(s):  
Hongmin Li ◽  
Huihui Chen ◽  
Xiaohong Gu ◽  
Zhigang Mao ◽  
Qingfei Zeng ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Phytoplankton Biomass ◽  
Dominant Species ◽  
N:P Ratio ◽  
Water Bodies ◽  
Environmental Drivers ◽  
Mitten Crab ◽  
Total Phytoplankton ◽  
Freshwater Bodies ◽  
Harmful Species

Mitten crab aquaculture is prevalent in China, however, knowledge about the threat of cyanobacteria in mitten crab aquaculture-impacted water bodies is limited. Here, seasonal variations of cyanobacteria and their relationships with environmental factors were investigated for Lake Guchenghu area. Results suggested the changes of cyanobacteria community in crab ponds distinguished from the adjacent lake. In the lake, cyanobacterial biomass (3.86 mg/L, 34.6% of the total phytoplankton) was the highest in autumn with the dominance of Oscillatoria, Aphanocapsa and Pesudanabaena. By contrast, in crab ponds, cyanobacteria (46.80 mg/L, 97.2% of the total phytoplankton biomass) were the most abundant in summer when Pesudanabaena and Raphidiopsis were the dominant species. Of particular note was that obviously higher abundance of filamentous and potentially harmful species (e.g., Raphidiopsis raciborskii and Dolichospermum circinale) were observed in ponds compared to the lake. Specifically, water depth (WD), permanganate index (CODMn), total phosphorus (TP), N:P ratio, and NO 2 −-N were the key environmental variables affected cyanobacteria composition. For crab ponds, N:P ratio, water temperature (WT) and TP were the potential environmental drivers of cyanobacteria development. This study highlighted the fact that mitten crab culture had non-negligible influences on the cyanobacteria community and additional attention should be paid to the cyanobacteria dynamics in mitten crab culture-impacted water bodies, especially for those potentially harmful species.

scholarly journals Oxidant and Antioxidant Effects of Gentisic Acid in a 177Lu-Labelled Methionine-Containing Minigastrin Analogue

2020 ◽  
Vol 13 (2) ◽  
pp. 107-119
Author(s):  
Victoria Trindade ◽  
Henia Balter
Keyword(s):  
Selective Oxidation ◽  
Gentisic Acid ◽  
Methionine Residue ◽  
Radiation Induced ◽  
Binding Peptides ◽  
Ph Dependent ◽  
The Stability ◽  
Harmful Species ◽  
Antioxidant Effects ◽  
Radiolabelled Peptide

Background: The radiolabelling of receptor-binding peptides for therapy is a challenge since the peptide itself is exposed (during labelling, storage and transport) to radiation-induced damage, directly or indirectly, in aqueous solution. Hence, the use of radiostabilizers seems to be mandatory, especially in peptide molecules that contain radiation-sensitive amino acids. Objective: The aim of this study was to investigate the effect of two stabilizers, gentisic acid and methionine, to delve into how each of them affects the radiolabelling and stability of the minigastrin analogue [177Lu]Lu-DOTA-His-His-Glu-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2 through the analysis of the 22 species distinguished over time by an optimized HPLC system. Methods: The stabilizers, in different combinations, were present from the beginning of the labelling process carried out at 96 °C for 15 min. The stability was studied for up to 7 days. Results: The unexpected selective oxidation of the methionine residue of the radiolabelled peptide, promoted by gentisic acid, led to studying the effect of pH, from 3.5 to 6.0, in the presence of only this stabilizer. A pH-dependent antioxidant behaviour was revealed, showing a decrease in peptide impurities but an increase in the selective oxidation as the pH was increased. Conclusion: The selective oxidation of the methionine residue could be induced by oxidizing species probably produced in the reaction between gentisic acid and free radicals of water, during the protection of the radiolabelled peptide from the attack of these harmful species. Therefore, the addition of methionine becomes necessary to effectively decrease this selective oxidation in the methioninecontaining peptide.

Hypoxia in Chilean Patagonian Fjords

2014 ◽  
Vol 129 ◽  
pp. 62-74 ◽  
Author(s):  
Nelson Silva ◽  
Cristian A. Vargas
Keyword(s):  
Patagonian Fjords

scholarly journals Experimental assessment of the effect of UVB radiation on plankton community metabolism along the Southeastern Pacific off Chile

2012 ◽  
Vol 9 (4) ◽  
pp. 1267-1276 ◽  
Author(s):  
N. Godoy ◽  
A. Canepa ◽  
S. Lasternas ◽  
E. Mayol ◽  
S. Ruíz-Halpern ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Current System ◽  
Uvb Radiation ◽  
Net Community Production ◽  
Humboldt Current ◽  
Community Metabolism ◽  
Southeastern Pacific ◽  
Humboldt Current System ◽  
Patagonian Fjords ◽  
Community Production

Abstract. The potential effects of UV on community metabolism (NCP, GPP and R) were assessed along the Southeast Pacific off the Chilean coast during the Humbold-2009 cruise (54.80° S–23.85° S) on board R/V Hespérides from 5 to 15 March 2009. Estimates of community metabolism were performed at eight stations, including three stations on Patagonian fjords and five stations on the Humboldt Current System. The effect of UVB radiation on net community production (NCP) was evaluated at the stations in the Humboldt Current system by comparing metabolic rates derived using quartz bottles, largely transparent to UVB, and borosilicate glass, which is opaque to UVB and part of UVA, incubated under the ambient solar radiation. Autotrophic planktonic communities with variable NCP prevailed along the area, with the highest NCP rates (7.1–11.1 mmol O2 m−3 d−1) observed in the Patagonian fjords and the northernmost station. All five experiments showed significantly different NCP rates between communities incubated under the full ambient radiation and those incubated under reduced UVB. One of the experiments showed elevated NCP when the community was exposed to the full solar radiation, while four experiments showed a significantly lower NCP in the presence of UVB. These results suggest that the intense UVB radiation in this area, partly inhibits NCP in the Southwest Pacific off Chile.

Sign in / Sign up

Export Citation Format

Share Document