Biogeochemical Niches of Fe-cycling Communities Influencing Heavy Metal Transport Along the Rio Tinto, Spain

2021 ◽  
Author(s):  
Sergey M. Abramov ◽  
Daniel Straub ◽  
Julian Tejada ◽  
Lars Grimm ◽  
Franziska Schädler ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Microbial Community ◽  
Microbial Communities ◽  
Estuarine Water ◽  
Saline Environments ◽  
Dna And Rna ◽  
Rio Tinto ◽  
The Impact ◽  
Río Tinto

In the mining-impacted Rio Tinto, Spain, Fe-cycling microorganisms influence the transport of heavy metals (HMs) into the Atlantic Ocean. However, it remains largely unknown how spatial and temporal hydrogeochemical gradients along the Rio Tinto shape the composition of Fe-cycling microbial communities and how this in turn affects HM mobility. Using a combination of DNA- and RNA-based 16S rRNA (gene) amplicon sequencing and hydrogeochemical analyses, we explored the impact of pH, Fe(III), Fe(II) and Cl - on Fe-cycling microorganisms. We showed that the water column at the acidic (pH 2.2) middle course of the river was colonized by Fe(II) oxidizers affiliating with Acidithiobacillus and Leptospirillum. At the upper estuary, daily fluctuations of pH (2.7-3.7) and Cl - (6.9-16.6 g/L) contributed to the establishment of a unique microbial community, including Fe(II) oxidizers belonging to Acidihalobacter , Marinobacter and Mariprofundus identified at this site. Furthermore, DNA- and RNA-based profiles of the benthic community suggested that acidophilic and neutrophilic Fe(II) oxidizers (e.g., Acidihalobacter , Marinobacter and Mariprofundus ), Fe(III) reducers (e.g., Thermoanaerobaculum ) and sulfate-reducing bacteria drive the Fe cycle in the estuarine sediments. RNA-based relative abundances of Leptospirillum at the middle course as well as abundances of Acidohalobacter and Mariprofundus at the upper estuary were higher, compared to DNA-based results, suggesting potentially higher level of activity of these taxa. Based on our findings, we propose a model of how tidal water affects the composition and activity of the Fe-cycling taxa, playing an important role in the transport of HMs (e.g., As, Cd, Cr and Pb) along the Rio Tinto. Importance The estuary of the Rio Tinto is a unique environment in which extremely acidic, heavy metal- and especially iron-rich river water is mixed with seawater. Due to the mixing events, the estuarine water is characterized by a low pH, almost sea water salinity and high concentrations of bioavailable iron. The unusual hydrogeochemistry maintains unique microbial communities in the estuarine water and in the sediment. These communities include halotolerant iron-oxidizing microorganisms which typically inhabit acidic saline environments and marine iron-oxidizing microorganisms, which, in opposite, are not typically found in acidic environments. Furthermore, highly saline estuarine water favored the prosperity of acidophilic heterotrophs, typically inhabiting brackish and saline environments. The Rio Tinto estuarine sediment harbored a diverse microbial community with both, acidophilic and neutrophilic members that can mediate the iron cycle, and in turn, can directly impact the mobility and transport of heavy metals in the Rio Tinto estuary.

scholarly journals Heavy Metal Tolerance Genes Associated With Contaminated Sediments From an E-Waste Recycling River in Southern China

2021 ◽  
Vol 12 ◽  
Author(s):  
Shengqiao Long ◽  
Hui Tong ◽  
Xuxiang Zhang ◽  
Shuyu Jia ◽  
Manjia Chen ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Microbial Community ◽  
Microbial Communities ◽  
Southern China ◽  
Risk Index ◽  
River Sediments ◽  
Microbial Community Composition ◽  
Heavy Metal Tolerance ◽  
Waste Recycling ◽  
The Impact

Heavy metal pollution that results from electronic waste (e-waste) recycling activities has severe ecological environmental toxicity impacts on recycling areas. The distribution of heavy metals and the impact on the bacteria in these areas have received much attention. However, the diversity and composition of the microbial communities and the characteristics of heavy metal resistance genes (HMRGs) in the river sediments after long-term e-waste contamination still remain unclear. In this study, eight river sediment samples along a river in a recycling area were studied for the heavy metal concentration and the microbial community composition. The microbial community consisted of 13 phyla including Firmicutes (ranging from 10.45 to 36.63%), Proteobacteria (11.76 to 32.59%), Actinobacteria (14.81 to 27.45%), and unclassified bacteria. The abundance of Firmicutes increased along with the level of contaminants, while Actinobacteria decreased. A canonical correspondence analysis (CCA) showed that the concentration of mercury was significantly correlated with the microbial community and species distribution, which agreed with an analysis of the potential ecological risk index. Moreover, manually curated HMRGs were established, and the HMRG analysis results according to Illumina high-throughput sequencing showed that the abundance of HMRGs was positively related to the level of contamination, demonstrating a variety of resistance mechanisms to adapt, accommodate, and live under heavy metal-contaminated conditions. These findings increase the understanding of the changes in microbial communities in e-waste recycling areas and extend our knowledge of the HMRGs involved in the recovery of the ecological environment.

scholarly journals Determining Rates of Change and Evaluating Group-Level Resiliency Differences in Hyporheic Microbial Communities in Response to Fluvial Heavy-Metal Deposition

2004 ◽  
Vol 70 (8) ◽  
pp. 4756-4765 ◽  
Author(s):  
Kevin P. Feris ◽  
Philip W. Ramsey ◽  
Matthias Rillig ◽  
Johnnie N. Moore ◽  
James E. Gannon ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Microbial Community ◽  
Microbial Communities ◽  
Metal Contamination ◽  
Heavy Metal Contamination ◽  
Indigenous Populations ◽  
Curvilinear Relationship ◽  
Group Level ◽  
Rates Of Change

ABSTRACT Prior field studies by our group have demonstrated a relationship between fluvial deposition of heavy metals and hyporheic-zone microbial community structure. Here, we determined the rates of change in hyporheic microbial communities in response to heavy-metal contamination and assessed group-level differences in resiliency in response to heavy metals. A controlled laboratory study was performed using 20 flowthrough river mesocosms and a repeated-measurement factorial design. A single hyporheic microbial community was exposed to five different levels of an environmentally relevant metal treatment (0, 4, 8, 16, and 30% sterilized contaminated sediments). Community-level responses were monitored at 1, 2, 4, 8, and 12 weeks via denaturing gradient gel electrophoresis and quantitative PCR using group-specific primer sets for indigenous populations most closely related to the α-, β-, and γ-proteobacteria. There was a consistent, strong curvilinear relationship between community composition and heavy-metal contamination (R 2 = 0.83; P < 0.001), which was evident after only 7 days of metal exposure (i.e., short-term response). The abundance of each phylogenetic group was negatively affected by the heavy-metal treatments; however, each group recovered from the metal treatments to a different extent and at a unique rate during the course of the experiment. The structure of hyporheic microbial communities responded rapidly and at contamination levels an order of magnitude lower than those shown to elicit a response in aquatic macroinvertebrate assemblages. These studies indicate that hyporheic microbial communities are a sensitive and useful indicator of heavy-metal contamination in streams.

scholarly journals Study of Heavy Metals and Microbial Communities in Contaminated Sediments Along an Urban Estuary

2021 ◽  
Vol 8 ◽  
Author(s):  
Jun Yi ◽  
Linus Shing Him Lo ◽  
Hongbin Liu ◽  
Pei-Yuan Qian ◽  
Jinping Cheng
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Microbial Community ◽  
Microbial Communities ◽  
Ecological Risk ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Risk Index ◽  
Estuarine Sediments ◽  
Yangtze River Estuary

Estuarine sediments are increasingly contaminated by heavy metals as a result of urbanization and human activities. Continuous multi-heavy metal accumulation in the ecosystem can provoke new effects on top of the complex environmental interactions already present in estuarine ecosystems. It is important to study their integrated influence on imperative microbial communities to reflect on the environmental and ecological risks they may impose. Inductively coupled plasma optical emission spectroscopy analysis for five metals Cd, Cr, Cu, Pb, and Zn showed that Cr and Cu concentrations in intertidal sediments of the urbanized Yangtze River estuary in China have consistently exceeded respective threshold effect concentration (TEC) levels. The geo-accumulation and potential ecological risk index results of the five metals showed that all sampling sites were weakly to moderately polluted, and at considerable to high ecological risk, respectively. Redundancy and correlation analyses showed that Zn followed by Cr in the ecosystem were explanatory of the shifts in recorded microbial community structures. However, the spatial variation in metal concentrations did not correspond to the selection of metal resistance genes (MRGs). Unlike many other dominant bacterial taxa, most of the sulfate-reducing bacteria (SRB) and associated sulfate respiration as the dominant microbially contributed ecological function were found to negatively correlate with Zn and total heavy metal pollution. Zn concentration was proposed to be a potent indicator for heavy metal pollution-associated microbial community compositional shifts under urbanized estuarine conditions. The associations between heavy metals and estuarine microbial communities in this study demonstrate the influence of heavy metals on microbial community structure and adaptations that is often overshadowed by environmental factors (i.e., salinity and nutrients).

scholarly journals Seasonal Dynamics of Shallow-Hyporheic-Zone Microbial Community Structure along a Heavy-Metal Contamination Gradient

2004 ◽  
Vol 70 (4) ◽  
pp. 2323-2331 ◽  
Author(s):  
Kevin P. Feris ◽  
Philip W. Ramsey ◽  
Chris Frazar ◽  
Matthias Rillig ◽  
Johnnie N. Moore ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Community Structure ◽  
Microbial Community ◽  
Microbial Communities ◽  
Microbial Community Structure ◽  
Metal Contamination ◽  
Hyporheic Zone ◽  
Heavy Metal Contamination ◽  
The Difference

ABSTRACT Heavy metals contaminate numerous freshwater streams and rivers worldwide. Previous work by this group demonstrated a relationship between the structure of hyporheic microbial communities and the fluvial deposition of heavy metals along a contamination gradient during the fall season. Seasonal variation has been documented in microbial communities in numerous terrestrial and aquatic environments, including the hyporheic zone. The current study was designed to assess whether relationships between hyporheic microbial community structure and heavy-metal contamination vary seasonally by monitoring community structure along a heavy-metal contamination gradient for more than a year. No relationship between total bacterial abundance and heavy metals was observed (R 2 = 0.02, P = 0.83). However, denaturing gradient gel electrophoresis pattern analysis indicated a strong and consistent linear relationship between the difference in microbial community composition (populations present) and the difference in the heavy metal content of hyporheic sediments throughout the year (R 2 = 0.58, P < 0.001). Correlations between heavy-metal contamination and the abundance of four specific phylogenetic groups (most closely related to the α, β, and γ-proteobacteria and cyanobacteria) were apparent only during the fall and early winter, when the majority of organic matter is deposited into regional streams. These seasonal data suggest that the abundance of susceptible populations responds to heavy metals primarily during seasons when the potential for growth is highest.

scholarly journals Heavy-Metal Contents and the Impact of Roasting on Polyphenols, Caffeine, and Acrylamide in Specialty Coffee Beans

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1310
Author(s):  
Matúš Várady ◽  
Sylwester Ślusarczyk ◽  
Jana Boržíkova ◽  
Katarína Hanková ◽  
Michaela Vieriková ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Dry Matter ◽  
Green Beans ◽  
Caffeoylquinic Acids ◽  
Coffee Beans ◽  
Metal Contents ◽  
Specialty Coffee ◽  
Quantitative Analyses ◽  
The Impact

The aim of this study was to determine the effect of roasting on the contents of polyphenols (PPH), acrylamide (AA), and caffeine (CAF) and to analyze heavy metals in specialty coffee beans from Colombia (COL) and Nicaragua (NIC). Samples of NIC were naturally processed and COL was fermented anaerobically. Green beans from COL (COL-GR) and NIC (NIC-GR) were roasted at two levels, light roasting (COL-LIGHT and NIC-LIGHT) and darker roasting (COL-DARK and NIC-DARK), at final temperatures of 210 °C (10 min) and 215 °C (12 min), respectively. Quantitative analyses of PPH identified caffeoylquinic acids (CQA), feruloylquinic acids, and dicaffeoylquinic acids. Isomer 5-CQA was present at the highest levels and reached 60.8 and 57.7% in COL-GR and NIC-GR, 23.4 and 29.3% in COL-LIGHT and NIC-LIGHT, and 18 and 24.2% in COL-DARK and NIC-DARK, respectively, of the total PPH. The total PPH contents were highest in COL-GR (59.76 mg/g dry matter, DM). Roasting affected the contents of PPH, CAF, and AA (p < 0.001, p < 0.011 and p < 0.001, respectively). Nickel and cadmium contents were significantly higher in the COL-GR than in the NIC-GR beans. Darker roasting decreased AA content, but light roasting maintained similar amounts of CAF and total PPH.

scholarly journals Physico-chemical variability and heavy metal pollution of surface sediment in a non-channeled section of Dilúvio Stream (Southern Brazil) and the influence of channeled section in sediment pollution

2019 ◽  
Vol 14 (1) ◽  
pp. 1 ◽  
Author(s):  
Pedro Alexandre Sodrzeieski ◽  
Leonardo Capeleto de Andrade ◽  
Tales Tiecher ◽  
Flávio Anastácio de Oliveira Camargo
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Total Concentration ◽  
Mineralogical Composition ◽  
Sediment Pollution ◽  
Anthropogenic Influence ◽  
Southern Brazil ◽  
Physico Chemical ◽  
Chemical Variability ◽  
The Impact

Dilúvio Stream flows through an area with a great population density in Porto Alegre, Southern Brazil. The anthropogenic influence in the surroundings impacted negatively the quality of the sediments of Dilúvio Stream and Lake Guaíba. This study evaluated the physico-chemical variability of surface sediments in a non-channeled section of Dilúvio Stream. Additionally, we compared the concentration of several heavy metals in this section with data from previous studies in the margins of Lake Guaíba near the outflow of Dilúvio Stream in order to evaluate the impact of urbanization on sediment pollution. The pH, bulk density, particle-size distribution, electrical conductivity, organic carbon, assimilable phosphorus, total nitrogen, mineralogical composition (X-ray diffractogram) and pseudo total concentration of several metals (Fe, Al, Ca, Mg, Na, K, Mn, Ba, Zn, V, As, Pb, Cu, Cr, Co, Ni, Cd, Mo, and Se) were evaluated. The results showed that the sediments in the non-channeled section of Dilúvio Stream are predominantly sandy, with heavy metal contents below the quality reference values. Quartz and feldspar predominated in all sites. The concentration of Zn, Pb, Cu, Cr, and Ni were lower than that observed in the margins of Lake Guaíba near the outflow of Dilúvio Stream, possibly due to pollution input throughout the channeled section. The Dilúvio Stream shows indications of an anthropogenic influence in the heavy metals concentration through the channeled area.

scholarly journals Recent developments in nucleic acid based techniques for use in rumen manipulation

2009 ◽  
Vol 38 (spe) ◽  
pp. 341-351 ◽  
Author(s):  
Christopher McSweeney ◽  
Seungha Kang ◽  
Emma Gagen ◽  
Carl Davis ◽  
Mark Morrison ◽  
...  
Keyword(s):  
Microbial Community ◽  
Nucleic Acid ◽  
Microbial Communities ◽  
Marker Gene ◽  
Molecular Ecology ◽  
Functional Gene ◽  
Rumen Microorganisms ◽  
Dna And Rna ◽  
Conventional Culture ◽  
Reference Strains

Nucleic acid-based techniques which can be used to characterise complex microbial communities without incubation are now being employed regularly in ruminant nutrition studies. Conventional culture-based methods for enumerating rumen microorganisms (bacteria, archaea, protozoa, and fungi) have been superseded and are now used mainly to obtain pure isolates of novel organisms and reference strains that are required for the development and validation of the nucleic acid approaches. These reference strains are also essential for physiological studies of the lifestyle of the organisms as well as sources of genomic DNA and RNA that can be analysed for functional gene activity. The foundation of the molecular ecology techniques is 16S/18S rDNA sequence analysis which has provided a phylogenetically based classification scheme for enumeration and identification of microbial community members. The use of this marker gene in assays involving the use of single nucleic acid probes or primer sets is rapidly evolving to high throughput approaches such as microarray analysis and new generation sequencing technologies. While these analyses are very informative for determining the composition of the microbial community and monitoring changes in population size, they can only infer function based on these observations. The focus of nucleic acid research is now shifting to the functional analysis of the ecosystem which involves the measurement of functional genes and their expression in the predominant or specific members of the rumen microbial community. Functional gene studies are less developed than 16S rDNA-based analysis of community structure. Also for gene expression studies there are inherent problems involved in extracting high quality RNA from digesta, and priming cDNA synthesis from bacterial mRNA. This paper reviews nucleic acid based molecular methods which have recently been developed for studying the structure and function of rumen microbial communities.

scholarly journals A New Ex Vivo Model to Evaluate the Hair Protective Effect of a Biomimetic Exopolysaccharide against Water Pollution

Cosmetics ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 78
Author(s):  
Claire Tubia ◽  
Alfonso Fernández-Botello ◽  
Jan Dupont ◽  
Eni Gómez ◽  
Jérôme Desroches ◽  
...  
Keyword(s):  
Water Pollution ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Adverse Effects ◽  
Inductively Coupled Plasma ◽  
Ex Vivo ◽  
Polluted Water ◽  
Ex Vivo Model ◽  
Fiber Damage ◽  
The Impact

As an external appendage, hair is exposed to multiple stresses of different origins such as particles and gases in air, or heavy metals and chemicals in water. So far, little research has addressed the impact of water pollution on hair. The present study describes a new ex vivo model that allowed us to document the adverse effects of water pollutants on the structure of hair proteins, as well as the protective potential of active cosmetic ingredients derived from a biomimetic exopolysaccharide (EPS). The impact of water pollution was evaluated on hair from a Caucasian donor repeatedly immersed in heavy metal-containing water. Heavy metal retention in and on hair was then quantified using Inductively Coupled Plasma Spectrometry (ICP/MS). The adverse effects of heavy metals on the internal structure of hair and its prevention by the EPS were assessed through measurement of keratin birefringence. Notably, the method allows the monitoring of the organization of keratin fibers and therefore the initial change on it in order to modulate the global damage in the hair. Results revealed an increasing amount of lead, cadmium and copper, following multiple exposures to polluted water. In parallel, the structure of keratin was also altered with exposures. However, heavy metal-induced keratin fiber damage could be prevented in the presence of the tested EPS, avoiding more drastic hair problems, such as lack of shine, or decrease in strength, due to damage accumulation.

scholarly journals The influence of soil microorganisms on heavy metal content in the substrate of waste rock dumps

2021 ◽  
Vol 31 ◽  
pp. 00017
Author(s):  
Natalia Makeeva ◽  
Olga Neverova
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Content ◽  
Soil Microorganisms ◽  
Accumulation Rate ◽  
Heavy Metal Content ◽  
Waste Rock ◽  
Soil Reclamation ◽  
The Impact ◽  
Concentration Limits

The environmental effects of mining and its impact on natural resources are of a holistic nature. One of the modern methods employed for the remediation of technogenically disturbed soils is the application of microorganisms. This paper studies the impact made by soil microorganisms on the accumulation rate of heavy metals in the substrate of waste rock dumps in the process of soil reclamation. Suspensions of soil microorganisms (microorganisms utilising mineral nitrogen forms / MUMN; microorganisms decomposing silicates / MDS; microscopic fungi / MF) were applied to the rock dump surface. Separate groups as well as their combinations were applied. The heavy metal content analysis did not indicate a significant exceedance of the maximum allowable concentration limits (MACL) in the soil of the waste rock. The only metal whose content exceeded the maximum admissible concentration limits was nickel. It has found that the application of microorganisms influences the concentration of several heavy metals due to pH level changes of the rock dump soil.

scholarly journals INVESTIGATION INTO HEAVY METAL CONCENTRATION BY THE GRAVEL ROADSIDES / SUNKIŲJŲ METALŲ KONCENTRACIJŲ ŽVYRKELIŲ PAKELIŲ DIRVOŽEMIUOSE VERTINIMAS / ОЦЕНКА КОНЦЕНТР АЦИЙ ТЯЖЕЛЫХ МЕТАЛЛОВ В ПОЧВЕ ОБОЧИН ГРАВИЙНЫХ ДОРОГ

2011 ◽  
Vol 19 (1) ◽  
pp. 89-100 ◽  
Author(s):  
Audronė Mikalajunė ◽  
Lina Jakučionytė
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Concentration ◽  
Road Dust ◽  
Heavy Metal Concentration ◽  
Concentration Limit ◽  
Roadside Soils ◽  
Oil Emulsion ◽  
Gravel Roads ◽  
The Impact

Vehicles release large amounts of heavy metals to the environment. There have been done a lot of investigations analysing the distribution of heavy metals in soils near intensive regional roads. However, there is lack of investigations into the impact of small-intensity gravel roads on roadside soil contamination with heavy metals. The object of this investigation is four gravel roads of local significance connecting small villages. The intensity of these roads is very low. The gravel roads are chosen according to application of dust-minimizing materials, for example, CaCl2 and oil emulsion. According to our results, none of the soil samples had an excess of heavy metal concentration limit. Besides, heavy metal concentrations were decreasing with a distance from the road increasing. We can make an assumption that road dust-minimizing materials do not have a significant impact on heavy metal distribution in roadside soils. The major factors of heavy metal pollution distribution in roadside soils are traffic intensity, roadside trenches, and topographic conditions. Santrauka Eksploatuojant autotransportą, į aplinką patenka daug sunkiųjų metalų. Atlikta nemažai tyrimų sunkiųjų metalų paplitimuidirvožemyje šalia intensyvių magistralinių kelių nustatyti, tačiau mažo intensyvumo keliai šiuo požiūriu tiriami mažai.Tirti pasirinkta 4 žvyrkeliai – vietinės reikšmvs keliai, jungiantys nedideles gyvenvietes. Eismo intensyvumas šiuose keliuose mažas. Žvyrkeliai pasirinkti pagal taikomas priemones dulkėtumui mažinti, t. y. du nagrinvjami žvyrkeliai apdorotiCaCl2, kiti du – naftos emulsija. Nė viename mėginyje sunkiųjų metalų koncentracijos neviršijo DLK, o tolstant nuo važiuojamosios kelio dalies sunkiųjų metalų koncentracijos buvo mažesnės. Galima daryti prielaidą, kad kelio apdorojimo medžiagos dulkėtumui mažinti žymios įtakos sunkiųjų metalų pasiskirstymui pakelių dirvožemyje nedaro, lemia transporto srauto intensyvumas, kelio grioviai pakelėse bei reljefo sąlygos. Резюме При эксплуатации автомобилей в окружающую среду попадает много тяжелых металлов. Проведено немалоисследований, посвященных анализу распространения тяжелых металлов в почве обочин интенсивно эксплуатируемых магистральных дорог, однако исследований, касающихся аналогичных проблем дорог малой интенсивности, в настоящее время имеется немного. В настоящей работе в качестве объекта исследований выбраны четыредороги местного значения с гравийным покрытием, соединяющие небольшие поселения. Интенсивность дорог небольшая. Гравийные дороги выбраны с учетом их обработки для уменьшения пыльности – две дороги обработаны с применением CaCl2, а две другие – с применением нефтяной эмульсии. Ни в одной пробе не былозафиксировано концентраций тяжелых металлов, превышающих допустимые нормами. С удалением от проезжей части концентрации тяжелых металлов уменьшались. На основании исследований можно сделать вывод о том,что материалы, применявшиеся для уменьшения пыльности дорог, большого влияния на распространениетяжелых металлов в почве обочин дорог не оказывают. На распространение тяжелых металлов в почве обочин оказывает влияние интенсивность транспортного потока, кюветы на обочинах и условия рельефа.

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